1
|
Wang J, Marks JH, Batrakova EA, Tuchin SO, Antonov IO, Kaiser RI. Formation of methylglyoxal (CH 3C(O)CHO) in interstellar analog ices - a key intermediate in cellular metabolism. Phys Chem Chem Phys 2024; 26:23654-23662. [PMID: 39224052 DOI: 10.1039/d4cp02779e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Ketoaldehydes are key intermediates in biochemical processes including carbohydrate, lipid, and amino acid metabolism. Despite their crucial role in the interstellar synthesis of essential biomolecules necessary for the Origins of Life, their formation mechanisms have largely remained elusive. Here, we report the first bottom-up formation of methylglyoxal (CH3C(O)CHO)-the simplest ketoaldehyde-through the barrierless recombination of the formyl (HĊO) radical with the acetyl (CH3ĊO) radical in low-temperature interstellar ice analogs upon exposure to energetic irradiation as proxies of galactic cosmic rays. Utilizing vacuum ultraviolet photoionization reflectron time-of-flight mass spectrometry and isotopic substitution studies, methylglyoxal and its enol tautomer 2-hydroxypropenone (CH3C(OH)CO) were identified in the gas phase during the temperature-programmed desorption of irradiated carbon monoxide-acetaldehyde (CO-CH3CHO) ices, suggesting their potential as promising candidates for future astronomical searches. Once synthesized in cold molecular clouds, methylglyoxal can serve as a key precursor to sugars, sugar acids, and amino acids. Furthermore, this work provides the first experimental evidence for tautomerization of a ketoaldehyde in interstellar ice analogs, advancing our fundamental knowledge of how ketoaldehydes and their enol tautomers can be synthesized in deep space.
Collapse
Affiliation(s)
- Jia Wang
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Joshua H Marks
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | | | | | - Ivan O Antonov
- Samara National Research University, Samara 443086, Russia.
| | - Ralf I Kaiser
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| |
Collapse
|
2
|
Goettl SJ, Yang Z, He C, Somani A, Portela-Gonzalez A, Sander W, Mebel AM, Kaiser RI. Exploring the chemical dynamics of phenanthrene (C 14H 10) formation via the bimolecular gas-phase reaction of the phenylethynyl radical (C 6H 5CC) with benzene (C 6H 6). Faraday Discuss 2024; 251:509-522. [PMID: 38766758 DOI: 10.1039/d3fd00159h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
The exploration of the fundamental formation mechanisms of polycyclic aromatic hydrocarbons (PAHs) is crucial for the understanding of molecular mass growth processes leading to two- and three-dimensional carbonaceous nanostructures (nanosheets, graphenes, nanotubes, buckyballs) in extraterrestrial environments (circumstellar envelopes, planetary nebulae, molecular clouds) and combustion systems. While key studies have been conducted exploiting traditional, high-temperature mechanisms such as the hydrogen abstraction-acetylene addition (HACA) and phenyl addition-dehydrocyclization (PAC) pathways, the complexity of extreme environments highlights the necessity of investigating chemically diverse mass growth reaction mechanisms leading to PAHs. Employing the crossed molecular beams technique coupled with electronic structure calculations, we report on the gas-phase synthesis of phenanthrene (C14H10)-a three-ring, 14π benzenoid PAH-via a phenylethynyl addition-cyclization-aromatization mechanism, featuring bimolecular reactions of the phenylethynyl radical (C6H5CC, X2A1) with benzene (C6H6) under single collision conditions. The dynamics involve a phenylethynyl radical addition to benzene without entrance barrier leading eventually to phenanthrene via indirect scattering dynamics through C14H11 intermediates. The barrierless nature of reaction allows rapid access to phenanthrene in low-temperature environments such as cold molecular clouds which can reach temperatures as low as 10 K. This mechanism constitutes a unique, low-temperature framework for the formation of PAHs as building blocks in molecular mass growth processes to carbonaceous nanostructures in extraterrestrial environments thus affording critical insight into the low-temperature hydrocarbon chemistry in our universe.
Collapse
Affiliation(s)
- Shane J Goettl
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA.
| | - Zhenghai Yang
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA.
| | - Chao He
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA.
| | - Ankit Somani
- Lehrstuhl für Organische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany.
| | | | - Wolfram Sander
- Lehrstuhl für Organische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany.
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA.
| |
Collapse
|
3
|
Díaz Soto LJ, Oliveira RR, Baptista L, da Silveira EF, Nascimento MAC. Energy and spectroscopic parameters of neutral and cations isomers of the C nH 2 (n = 2-6) families using high-level ab-initio approaches. J Comput Chem 2024. [PMID: 39177429 DOI: 10.1002/jcc.27485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 07/27/2024] [Accepted: 08/02/2024] [Indexed: 08/24/2024]
Abstract
Cationic species, previously detected from ion-induced desorption of solid methane by plasma desorption mass spectrometry (PDMS), and neutral species, are investigated using high-level ab-initio approaches. From a set of 25 cationic and 26 neutral structures belonging to CnH2 (n = 2-6) families, it was obtained the energy, rotational constants, harmonic vibrational frequency, charge distribution and excitation energies. The ZPVE-corrected energies, at CCSD(T)-F12; CCSD(T)-F12/RI/(cc-pVTZ-F12, cc-pVTZ-F12-CABS, cc-pVQZ/C) (n = 2-5) and CCSD(T)/cc-pVTZ (n = 6) levels, reveal that the topology of the most stable isomer vary with n and the charge. Out of 674 harmonic frequencies, those with maximum intensity are generally in the 3000-3500 cm-1 range. Analysis of 169 vertical transition energies calculated with the EOM-CCSD approach, suggest three C6H2 species as potential carriers of the diffuse interstellar bands (DIB). Systematic comparison of properties between neutral and cationic species can assist in the structural description of complex matrices.
Collapse
Affiliation(s)
- Lenin J Díaz Soto
- Instituto de Química, Universidade Federal do Rio de Janeiro, Cidade Universitária, CT, Rio de Janeiro, Brazil
| | - Ricardo R Oliveira
- Instituto de Química, Universidade Federal do Rio de Janeiro, Cidade Universitária, CT, Rio de Janeiro, Brazil
| | - Leonardo Baptista
- Departamento de Química e Ambiental, Faculdade de Tecnologia, Universidade do Estado do Rio de Janeiro, Resende, Brazil
| | - Enio F da Silveira
- Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, Rio de Janeiro, Brazil
| | | |
Collapse
|
4
|
Chen X, Li Y, Xie M, Hu Y. Growth mechanism of aromatic prebiotic molecules: insights from different processes of ion-molecule reactions in benzonitrile-ammonia and benzonitrile-methylamine clusters. Phys Chem Chem Phys 2024; 26:21548-21557. [PMID: 39082110 DOI: 10.1039/d4cp01603c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
Benzonitrile (BN, C6H5CN) has been detected in the cold molecular cloud Taurus molecular cloud-1 (TMC-1) in 2018, which is suggested to be a precursor in the formation of more complex nitrogen-containing aromatic interstellar compounds. In this study, we utilized mass-selected infrared (IR) photodissociation spectroscopy and quantum chemical calculations to investigate the structures and gaseous ion-molecule reactions of benzonitrile-ammonia (BN-NH3) and benzonitrile-methylamine (BN-MA) clusters. The spectral observations indicate that the cyclic hydrogen bonding structure predominates in both neutral clusters. After VUV (118 nm) single-photon ionization, a new C-N covalent bond formed between BN and NH3 in the (BN-NH3)+ cluster. However, proton sharing constitutes the primary structure of the (BN-MA)+ cluster. The two nitrogen-containing interstellar molecules react with BN to yield distinct products due to difference in charge distribution and molecular polarity in the ionized clusters. The reactions of BN with other molecules contribute to our understanding of the growth mechanisms of complex interstellar molecules.
Collapse
Affiliation(s)
- Xutao Chen
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
| | - Yujian Li
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
| | - Min Xie
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
| | - Yongjun Hu
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
| |
Collapse
|
5
|
Goettl SJ, He C, Yang Z, Kaiser RI, Somani A, Portela-Gonzalez A, Sander W, Sun BJ, Fatimah S, Kadam KP, Chang AHH. Unconventional gas-phase synthesis of biphenyl and its atropisomeric methyl-substituted derivatives. Phys Chem Chem Phys 2024; 26:18321-18332. [PMID: 38912536 DOI: 10.1039/d4cp00765d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
The biphenyl molecule (C12H10) acts as a fundamental molecular backbone in the stereoselective synthesis of organic materials due to its inherent twist angle causing atropisomerism in substituted derivatives and in molecular mass growth processes in circumstellar environments and combustion systems. Here, we reveal an unconventional low-temperature phenylethynyl addition-cyclization-aromatization mechanism for the gas-phase preparation of biphenyl (C12H10) along with ortho-, meta-, and para-substituted methylbiphenyl (C13H12) derivatives through crossed molecular beams and computational studies providing compelling evidence on their formation via bimolecular gas-phase reactions of phenylethynyl radicals (C6H5CC, X2A1) with 1,3-butadiene-d6 (C4D6), isoprene (CH2C(CH3)CHCH2), and 1,3-pentadiene (CH2CHCHCHCH3). The dynamics involve de-facto barrierless phenylethynyl radical additions via submerged barriers followed by facile cyclization and hydrogen shift prior to hydrogen atom emission and aromatization to racemic mixtures (ortho, meta) of biphenyls in overall exoergic reactions. These findings not only challenge our current perception of biphenyls as high temperature markers in combustion systems and astrophysical environments, but also identify biphenyls as fundamental building blocks of complex polycyclic aromatic hydrocarbons (PAHs) such as coronene (C24H12) eventually leading to carbonaceous nanoparticles (soot, grains) in combustion systems and in deep space thus affording critical insight into the low-temperature hydrocarbon chemistry in our universe.
Collapse
Affiliation(s)
- Shane J Goettl
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Chao He
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Ankit Somani
- Lehrstuhl für Organische Chemie II, Ruhr-Universität Bochum, Bochum 44801, Germany.
| | | | - Wolfram Sander
- Lehrstuhl für Organische Chemie II, Ruhr-Universität Bochum, Bochum 44801, Germany.
| | - Bing-Jian Sun
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan.
| | - Siti Fatimah
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan.
| | - Komal P Kadam
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan.
| | - Agnes H H Chang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan.
| |
Collapse
|
6
|
McAnally M, Bocková J, Herath A, Turner AM, Meinert C, Kaiser RI. Abiotic formation of alkylsulfonic acids in interstellar analog ices and implications for their detection on Ryugu. Nat Commun 2024; 15:4409. [PMID: 38782930 DOI: 10.1038/s41467-024-48684-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
For the last century, the source of sulfur in Earth's very first organisms has remained a fundamental, unsolved enigma. While sulfates and their organic derivatives with sulfur in the S(+VI) oxidation state represent core nutrients in contemporary biochemistry, the limited bioavailability of sulfates during Earth's early Archean period proposed that more soluble S(+IV) compounds served as the initial source of sulfur for the first terrestrial microorganisms. Here, we reveal via laboratory simulation experiments that the three simplest alkylsulfonic acids-water soluble organic S(+IV) compounds-can be efficiently produced in interstellar, sulfur-doped ices through interaction with galactic cosmic rays. This discovery opens a previously elusive path into the synthesis of vital astrobiological significance and untangles fundamental mechanisms of a facile preparation of sulfur-containing, biorelevant organics in extraterrestrial ices; these molecules can be eventually incorporated into comets and asteroids before their delivery and detection on Earth such as in the Murchison, Tagish Lake, and Allende meteorites along with the carbonaceous asteroid Ryugu.
Collapse
Affiliation(s)
- Mason McAnally
- Department of Chemistry, University of Hawaii at Mānoa, Honolulu, HI, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Mānoa, Honolulu, HI, USA
| | - Jana Bocková
- Université Côte d'Azur, Institut de Chimie de Nice, UMR 7272 CNRS, Nice, France
| | - Ashanie Herath
- Department of Chemistry, University of Hawaii at Mānoa, Honolulu, HI, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Mānoa, Honolulu, HI, USA
| | - Andrew M Turner
- Department of Chemistry, University of Hawaii at Mānoa, Honolulu, HI, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Mānoa, Honolulu, HI, USA
| | - Cornelia Meinert
- Université Côte d'Azur, Institut de Chimie de Nice, UMR 7272 CNRS, Nice, France.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawaii at Mānoa, Honolulu, HI, USA.
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Mānoa, Honolulu, HI, USA.
| |
Collapse
|
7
|
Krischer F, Swamy VSVSN, Feichtner KS, Ward RJ, Gessner VH. The Cyanoketenyl Anion [NC 3O] . Angew Chem Int Ed Engl 2024; 63:e202403766. [PMID: 38470943 DOI: 10.1002/anie.202403766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/05/2024] [Accepted: 03/08/2024] [Indexed: 03/14/2024]
Abstract
Cumulenes and heterocumulenes with three or more cumulative multiple bonds are usually reactive species that serve as valuable building blocks for more complex molecules but tend to isomerize or cyclize and therefore are difficult to isolate. Using a mild ligand exchange reaction at the carbon in α-metalated ylides, we have now succeeded in the synthesis and gram-scale isolation of the elusive cyanoketenyl anion [NC3O]-. Despite its assumed cumulene-like structure and the delocalization of the negative charge across the whole 5-atom molecule, it features a bent geometry with a nucleophilic central carbon atom. Computational studies reveal an ambiguous bonding situation in the anion, which can be illustrated only by a combination of different resonance structures. Nonetheless, the anion features remarkable stability, thus allowing the storage of its potassium-crown ether salt and its application as a highly functional synthetic building block. The cyanoketenyl anion readily reacts with a series of small molecules to form more complex organic compounds, including industrially valuable compounds such as cyanoacetate. This work demonstrated that reactive species can be generated by novel synthesis methods and open up atom-economic pathways to complex compounds from small abundant molecules.
Collapse
Affiliation(s)
- Felix Krischer
- Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Varre S V S N Swamy
- Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Kai-Stephan Feichtner
- Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Robert J Ward
- Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Viktoria H Gessner
- Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| |
Collapse
|
8
|
Nixon CA. The Composition and Chemistry of Titan's Atmosphere. ACS EARTH & SPACE CHEMISTRY 2024; 8:406-456. [PMID: 38533193 PMCID: PMC10961852 DOI: 10.1021/acsearthspacechem.2c00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 11/02/2023] [Accepted: 02/02/2024] [Indexed: 03/28/2024]
Abstract
In this review I summarize the current state of knowledge about the composition of Titan's atmosphere and our current understanding of the suggested chemistry that leads to that observed composition. I begin with our present knowledge of the atmospheric composition, garnered from a variety of measurements including Cassini-Huygens, the Atacama Large Millimeter/submillimeter Array, and other ground- and space-based telescopes. This review focuses on the typical vertical profiles of gases at low latitudes rather than global and temporal variations. The main body of the review presents a chemical description of how complex molecules are believed to arise from simpler species, considering all known "stable" molecules-those that have been uniquely identified in the neutral atmosphere. The last section of the review is devoted to the gaps in our present knowledge of Titan's chemical composition and how further work may fill those gaps.
Collapse
Affiliation(s)
- Conor A. Nixon
- Planetary Systems Laboratory, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, Maryland 20771, United
States
| |
Collapse
|
9
|
Medvedkov IA, Nikolayev AA, Yang Z, Goettl SJ, Mebel AM, Kaiser RI. Elucidating the chemical dynamics of the elementary reactions of the 1-propynyl radical (CH 3CC; X 2A 1) with 2-methylpropene ((CH 3) 2CCH 2; X 1A 1). Phys Chem Chem Phys 2024; 26:6448-6457. [PMID: 38319693 DOI: 10.1039/d3cp05872g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Exploiting the crossed molecular beam technique, we studied the reaction of the 1-propynyl radical (CH3CC; X2A1) with 2-methylpropene (isobutylene; (CH3)2CCH2; X1A1) at a collision energy of 38 ± 3 kJ mol-1. The experimental results along with ab initio and statistical calculations revealed that the reaction has no entrance barrier and proceeds via indirect scattering dynamics involving C7H11 intermediates with lifetimes longer than their rotation period(s). The reaction is initiated by the addition of the 1-propynyl radical with its radical center to the π-electron density at the C1 and/or C2 position in 2-methylpropene. Further, the C7H11 intermediate formed from the C1 addition either emits atomic hydrogen or undergoes isomerization via [1,2-H] shift from the CH3 or CH2 group prior to atomic hydrogen loss preferentially leading to 1,2,4-trimethylvinylacetylene (2-methylhex-2-en-4-yne) as the dominant product. The molecular structures of the collisional complexes promote hydrogen atom loss channels. RRKM results show that hydrogen elimination channels dominate in this reaction, with a branching ratio exceeding 70%. Since the reaction of the 1-propynyl radical with 2-methylpropene has no entrance barrier, is exoergic, and all transition states involved are located below the energy of the separated reactants, bimolecular collisions are feasible to form trimethylsubstituted 1,3-enyne (p1) via a single collision event even at temperatures as low as 10 K prevailing in cold molecular clouds such as G+0.693. The formation of trimethylsubstituted vinylacetylene could serve as the starting point of fundamental molecular mass growth processes leading to di- and trimethylsubstituted naphthalenes via the HAVA mechanism.
Collapse
Affiliation(s)
- Iakov A Medvedkov
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA.
| | | | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA.
| | - Shane J Goettl
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA.
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA.
| |
Collapse
|
10
|
Marks J, Wang J, Sun BJ, McAnally M, Turner AM, Chang AHH, Kaiser RI. Thermal Synthesis of Carbamic Acid and Its Dimer in Interstellar Ices: A Reservoir of Interstellar Amino Acids. ACS CENTRAL SCIENCE 2023; 9:2241-2250. [PMID: 38161363 PMCID: PMC10755733 DOI: 10.1021/acscentsci.3c01108] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 01/03/2024]
Abstract
Reactions in interstellar ices are shown to be capable of producing key prebiotic molecules without energetic radiation that are necessary for the origins of life. When present in interstellar ices, carbamic acid (H2NCOOH) can serve as a condensed-phase source of the molecular building blocks for more complex proteinogenic amino acids. Here, Fourier transform infrared spectroscopy during heating of analogue interstellar ices composed of carbon dioxide and ammonia identifies the lower limit for thermal synthesis to be 62 ± 3 K for carbamic acid and 39 ± 4 K for its salt ammonium carbamate ([H2NCOO-][NH4+]). While solvation increases the rates of formation and decomposition of carbamic acid in ice, the absence of solvent effects after sublimation results in a significant barrier to dissociation and a stable gas-phase molecule. Photoionization reflectron time-of-flight mass spectrometry permits an unprecedented degree of sensitivity toward gaseous carbamic acid and demonstrates sublimation of carbamic acid from decomposition of ammonium carbamate and again at higher temperatures from carbamic acid dimers. Since the dimer is observed at temperatures up to 290 K, similar to the environment of a protoplanetary disk, this dimer is a promising reservoir of amino acids during the formation of stars and planets.
Collapse
Affiliation(s)
- Joshua
H. Marks
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Jia Wang
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Bing-Jian Sun
- Department
of Chemistry, National Dong Hwa University, Hualien 974, Taiwan
| | - Mason McAnally
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Andrew M. Turner
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| | - Agnes H.-H. Chang
- Department
of Chemistry, National Dong Hwa University, Hualien 974, Taiwan
| | - Ralf I. Kaiser
- W.
M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
- Department
of Chemistry, University of Hawai’i
at Manoa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
11
|
Kaiser RI. Unraveling the complex inventory of biorelevant organics in the plumes of icy moons. Proc Natl Acad Sci U S A 2023; 120:e2319167120. [PMID: 38109557 PMCID: PMC10756203 DOI: 10.1073/pnas.2319167120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2023] Open
Affiliation(s)
- Ralf I. Kaiser
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, HI96822
- Department of Chemistry, University of Hawai’i at Manoa, Honolulu, HI96822
| |
Collapse
|
12
|
Medvedkov IA, Nikolayev AA, He C, Yang Z, Mebel AM, Kaiser RI. One Collision-Two Substituents: Gas-Phase Preparation of Xylenes under Single-Collision Conditions. Angew Chem Int Ed Engl 2023:e202315147. [PMID: 38072833 DOI: 10.1002/anie.202315147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Indexed: 12/21/2023]
Abstract
The fundamental reaction pathways to the simplest dialkylsubstituted aromatics-xylenes (C6 H4 (CH3 )2 )-in high-temperature combustion flames and in low-temperature extraterrestrial environments are still unknown, but critical to understand the chemistry and molecular mass growth processes in these extreme environments. Exploiting crossed molecular beam experiments augmented by state-of-the-art electronic structure and statistical calculations, this study uncovers a previously elusive, facile gas-phase synthesis of xylenes through an isomer-selective reaction of 1-propynyl (methylethynyl, CH3 CC) with 2-methyl-1,3-butadiene (isoprene, C5 H8 ). The reaction dynamics are driven by a barrierless addition of the radical to the diene moiety of 2-methyl-1,3-butadiene followed by extensive isomerization (hydrogen shifts, cyclization) prior to unimolecular decomposition accompanied by aromatization via atomic hydrogen loss. This overall exoergic reaction affords a preparation of xylenes not only in high-temperature environments such as in combustion flames and around circumstellar envelopes of carbon-rich Asymptotic Giant Branch (AGB) stars, but also in low-temperature cold molecular clouds (10 K) and in hydrocarbon-rich atmospheres of planets and their moons such as Triton and Titan. Our study established a hitherto unknown gas-phase route to xylenes and potentially more complex, disubstituted benzenes via a single collision event highlighting the significance of an alkyl-substituted ethynyl-mediated preparation of aromatic molecules in our Universe.
Collapse
Affiliation(s)
- Iakov A Medvedkov
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA
| | | | - Chao He
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA
| | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA
| |
Collapse
|
13
|
Pharr CR, Esselman BJ, McMahon RJ. Photochemistry of 1-(2- and 3-Thienyl)diazoethanes: Spectroscopy and Tunneling Reaction of Triplet 1-(3-Thienyl)ethylidene. J Org Chem 2023; 88:16176-16185. [PMID: 37948641 DOI: 10.1021/acs.joc.3c01639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Photolysis (λ > 613 nm) of 1-(3-thienyl)diazoethane (21) yields the s-E rotamer of triplet 1-(3-thienyl)ethylidene (3), as characterized by UV/vis and EPR spectroscopy. The s-Z rotamer of 3 was not observed. EPR and UV/vis signals attributed to carbene 3 decrease by approximately 50% upon standing in the dark for 68 h at 10 K. Although formally spin-forbidden, an intramolecular [1,2]-hydrogen shift in triplet carbene 3 to afford singlet s-E 3-vinylthiophene (8) is presumed to occur via quantum mechanical tunneling. The behavior of the CD3 analogue supports this interpretation. Photolysis (λ > 613 nm) of 1-(3-thienyl)diazoethane-d3 (21-d3) yields triplet 1-(3-thienyl)ethylidene-d3 (3-d3), as characterized by IR, UV/vis, and EPR spectroscopy. No change in the signal intensity of EPR and UV/vis signals of triplet 3-d3 is observed upon standing in the dark for 68 h at 10 K. In a series of 2-substituted thienyl derivatives, irradiation of 1-(2-thienyl)diazoethane (22), 1-(2-thienyl)diazoethane-d3 (22-d3), or (3-methyl-2-thienyl)diazomethane (23) does not yield triplet carbene intermediates. Positioning and labeling of the methyl group proved to have a large effect on products observed for these species. 1-(2-Thienyl)diazoethane (22) yields the products of [1,2]-hydrogen migration, s-Z and s-E 2-vinylthiophene (7), while 22-d3 and 23 give products derived from opening of the thiophene ring.
Collapse
Affiliation(s)
- Caroline R Pharr
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - Brian J Esselman
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - Robert J McMahon
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| |
Collapse
|
14
|
Yang Z, Galimova GR, He C, Goettl SJ, Paul D, Lu W, Ahmed M, Mebel AM, Li X, Kaiser RI. Gas-phase formation of the resonantly stabilized 1-indenyl (C 9H 7•) radical in the interstellar medium. SCIENCE ADVANCES 2023; 9:eadi5060. [PMID: 37682989 PMCID: PMC10491290 DOI: 10.1126/sciadv.adi5060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 08/07/2023] [Indexed: 09/10/2023]
Abstract
The 1-indenyl (C9H7•) radical, a prototype aromatic and resonantly stabilized free radical carrying a six- and a five-membered ring, has emerged as a fundamental molecular building block of nonplanar polycyclic aromatic hydrocarbons (PAHs) and carbonaceous nanostructures in deep space and combustion systems. However, the underlying formation mechanisms have remained elusive. Here, we reveal an unconventional low-temperature gas-phase formation of 1-indenyl via barrierless ring annulation involving reactions of atomic carbon [C(3P)] with styrene (C6H5C2H3) and propargyl (C3H3•) with phenyl (C6H5•). Macroscopic environments like molecular clouds act as natural low-temperature laboratories, where rapid molecular mass growth to 1-indenyl and subsequently complex PAHs involving vinyl side-chained aromatics and aryl radicals can occur. These reactions may account for the formation of PAHs and their derivatives in the interstellar medium and carbonaceous chondrites and could close the gap of timescales of their production and destruction in our carbonaceous universe.
Collapse
Affiliation(s)
- Zhenghai Yang
- Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI 96822, USA
| | - Galiya R. Galimova
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Chao He
- Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI 96822, USA
| | - Shane J. Goettl
- Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI 96822, USA
| | - Dababrata Paul
- Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI 96822, USA
| | - Wenchao Lu
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Musahid Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Alexander M. Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Xiaohu Li
- Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, P. R. China
- Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, P. R. China
| | - Ralf I. Kaiser
- Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI 96822, USA
| |
Collapse
|
15
|
Turner AM, Marks JH, Luo Y, Lechner JT, Klapötke TM, Sun R, Kaiser RI. Electron-Induced Decomposition of Solid 1,1-Diamino-2,2-dinitroethylene (FOX-7) at Cryogenic Temperatures. J Phys Chem A 2023; 127:3390-3401. [PMID: 37027514 DOI: 10.1021/acs.jpca.3c01035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
Abstract
Solid FOX-7 (1,1-diamino-2,2-dinitroethylene), an energetic material of interest due to its high stability and low shock/thermal sensitivity, was exposed to energetic electrons at 5 K to explore the fundamental mechanisms leading to decomposition products and provide a better understanding of the reaction pathways involved. As a result of the radiation exposure, infrared spectroscopy revealed carbon dioxide (CO2) and carbon monoxide (CO) trapped in the FOX-7 matrix, while these compounds along with water (H2O), nitrogen monoxide (NO), and cyanogen (C2N2) were detected exploiting quadrupole mass spectrometry both during irradiation and during the warming phase from 5 to 300 K. Photoionization reflectron time-of-flight mass spectrometry detected small molecules such as ammonia (NH3), nitrogen monoxide (NO), and nitrogen dioxide (NO2) as well as more complex molecules up to 96 amu. Potential reaction pathways are presented and assignments are discussed. Among the reaction mechanisms, the importance of an initial nitro-to-nitrite isomerization is highlighted by the observed decomposition products.
Collapse
Affiliation(s)
- Andrew M Turner
- Department of Chemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
| | - Joshua H Marks
- Department of Chemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
| | - Yuheng Luo
- Department of Chemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
| | - Jasmin T Lechner
- Department of Chemistry, Ludwig-Maximilian University of Munich, München 81377, Germany
| | - Thomas M Klapötke
- Department of Chemistry, Ludwig-Maximilian University of Munich, München 81377, Germany
| | - Rui Sun
- Department of Chemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii, Honolulu, Hawaii 96822, United States
| |
Collapse
|
16
|
West NA, Li LHD, Millar TJ, Van de Sande M, Rutter E, Blitz MA, Lehman JH, Decin L, Heard DE. Experimental and theoretical study of the low-temperature kinetics of the reaction of CN with CH 2O and implications for interstellar environments. Phys Chem Chem Phys 2023; 25:7719-7733. [PMID: 36876874 PMCID: PMC10015628 DOI: 10.1039/d2cp05043a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 02/23/2023] [Indexed: 03/07/2023]
Abstract
Rate coefficients for the reaction of CN with CH2O were measured for the first time below room temperature in the range 32-103 K using a pulsed Laval nozzle apparatus together with the Pulsed Laser Photolysis-Laser-Induced Fluorescence technique. The rate coefficients exhibited a strong negative temperature dependence, reaching (4.62 ± 0.84) × 10-11 cm3 molecule-1 s-1 at 32 K, and no pressure dependence was observed at 70 K. The potential energy surface (PES) of the CN + CH2O reaction was calculated at the CCSD(T)/aug-cc-pVTZ//M06-2X/aug-cc-pVTZ level of theory, with the lowest energy channel to reaction characterized by the formation of a weakly-bound van der Waals complex, bound by 13.3 kJ mol-1, prior to two transition states with energies of -0.62 and 3.97 kJ mol-1, leading to the products HCN + HCO or HNC + HCO, respectively. For the formation of formyl cyanide, HCOCN, a large activation barrier of 32.9 kJ mol-1 was calculated. Reaction rate theory calculations were performed with the MESMER (Master Equation Solver for Multi Energy well Reactions) package on this PES to calculate rate coefficients. While this ab initio description provided good agreement with the low-temperature rate coefficients, it was not capable of describing the high-temperature experimental rate coefficients from the literature. However, increasing the energies and imaginary frequencies of both transition states allowed MESMER simulations of the rate coefficients to be in good agreement with data spanning 32-769 K. The mechanism for the reaction is the formation of a weakly-bound complex followed by quantum mechanical tunnelling through the small barrier to form HCN + HCO products. MESMER calculations showed that channel generating HNC is not important. MESMER simulated the rate coefficients from 4-1000 K which were used to recommend best-fit modified Arrhenius expressions for use in astrochemical modelling. The UMIST Rate12 (UDfa) model yielded no significant changes in the abundances of HCN, HNC, and HCO for a variety of environments upon inclusion of rate coefficients reported here. The main implication from this study is that the title reaction is not a primary formation route to the interstellar molecule formyl cyanide, HCOCN, as currently implemented in the KIDA astrochemical model.
Collapse
Affiliation(s)
- Niclas A West
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | | | - Tom J Millar
- Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, University Road, Belfast BT7 1NN, UK
| | - Marie Van de Sande
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Edward Rutter
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | - Mark A Blitz
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | - Julia H Lehman
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| | - Leen Decin
- Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
| | - Dwayne E Heard
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
17
|
Paul D, Sun BJ, He C, Yang Z, Goettl SJ, Yang T, Zhang BY, Chang AHH, Kaiser RI. Competing Si 2CH 4-H 2 and SiCH 2-SiH 4 Channels in the Bimolecular Reaction of Ground-State Atomic Carbon (C( 3P j)) with Disilane (Si 2H 6, X 1A 1g) under Single Collision Conditions. J Phys Chem A 2023; 127:1901-1908. [PMID: 36790335 DOI: 10.1021/acs.jpca.2c08417] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The bimolecular gas-phase reaction of ground-state atomic carbon (C(3Pj)) with disilane (Si2H6, X1A1g) was explored under single-collision conditions in a crossed molecular beam machine at a collision energy of 36.6 ± 4.5 kJ mol-1. Two channels were observed: a molecular hydrogen elimination plus Si2CH4 (reaction 1) pathway and a silane loss channel along with the formation of SiCH2 (reaction 2), with branching ratios of 20 ± 3 and 80 ± 4%, respectively. Both channels involved indirect scattering dynamics via long-lived Si2CH6 reaction intermediate(s); the latter eject molecular hydrogen and silane in "molecular" elimination channels within the rotational plane of the fragmenting intermediate nearly perpendicularly to the total angular momentum vector. These molecular elimination channels are associated with tight exit transition states as reflected in a significant electron rearrangement as visible from the chemical bonding in the light reaction products molecular hydrogen and silane. Once these hydrogenated silicon-carbide clusters are formed within the inner envelope of carbon stars such as of IRC + 10216, the stellar wind can drive both Si2CH4 and SiCH2 to the outside sections of the envelope, where they can be photolyzed. This is of particular importance to unravel potential formation pathways to disilicon monocarbide (Si2C) observed recently in the circumstellar shell of IRC + 10216.
Collapse
Affiliation(s)
- Dababrata Paul
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Bing-Jian Sun
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan
| | - Chao He
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Shane J Goettl
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Tao Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Bo-Yu Zhang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan
| | - Agnes H H Chang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
18
|
Chauhan D, Limbachiya C. Electron interactions with analogous of DNA/RNA nucleobases: 3-hydroxytetrahydroFuran and α-Tetrahydrofurfuryl alcohol. Radiat Phys Chem Oxf Engl 1993 2023. [DOI: 10.1016/j.radphyschem.2023.110802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
19
|
Yang Z, Sun BJ, He C, Li JQ, Chang AHH, Kaiser RI. Gas-Phase Preparation of 1-Germavinylidene (H 2CGe; X 1A 1), the Isovalent Counterpart of Vinylidene (H 2CC; X 1A 1), via Non-adiabatic Dynamics through the Elementary Reaction of Ground State Atomic Carbon (C; 3P) with Germane (GeH 4; X 1A 1). J Phys Chem Lett 2023; 14:430-436. [PMID: 36622768 DOI: 10.1021/acs.jpclett.2c03749] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
1-Germavinylidene (H2CGe; X1A1), the germanium analogue of vinylidene (H2CC; X1A1), was prepared via a directed gas-phase synthesis through the bimolecular reaction of ground state atomic carbon (C; 3P) with germane (GeH4; X1A1) under single-collision conditions. The reaction commences with the barrierless insertion of carbon into the Ge-H bond followed by intersystem crossing from the triplet to singlet surface and migration of atomic hydrogen to germylene (H2GeCH2), which predominantly decomposes via molecular hydrogen loss to 1-germavinylidene (H2CGe; X1A1). Therefore, the replacement of a single carbon atom in the acetylene-vinylidene system by germanium critically impacts the chemical bonding, molecular structure, and thermodynamic stability of the carbene-type structures favoring 1-germavinylidene (H2CGe) over germyne (HGeCH) by 160 kJ mol-1. Hence, the carbon-germane system represents a benchmark in the exploration of the chemistries of main group 14 elements with germanium-bearing systems showing few similarities with the isovalent carbon system.
Collapse
Affiliation(s)
- Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Bing-Jian Sun
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan
| | - Chao He
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Jin-Qi Li
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan
| | - Agnes H H Chang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
20
|
Wang J, Marks JH, Turner AM, Nikolayev AA, Azyazov V, Mebel AM, Kaiser RI. Mechanistical study on the formation of hydroxyacetone (CH 3COCH 2OH), methyl acetate (CH 3COOCH 3), and 3-hydroxypropanal (HCOCH 2CH 2OH) along with their enol tautomers (prop-1-ene-1,2-diol (CH 3C(OH)CHOH), prop-2-ene-1,2-diol (CH 2C(OH)CH 2OH), 1-methoxyethen-1-ol (CH 3OC(OH)CH 2) and prop-1-ene-1,3-diol (HOCH 2CHCHOH)) in interstellar ice analogs. Phys Chem Chem Phys 2023; 25:936-953. [PMID: 36285574 DOI: 10.1039/d2cp03543j] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We unravel, for the very first time, the formation pathways of hydroxyacetone (CH3COCH2OH), methyl acetate (CH3COOCH3), and 3-hydroxypropanal (HCOCH2CH2OH), as well as their enol tautomers within mixed ices of methanol (CH3OH) and acetaldehyde (CH3CHO) analogous to interstellar ices in the ISM exposed to ionizing radiation at ultralow temperatures of 5 K. Exploiting photoionization reflectron time-of-flight mass spectrometry (PI-ReToF-MS) and isotopically labeled ices, the reaction products were selectively photoionized allowing for isomer discrimination during the temperature-programmed desorption phase. Based on the distinct mass-to-charge ratios and ionization energies of the identified species, we reveal the formation pathways of hydroxyacetone (CH3COCH2OH), methyl acetate (CH3COOCH3), and 3-hydroxypropanal (HCOCH2CH2OH) via radical-radical recombination reactions and of their enol tautomers (prop-1-ene-1,2-diol (CH3C(OH)CHOH), prop-2-ene-1,2-diol (CH2C(OH)CH2OH), 1-methoxyethen-1-ol (CH3OC(OH)CH2) and prop-1-ene-1,3-diol (HOCH2CHCHOH)) via keto-enol tautomerization. To the best of our knowledge, 1-methoxyethen-1-ol (CH3OC(OH)CH2) and prop-1-ene-1,3-diol (HOCH2CHCHOH) are experimentally identified for the first time. Our findings help to constrain the formation mechanism of hydroxyacetone and methyl acetate detected within star-forming regions and suggest that the hitherto astronomically unobserved isomer 3-hydroxypropanal and its enol tautomers represent promising candidates for future astronomical searches. These enol tautomers may contribute to the molecular synthesis of biologically relevant molecules in deep space due to their nucleophilic character and high reactivity.
Collapse
Affiliation(s)
- Jia Wang
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA. .,Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Joshua H Marks
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA. .,Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Andrew M Turner
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA. .,Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Anatoliy A Nikolayev
- Lebedev Physical Institute, Samara 443011, Russia.,Samara National Research University, Samara 443086, Russia
| | | | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, USA
| | - Ralf I Kaiser
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA. .,Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| |
Collapse
|
21
|
Yang Z, Doddipatla S, He C, Goettl SJ, Kaiser RI, Jasper AW, Gomes ACR, Galvão BRL. Can third-body stabilisation of bimolecular collision complexes in cold molecular clouds happen? Mol Phys 2022. [DOI: 10.1080/00268976.2022.2134832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Zhenghai Yang
- Department of Chemistry, University of Hawai’i at Manoa, Honolulu, HI, USA
| | | | - Chao He
- Department of Chemistry, University of Hawai’i at Manoa, Honolulu, HI, USA
| | - Shane J. Goettl
- Department of Chemistry, University of Hawai’i at Manoa, Honolulu, HI, USA
| | - Ralf I. Kaiser
- Department of Chemistry, University of Hawai’i at Manoa, Honolulu, HI, USA
| | - Ahren W. Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA
| | - Alexandre C. R. Gomes
- Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Minas Gerais, Brazil
| | - Breno R. L. Galvão
- Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Minas Gerais, Brazil
| |
Collapse
|
22
|
Galimova GR, Mebel AM, Goettl SJ, Yang Z, Kaiser RI. A crossed molecular beams and computational study on the unusual reactivity of banana bonds of cyclopropane (c-C 3H 6; ) through insertion by ground state carbon atoms (C( 3P j)). Phys Chem Chem Phys 2022; 24:22453-22463. [PMID: 36102937 DOI: 10.1039/d2cp03293g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The mechanism and chemical dynamics of the reaction of ground electronic state atomic carbon C(3Pj) with cyclopropane c-C3H6 have been explored by combining crossed molecular beams experiments with electronic structure calculations of the pertinent triplet C4H6 potential energy surface and statistical computations of product branching ratios under single-collision conditions. The experimental findings suggest that the reaction proceeds via indirect scattering dynamics through triplet C4H6 reaction intermediate(s) leading to C4H5 product(s) plus atomic hydrogen via a tight exit transition state, with the overall reaction exoergicity evaluated as 231 ± 52 kJ mol-1. The calculations indicate that C(3Pj) can easily insert into one of the three equivalent C-C 'banana' bonds of cyclopropane overcoming a low barrier of only 2 kJ mol-1 following the formation of a van der Waals reactant complex stabilized by 15 kJ mol-1. The carbon atom insertion into one of the six C-H bonds is also feasible via a slightly higher barrier of 5 kJ mol-1. These results highlight an unusual reactivity of cyclopropane's banana C-C bonds, which behave more like unsaturated C-C bonds with a π-character than saturated σ C-C bonds, which are known to be generally unreactive toward the ground electronic state atomic carbon such as in ethane (C2H6). The statistical theory predicts the overall product branching ratios at the experimental collision energy as 50% for 1-butyn-4-yl, 33% for 1,3-butadien-2-yl, i-C4H5, and 11% for 1,3-butadien-1-yl, n-C4H5, with i-C4H5 (230 kJ mol-1 below the reactants) favored by the C-C insertion providing the best match with the experimentally observed reaction exoergicity. The C(3Pj) + c-C3H6 reaction is predicted to be a source of C4H5 radicals under the conditions where its low entrance barriers can be overcome, such as in planetary atmospheres or in circumstellar envelopes but not in cold molecular clouds. Both i- and n-C4H5 can further react with acetylene eventually producing the first aromatic ring and hence, the reaction of the atomic carbon with c-C3H6 can be considered as an initial step toward the formation of benzene.
Collapse
Affiliation(s)
- Galiya R Galimova
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.
| | - Shane J Goettl
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
| |
Collapse
|
23
|
Roy T, Thimmakondu VS, Ghosal S. New Carbenes and Cyclic Allenes Energetically Comparable to Experimentally Known 1-Azulenylcarbene. ACS OMEGA 2022; 7:30149-30160. [PMID: 36061723 PMCID: PMC9435053 DOI: 10.1021/acsomega.2c03224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
1-Azulenylcarbene (18; 0 kJ mol-1) is experimentally known as the key reactive intermediate for the rearrangement reactions of aryl carbenes in the laboratory. Here, using coupled-cluster methods up to the fc-CCSD(T)/cc-pVTZ//fc-CCSD(T)/cc-pVDZ level, thirteen new carbenes and one new cyclic allene are theoretically identified within the C11H8 elemental composition that either energetically lie below or very close to 18. While the cyclic allene, bicyclo[5.4.0]undeca-2,3,5,7,9,11-hexene (1; -166 kJ mol-1), is the experimentally known lowest energy isomer, three other cyclic allenes, bicyclo[5.4.0]undeca-1,2,4,6,8,10-hexene (2; -100 kJ mol-1), bicyclo[5.4.0]undeca-1,3,4,6,8,10-hexene (3; -97 kJ mol-1), and bicyclo[6.3.0]undeca-1,2,4,6,8,10-hexene (13; -42 kJ mol-1), demand new experimental studies. In total, thirty-one isomers are studied in this work (within -166 to +15 kJ mol-1 from 18) and all are found to be polar (μ ≠ 0). Among these, 1H-benzo[7]annulen-1-ylidene (17; -4 kJ mol-1; μ = 5.24 D), bicyclo[5.4.0]undeca-2,4,6,8,11-pentaene-10-ylidene (24; 13 kJ mol-1; μ = 7.59 D), 5-methylene-naphthalen-1-ylidene (26; 15 kJ mol-1; μ = 5.32 D), 6-methylene-naphthalen-2-ylidene (27; -43 kJ mol-1; μ = 6.60 D), and 8-methylene-naphthalen-2-ylidene (28; -39 kJ mol-1; μ = 5.55 D) are competitively polar compared to 18 (μ = 5.39 D). Therefore, these carbene molecules are potential targets for rotational spectroscopists and radioastronomers. Considering the importance of naphthyl and azulenylcarbenes in reactive intermediate chemistry, mechanisms of different rearrangement reactions and plausible formation pathways of some of these new carbenes are studied in this work using density functional theory.
Collapse
Affiliation(s)
- Tarun Roy
- Department
of Chemistry, National Institute of Technology
Durgapur, M G Avenue, Durgapur 713
209, India
| | - Venkatesan S. Thimmakondu
- Department
of Chemistry and Biochemistry, San Diego
State University, San Diego, California 92182-1030, United States
| | - Subhas Ghosal
- Department
of Chemistry, National Institute of Technology
Durgapur, M G Avenue, Durgapur 713
209, India
| |
Collapse
|
24
|
Gobre VV, Gejji SP, Pathak RK. Cyclopropenylidene: Clustering and Interaction with Water Molecules. J Phys Chem A 2022; 126:5721-5728. [PMID: 35998414 DOI: 10.1021/acs.jpca.2c03903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cyclopropenylidene (c-C3H2, abbreviated CPD) is a highly reactive, planar, partially aromatic carbene discovered in the interstellar medium, and, also recently, in the outer solar system. It is demonstrated herein on cogent quantum chemical grounds that CPD which possesses an electric dipole moment of 3.4 D is capable of forming stable dimer and trimer clusters through hydrogen-bonding. These attributes of CPD are conducive to the formation of stable hydrogen-bonded conformations with one- and two-water molecules. Having determined its consistency with the second-order Møller-Plesset perturbation theory MP2, we employ the ωB97xD hybrid density functional theory in conjunction with a 6-311++G(2d,2p) basis set for a credible description of noncovalent interactions involved in clustering. Molecular electrostatic potential (MESP) and characteristic vibrational frequency shifts upon clustering are presented.
Collapse
Affiliation(s)
- Vivekanand V Gobre
- School of Chemical Sciences, Goa University, Taleigao, Plateau Goa, 403206, India
| | - Shridhar P Gejji
- Department of Chemistry, Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| | - Rajeev K Pathak
- Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| |
Collapse
|
25
|
Panda S, Sivadasan D, Job N, Sinjari A, Thirumoorthy K, Anoop A, Thimmakondu VS. Why Are MgC 3H Isomers Missing in the Interstellar Medium? J Phys Chem A 2022; 126:4465-4475. [PMID: 35767462 PMCID: PMC9382639 DOI: 10.1021/acs.jpca.2c02220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Considering the recent findings of linear doublet (2Σ+) MgCnH isomers (n = 2, 4, and 6) in the evolved carbon star IRC+10216, various structural isomers of MgC3H and MgC3H+ are theoretically investigated here. For MgC3H, 11 doublet and 8 quartet stationary points ranging from 0.0 to 71.8 and 0.0 to 110.1 kcal mol-1, respectively, have been identified initially at the UωB97XD/6-311++G(2d,2p) level. To get accurate relative energies, further energy evaluations are carried out for all isomers with coupled cluster methods and thermochemical modules such as G3//B3LYP, G4MP2, and CBS-QB3 methods. Unlike the even series, where the global minima are linear molecules with a Mg atom at one end, in the case of MgC3H, the global minimum geometry turns out to be a cyclic isomer, 2-magnesabicyclo[1.1.0]but-1,3,4-triyl (1, C2v, 2A1). In addition, five low-lying isomers, magnesium-substituted cyclopropenylidene (2, Cs, 2A'), 1-magnesabut-2,3-dien-1-yl-4-ylidene (3, Cs, 2A″), 1-magnesabut-2-yn-1-yl-4-ylidene (4, Cs, 2A″), 2λ3-magnesabicyclo[1.1.0]but-1,3-diyl-4-ylidene (5, C2v;, 2A1), and 1-magnesabut-2,3-dien-2-yl-4-ylidene (6, C∞v, 2Σ+), were also identified. The doublet linear isomer of MgC3H, 1-magnesabutatrienyl (10, C∞v, 2Σ+) turns out to be a minimum but lies 54.1 kcal mol-1 above 1 at the ROCCSD(T)/cc-pVTZ level. The quartet (4Σ+) electronic state of 10 was also found to be a minimum, but it lies 8.0 kcal mol-1 above 1 at the same level. Among quartets, isomer 10 is the most stable molecule. The next quartet electronic state (of isomer 11) is 34.4 kcal mol-1 above 10, and all other quartet electronic states of other isomers are not energetically close to low-lying doublet isomers 2 to 6. Overall, the chemical space of MgC3H contains more cyclic isomers (1, 2, and 3) on the low-energy side unlike their even-numbered MgCnH counterparts (n = 2, 4, and 6). Though the quartet electronic state of 10 is linear, it is not the global minimum geometry on the MgC3H potential energy surface. Isomerization pathways among the low-lying isomers (doublets of 1-4 and a quartet of 10) reveal that these molecules are kinetically stable. For the cation, MgC3H+, the cyclic isomers (1+, 2+, and 3+) are on the low-energy side. The singlet linear isomer, 10+, is a fourth-order saddle point. The low-lying cations are quite polar, with dipole moment values of >7.00 D. The current theoretical data would be helpful to both laboratory astrophysicists and radioastronomers for further studies on the MgC3H0/+ isomers.
Collapse
Affiliation(s)
- Sunanda Panda
- Department
of Chemistry, Indian Institute of Technology
Kharagpur, Kharagpur 721 302, West Bengal, India
| | - Devipriya Sivadasan
- Department
of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632 014, Tamil Nadu, India
| | - Nisha Job
- Department
of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632 014, Tamil Nadu, India
| | - Aland Sinjari
- School
of Mathematics, Biological, Exercise & Physical Sciences, San Diego Miramar College, San Diego, California 92126-2910, United States
| | - Krishnan Thirumoorthy
- Department
of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632 014, Tamil Nadu, India
| | - Anakuthil Anoop
- Department
of Chemistry, Indian Institute of Technology
Kharagpur, Kharagpur 721 302, West Bengal, India
| | - Venkatesan S. Thimmakondu
- Department
of Chemistry and Biochemistry, San Diego
State University, San Diego, California 92182-1030, United States
| |
Collapse
|
26
|
The Binary-Encounter-Bethe Model for Computation of Singly Differential Cross Sections Due to Electron-Impact Ionization. ATOMS 2022. [DOI: 10.3390/atoms10020060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In the present work, we assess the effectiveness of singly differential cross sections (SDCS) due to electron-impact ionization by invoking the binary-encounter-Bethe (BEB) model on various atomic and molecular targets. The computed results were compared with the experimental and theoretical data. A good agreement was observed between the present and the available results. This agreement improves as the incident energy of the projectile increases. The model can be applied to compute the SDCS for the ions produced due to the electron-impact dissociative ionization process and the average energy due to the secondary electrons. Both these quantities are of interest in plasma processing and radiation physics.
Collapse
|
27
|
Mogren Al Mogren M, Ben Abdallah D, Dhaif Allah Al Harbi S, Senent ML. Collision excitation of c-C 3H -(X 1A 1) by He. J Chem Phys 2022; 156:184302. [PMID: 35568567 DOI: 10.1063/5.0089458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Accurate modeling of anionic abundances in the interstellar and circumstellar media requires calculations of collisional data with the most abundant species that are usually He atoms and H2 molecules. In this paper, we focus on smaller cyclic molecular anion, c-C3H-, an astrophysical candidate, following the detection of larger CnH- carbon chains. From a new three-dimensional potential energy surface, the rotational (de-)excitation of the c-C3H-(X1A1) anion by collision with He is investigated. The surface is obtained in the supermolecular approach at the CCSD(T)-F12/aug-cc-pVTZ level of theory. Fully quantum close-coupling calculations of inelastic integral cross sections are performed on a grid of collisional energies large enough to ensure the convergence of the state-to-state rate coefficients for the 34 first rotational levels up to jKa,Kc = 77,0 of c-C3H- and temperatures ranging from 5 to 100 K. For this collisional system, rate coefficients exhibit a strong dominance in favor of 21,2 → l1,1 downward transition. This transition was previously used for the detection of the cyclic parent c-C3H. The c-C3H--He rate coefficients (∼10-11 cm3 s-1) are of the same order of magnitude as those of the detected anions CnH- (as C2H-, C4H-, and C6H-) in collision with He and one order of magnitude smaller than those with H2. The critical densities of H2 were also estimated, and a discussion on the validity of the local thermodynamic equilibrium conditions is carried out. This work represents the contribution to understanding and modeling abundances and chemistry of hydrocarbon radicals, CnH, in astrophysical media.
Collapse
Affiliation(s)
- Muneerah Mogren Al Mogren
- Faculty of Science, Department of Chemistry, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Driss Ben Abdallah
- Laboratoire de Physique Moléculaire, Ecole Supérieure des Sciences et Techniques de Tunis, 5 Av. Taha Hussein, Tunis 1008, Tunisia
| | - Sarah Dhaif Allah Al Harbi
- Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University, Riyadh 11623, Saudi Arabia
| | - Maria Luisa Senent
- Departamento de Química y Física Teóricas, Instituto de Estructura de la Materia, IEM-CSIC, Serrano 121, Unidad Asociada GIFMAN, CSIC-UHU, Madrid 28006, Spain
| |
Collapse
|
28
|
Kumar Kushvaha S, Mishra A, Roesky HW, Chandra Mondal K. Recent Advances in the Domain of Cyclic (Alkyl)(Amino) Carbenes. Chem Asian J 2022; 17:e202101301. [PMID: 34989475 PMCID: PMC9307053 DOI: 10.1002/asia.202101301] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/25/2021] [Indexed: 12/03/2022]
Abstract
Isolation of cyclic (alkyl) amino carbenes (cAACs) in 2005 has been a major achievement in the field of stable carbenes due to their better electronic properties. cAACs and bicyclic(alkyl)(amino)carbene (BicAAC) in essence are the most electrophilic as well as nucleophilic carbenes are known till date. Due to their excellent electronic properties in terms of nucleophilic and electrophilic character, cAACs have been utilized in different areas of chemistry, including stabilization of low valent main group and transition metal species, activation of small molecules, and catalysis. The applications of cAACs in catalysis have opened up new avenues of research in the field of cAAC chemistry. This review summarizes the major results of cAAC chemistry published until August 2021.
Collapse
Affiliation(s)
| | - Ankush Mishra
- Department of ChemistryIndian Institute of Technology MadrasChennai600036India
| | - Herbert W. Roesky
- Institute of Inorganic ChemistryTammannstrasse 4D-37077GöttingenGermany
| | | |
Collapse
|
29
|
Goettl SJ, He C, Paul D, Nikolayev AA, Azyazov VN, Mebel AM, Kaiser RI. Gas-Phase Study of the Elementary Reaction of the D1-Ethynyl Radical (C 2D; X 2Σ +) with Propylene (C 3H 6; X 1A') under Single-Collision Conditions. J Phys Chem A 2022; 126:1889-1898. [PMID: 35289624 DOI: 10.1021/acs.jpca.2c00297] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The bimolecular gas-phase reactions of the D1-ethynyl radical (C2D; X2Σ+) with propylene (C3H6; X1A') and partially substituted D3-3,3,3-propylene (C2H3CD3; X1A') were studied under single collision conditions utilizing the crossed molecular beams technique. Combining our laboratory data with electronic structure and statistical calculations, the D1-ethynyl radical is found to add without barrier to the C1 and C2 carbons of the propylene reactant, resulting in doublet C5H6D intermediate(s) with lifetime(s) longer than their rotational period(s). These intermediates undergo isomerization and unimolecular decomposition via atomic hydrogen loss through tight exit transition states forming predominantly cis/trans-3-penten-1-yne ((HCC)CH═CH(CH3)) and, to a minor amount, 3-methyl-3-buten-1-yne ((HCC)C(CH3)═CH2) via overall exoergic reactions. Although the title reaction does not lead to the cyclopentadiene molecule (c-C5H6, X1A1), high-temperature environments can convert the identified acyclic C5H6 isomers through hydrogen atom assisted isomerization to cyclopentadiene (c-C5H6, X1A1). Since both the ethynyl radical and propylene reactants have been observed in cold interstellar environments such as TMC-1 and the reaction is exoergic and all barriers lie below the energy of the separated reactants, these C5H6 product isomers are predicted to form in those low-temperature regions.
Collapse
Affiliation(s)
- Shane J Goettl
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Chao He
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Dababrata Paul
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Anatoliy A Nikolayev
- Lebedev Physical Institute, Samara 443011, Russian Federation.,Samara National Research University, Samara 443086, Russian Federation
| | - Valeriy N Azyazov
- Lebedev Physical Institute, Samara 443011, Russian Federation.,Samara National Research University, Samara 443086, Russian Federation
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
30
|
Abstract
Ground-based telescopes and space exploration have provided outstanding observations of the complexity of icy planetary surfaces. This work presents our review of the varying nature of carbon dioxide (CO2) and carbon monoxide (CO) ices from the cold traps on the Moon to Pluto in the Kuiper Belt. This review is organized into five parts. First, we review the mineral physics (e.g., rheology) relevant to these environments. Next, we review the radiation-induced chemical processes and the current interpretation of spectral signatures. The third section discusses the nature and distribution of CO2 in the giant planetary systems of Jupiter and Saturn, which are much better understood than the satellites of Uranus and Neptune, discussed in the subsequent section. The final sections focus on Pluto in comparison to Triton, having mainly CO, and a brief overview of cometary materials. We find that CO2 ices exist on many of these icy bodies by way of magnetospheric influence, while intermixing into solid ices with CH4 (methane) and N2 (nitrogen) out to Triton and Pluto. Such radiative mechanisms or intermixing can provide a wide diversity of icy surfaces, though we conclude where further experimental research of these ices is still needed.
Collapse
|
31
|
Kanakati AK, Jhansi Rani V, Mahapatra S. The Jahn-Teller and pseudo-Jahn-Teller effects in propyne radical cation. Phys Chem Chem Phys 2022; 24:16522-16537. [DOI: 10.1039/d2cp01930b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Jahn-Teller (JT) and pseudo-Jahn-Teller (PJT) effects in the X 2E, A 2E and B 2A1 electronic states of propyne radical cation are investigated with the aid of ab initio...
Collapse
|
32
|
He C, Fujioka K, Nikolayev AA, Zhao L, Doddipatla S, Azyazov VN, Mebel AM, Sun R, Kaiser RI. A chemical dynamics study of the reaction of the methylidyne radical (CH, X 2Π) with dimethylacetylene (CH 3CCCH 3, X 1A 1g). Phys Chem Chem Phys 2021; 24:578-593. [PMID: 34908056 DOI: 10.1039/d1cp04443e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The gas-phase reaction of the methylidyne (CH; X2Π) radical with dimethylacetylene (CH3CCCH3; X1A1g) was studied at a collision energy of 20.6 kJ mol-1 under single collision conditions with experimental results merged with ab initio calculations of the potential energy surface (PES) and ab initio molecule dynamics (AIMD) simulations. The crossed molecular beam experiment reveals that the reaction proceeds barrierless via indirect scattering dynamics through long-lived C5H7 reaction intermediate(s) ultimately dissociating to C5H6 isomers along with atomic hydrogen with atomic hydrogen predominantly released from the methyl groups as verified by replacing the methylidyne with the D1-methylidyne reactant. AIMD simulations reveal that the reaction dynamics are statistical leading predominantly to p28 (1-methyl-3-methylenecyclopropene, 13%) and p8 (1-penten-3-yne, 81%) plus atomic hydrogen with a significant amount of available energy being channeled into the internal excitation of the polyatomic reaction products. The dynamics are controlled by addition to the carbon-carbon triple bond with the reaction intermediates eventually eliminating a hydrogen atom from the methyl groups of the dimethylacetylene reactant forming 1-methyl-3-methylenecyclopropene (p28). The dominating pathways reveal an unexpected insertion of methylidyne into one of the six carbon-hydrogen single bonds of the methyl groups of dimethylacetylene leading to the acyclic intermediate, which then decomposes to 1-penten-3-yne (p8). Therefore, the methyl groups of dimethylacetylene effectively 'screen' the carbon-carbon triple bond from being attacked by addition thus directing the dynamics to an insertion process as seen exclusively in the reaction of methylidyne with ethane (C2H6) forming propylene (CH3C2H3). Therefore, driven by the screening of the triple bond, one propynyl moiety (CH3CC) acts in four out of five trajectories as a spectator thus driving an unexpected, but dominating chemistry in analogy to the methylidyne - ethane system.
Collapse
Affiliation(s)
- Chao He
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Kazuumi Fujioka
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Anatoliy A Nikolayev
- Lebedev Physical Institute, Samara 443011, Russia.,Samara National Research University, Samara 443086, Russia
| | - Long Zhao
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Srinivas Doddipatla
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Valeriy N Azyazov
- Lebedev Physical Institute, Samara 443011, Russia.,Samara National Research University, Samara 443086, Russia
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, USA.
| | - Rui Sun
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| |
Collapse
|
33
|
Matsuda A, Tani K, Takeuchi Y, Hayakawa Y, Hishikawa A. Association Reaction of Gaseous C 2H 4 in Femtosecond Laser Filaments Studied by Time-of-Flight Mass Spectrometry. ACS OMEGA 2021; 6:29862-29868. [PMID: 34778659 PMCID: PMC8582076 DOI: 10.1021/acsomega.1c04354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/30/2021] [Indexed: 06/13/2023]
Abstract
Association reactions by femtosecond laser filamentation in gaseous C2H4 were studied by time-of-flight mass spectrometry of neutral reaction products. Direct sampling from the reaction cell to a mass spectrometer via a differential pumping stage allowed the identification of various hydrocarbon molecules C n H m with n = 3-7 and m = 4-7, which includes species not observed in the previous studies. It was found that products containing three and four carbon atoms dominate the mass spectrum with smaller yields for higher-mass species, suggesting that carbon chain growth proceeds through the reaction with C2H4 in the reaction cell. The product distribution showed a clear dependence on the laser pulse energy for filamentation.
Collapse
Affiliation(s)
- Akitaka Matsuda
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Kentaro Tani
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Yukari Takeuchi
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Yui Hayakawa
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Akiyoshi Hishikawa
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
- Research
Center for Materials Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| |
Collapse
|
34
|
Volosatova AD, Lukianova MA, Zasimov PV, Feldman VI. Direct evidence for a radiation-induced synthesis of acetonitrile and isoacetonitrile from a 1 : 1 CH 4HCN complex at cryogenic temperatures: is it a missing link between inorganic and prebiotic astrochemistry? Phys Chem Chem Phys 2021; 23:18449-18460. [PMID: 34612385 DOI: 10.1039/d1cp01598b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nitriles are important constituents of extraterrestrial media. Nitriles are supposed to play a crucial role in prebiotic chemistry occurring in the interstellar medium. In this work, we have investigated the low-temperature radiation-induced transformations of a 1 : 1 CH4HCN complex as a plausible precursor of the simplest nitriles using the matrix isolation approach with FTIR spectroscopic detection. The parent complexes isolated in a noble gas (Ng) matrix were obtained by deposition of the CH4/HCN/Ng gaseous mixture and characterized by comparison of experimental complexation-induced shifts of the HCN fundamentals with the results of the ab initio calculations. It was found that the X-ray irradiation of low-temperature matrices containing the isolated 1 : 1 CH4HCN complex resulted in the formation of acetonitrile (CH3CN) and isoacetonitrile (CH3NC) and it appears to be the first experimental evidence for the formation of C2 nitriles (acetonitrile and isoacetonitrile) from such a "building block". Additionally, a 1 : 1 CH4HNC complex was tentatively assigned to the irradiated Ar and Kr matrices. It is demonstrated that the matrix has a strong effect on the CH3CN/CH3NC yield ratio, which dramatically increases in the row Ar < Kr < Xe. Also, the efficiency of the radiation-induced formation of the CH4HNC complex was shown to decrease from Ar to Kr. It is believed that the proposed pathway for acetonitrile formation may be a significant step in the radiation-induced evolution leading to complex organic molecules and biomolecules under astrochemical conditions. Furthermore, the obtained results provide a prominent example of the impact of very weak intermolecular interactions on the radiation-induced transformations in cold media.
Collapse
|
35
|
Goettl SJ, Yang Z, Doddipatla S, He C, Alves MO, Galvão BRL, Kaiser RI. A Crossed Molecular Beams and Computational Study of the Formation of the Astronomically Elusive Thiosilaformyl Radical (HSiS, X 2A'). J Phys Chem Lett 2021; 12:5979-5986. [PMID: 34161096 DOI: 10.1021/acs.jpclett.1c01706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The formation pathways to silicon- and sulfur-containing molecules are crucial to the understanding of silicon-sulfur chemistry in interstellar and circumstellar environments. While multiple silicon- and sulfur-containing species have been observed in deep space, their fundamental formation mechanisms are largely unknown. The crossed molecular beams technique combined with electronic structure and Rice-Ramsperger-Kassel-Marcus (RRKM) calculations was utilized to study the bimolecular reaction of atomic silicon (Si(3Pj)) with thiomethanol (CH3SH, X1A') leading to the thiosilaformyl radical (HSiS, X2A') via an exclusive methyl radical (CH3, X2A2″) loss via indirect scattering dynamics which involves barrierless addition and hydrogen migration in an overall exoergic reaction, indicating the possibility that HSiS can form in cold molecular clouds. The astronomically elusive thiosilaformyl radical may act as a tracer of an exotic silicon-sulfur chemistry to be deciphered toward, for example, the star-forming region SgrB2, thus leading to a better understanding of the formation of silicon-sulfur bonds in deep space.
Collapse
Affiliation(s)
- Shane J Goettl
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Srinivas Doddipatla
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Chao He
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| | - Márcio O Alves
- Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Av. Amazonas 5253, 30421-169 Belo Horizonte, Minas Gerais, Brazil
| | - Breno R L Galvão
- Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Av. Amazonas 5253, 30421-169 Belo Horizonte, Minas Gerais, Brazil
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
36
|
Yang Z, He C, Goettl S, Kaiser RI. Reaction Dynamics Study of the Molecular Hydrogen Loss Channel in the Elementary Reactions of Ground-State Silicon Atoms (Si( 3P)) With 1- and 2-Methyl-1,3-Butadiene (C 5H 8). J Phys Chem A 2021; 125:5040-5047. [PMID: 34096290 DOI: 10.1021/acs.jpca.1c03023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The bimolecular gas-phase reactions involving ground-state atomic silicon (Si; 3P) and 1- and 2-methyl-1,3-butadiene were studied via crossed molecular beam experiments. Our data revealed indirect scattering dynamics through long-lived SiC5H8 collision complex(es) along with molecular hydrogen loss pathways, leading to facile formation of SiC5H6 isomer(s). We propose that the reactions of silicon with 1- and 2-methyl-1,3-butadiene possess reaction dynamics in an analogy to the silicon-1,3-butadiene system. This leads to cyclic methyl-substituted 2-methylene-1-silacyclobutene isomers via nonadiabatic reaction dynamics through intersystem crossing (ISC) from the triplet to the singlet surface in overall exoergic reactions through tight exit transition states and molecular hydrogen loss. Our study also suggests that the methyl group-although a spectator from the chemical viewpoint-can influence the disposal of the angular momentum into the rotational excitation of the final product.
Collapse
Affiliation(s)
- Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Chao He
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Shane Goettl
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
37
|
Zhao L, Lu W, Ahmed M, Zagidullin MV, Azyazov VN, Morozov AN, Mebel AM, Kaiser RI. Gas-phase synthesis of benzene via the propargyl radical self-reaction. SCIENCE ADVANCES 2021; 7:7/21/eabf0360. [PMID: 34020951 PMCID: PMC8139581 DOI: 10.1126/sciadv.abf0360] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 03/31/2021] [Indexed: 06/01/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) have been invoked in fundamental molecular mass growth processes in our galaxy. We provide compelling evidence of the formation of the very first ringed aromatic and building block of PAHs-benzene-via the self-recombination of two resonantly stabilized propargyl (C3H3) radicals in dilute environments using isomer-selective synchrotron-based mass spectrometry coupled to theoretical calculations. Along with benzene, three other structural isomers (1,5-hexadiyne, fulvene, and 2-ethynyl-1,3-butadiene) and o-benzyne are detected, and their branching ratios are quantified experimentally and verified with the aid of computational fluid dynamics and kinetic simulations. These results uncover molecular growth pathways not only in interstellar, circumstellar, and solar systems environments but also in combustion systems, which help us gain a better understanding of the hydrocarbon chemistry of our universe.
Collapse
Affiliation(s)
- Long Zhao
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Wenchao Lu
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Musahid Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | | | - Valeriy N Azyazov
- Lebedev Physical Institute, Samara 443011, Russian Federation
- Samara National Research University, Samara 443086, Russian Federation
| | - Alexander N Morozov
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
| |
Collapse
|
38
|
Wang Y, Wang E, Zhou J, Dorn A, Ren X. Formation of covalently bound C 4H 4 + upon electron-impact ionization of acetylene dimer. J Chem Phys 2021; 154:144301. [PMID: 33858144 DOI: 10.1063/5.0045531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We investigate the formation mechanisms of covalently bound C4H4 + cations from direct ionization of hydrogen bonded dimers of acetylene molecules through fragment ion and electron coincident momentum spectroscopy and quantum chemistry calculations. The measurements of momenta and energies of two outgoing electrons and one ion in triple-coincidence allow us to assign the ionization channels associated with different ionic fragments. The measured binding energy spectra show that the formation of C4H4 + can be attributed to the ionization of the outermost 1πu orbital of acetylene. The kinetic energy distributions of the ionic fragments indicate that the C4H4 + ions originate from direct ionization of acetylene dimers while ions resulting from the fragmentation of larger clusters would obtain significantly larger momenta. The formation of C4H4 + through the evaporation mechanism in larger clusters is not identified in the present experiments. The calculated potential energy curves show a potential well for the electronic ground state of (C2H2)2+, supporting that the ionization of (C2H2)2 dimers can form stable C2H2⋅C2H2 +(1πu -1) cations. Further transition state analysis and ab initio molecular dynamics simulations reveal a detailed picture of the formation dynamics. After ionization of (C2H2)2, the system undergoes a significant rearrangement of the structure involving, in particular, C-C bond formation and hydrogen migrations, leading to different C44+ isomers.
Collapse
Affiliation(s)
- Yingying Wang
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an 710049, China
| | - Enliang Wang
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - Jiaqi Zhou
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an 710049, China
| | - Alexander Dorn
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - Xueguang Ren
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an 710049, China
| |
Collapse
|
39
|
Ferrari BC, Slavicinska K, Bennett CJ. Role of Suprathermal Chemistry on the Evolution of Carbon Oxides and Organics within Interstellar and Cometary Ices. Acc Chem Res 2021; 54:1067-1079. [PMID: 33554606 DOI: 10.1021/acs.accounts.0c00731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
ConspectusLaboratory-based experimental astrochemistry regularly entails simulation of astrophysical environments whereby low-temperature condensed ices are exposed to radiation from ultraviolet (UV) photons or energetic charged particles. Here, excited atoms/radicals are generated that are not in thermal equilibrium with their surroundings (i.e., they are nonthermal, or suprathermal). These species can surpass typical reaction barriers and partake in unusual chemical processes leading to novel molecular species. Often, these are uniquely observable under low-temperature conditions where the surrounding ice matrix can stabilize excited intermediates that would otherwise fall apart. Fourier-transform infrared (FTIR) spectroscopy is traditionally utilized to monitor the evolution of chemical species within ices in situ during radiolysis. Yet, the characterization and quantification of novel species and radicals formed within astrophysical ices is often hindered since many of these cannot be synthesized by traditional synthetic chemistry. Computational approaches can provide fundamental vibrational frequencies and isotopic shifts to help aid in assignments alongside infrared intensities and Raman activities to quantify levels of production. In this Account, we begin with a brief history and background regarding the composition and radiation of interstellar ices. We review details of some of the early work on carbon oxides produced during the radiolysis of pure carbon dioxide ices and contention around the carrier of an absorption feature that could potentially be a product of radiation. We then provide an overview of current and emerging experimental methodologies and some of the chemistries that occur via nonthermal processes during radiolysis of low-temperature ices. Next, we detail computational approaches to reliably predict vibrational frequencies, infrared intensities, and Raman activities based on our recent work. Our focus then turns to studies on the formation of complex organics and carbon oxides, highlighting those aided by computational approaches and their role in astrochemistry. Some recent controversies regarding assignments alongside our recent results on the characterization of novel carbon oxide species are discussed. We present an argument for the potential role of carbon oxides within cometary ices as parent molecular species for small volatiles. We provide an overview of some of the complex organic species that can be formed within interstellar and cometary ices that contain either carbon monoxide or carbon dioxide. We examine how Raman spectroscopy could potentially be leveraged to help determine and characterize carbon oxides in future experiments as well as how computational approaches can aid in these assignments. We conclude with brief remarks on future directions our research group is taking to unravel astrochemically relevant carbon oxides using combined computational and experimental approaches.
Collapse
Affiliation(s)
- Brian C. Ferrari
- Department of Physics, University of Central Florida, Orlando, Florida 32816, United States
| | - Katerina Slavicinska
- Department of Physics, University of Central Florida, Orlando, Florida 32816, United States
| | - Christopher J. Bennett
- Department of Physics, University of Central Florida, Orlando, Florida 32816, United States
| |
Collapse
|
40
|
A vacuum ultraviolet photoionization study on the isomerization, decomposition, and molecular mass growth processes in solid nitromethane (CH3NO2). Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.138343] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
41
|
Woon DE. Quantum Chemical Cluster Studies of Cation-Ice Reactions for Astrochemical Applications: Seeking Experimental Confirmation. Acc Chem Res 2021; 54:490-497. [PMID: 33444014 DOI: 10.1021/acs.accounts.0c00717] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
ConspectusInterstellar clouds and the outer reaches of protostellar and protoplanetary systems are very cold environments where chemistry is limited to processes that have little or no reaction barrier (in the absence of external energy input). This account reviews what is known about cation-ice reactions, which are not currently incorporated in astrochemical network models. Quantum chemical cluster calculations using density functional theory have shown that barrierless reactions can occur when gas phase cations such as HCO+, OH+, CH3+, and C+ are deposited on an icy grain mantle with energies commensurate with other gas phase species. When cations react with molecules on ice surfaces, the pathways and products often differ significantly from gas phase chemistry due to the involvement of water and other molecules in the ice. The reactions studied to date have found pathways to abundant and important astromolecules such as methanol, formic acid, and carbon dioxide that are very favorable and may be more efficient pathways than gas phase processes. Other products that can be produced include glycolonitrile, its precursors, and related isocyanide compounds. This account describes for the first time ice surface reactions between the carbon cation, C+, and two common astromolecules, methanol (CH3OH) and formic acid (HCOOH), which can yield precursors to glyoxal, hydroxyketene, vinyl alcohol, and acetaldehyde. The quantum chemical methodology used to explore reaction surfaces is also used to predict both vibrational and electronic spectra of reactant and product ices, which offers guidance for possible experimental studies of these reactions. While theoretical calculations indicate that cation-ice reactions are efficient and offer novel pathways to important astrochemical compounds, experimental confirmation would be very welcome. Cations and ice-covered grain mantles are certainly present in cold astrophysical environments. The account concludes with a discussion of how cation-ice reactions could be incorporated into reaction network models of the formation and destruction of molecules in interstellar clouds and protoplanetary systems. Further studies will involve characterizing additional rcactions and more extensive treatment of the most important cation-ice reactions to better ascertain reaction branching outcomes.
Collapse
Affiliation(s)
- David E. Woon
- Department of Chemistry, University of Illinois at Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| |
Collapse
|
42
|
Yang Z, Doddipatla S, Kaiser RI, Krasnoukhov VS, Azyazov VN, Mebel AM. Directed Gas Phase Formation of the Elusive Silylgermylidyne Radical (H 3 SiGe, X 2 A''). Chemphyschem 2021; 22:184-191. [PMID: 33245830 DOI: 10.1002/cphc.202000913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/25/2020] [Indexed: 11/11/2022]
Abstract
The previously unknown silylgermylidyne radical (H3 SiGe; X2 A'') was prepared via the bimolecular gas phase reaction of ground state silylidyne radicals (SiH; X2 Π) with germane (GeH4 ; X1 A1 ) under single collision conditions in crossed molecular beams experiments. This reaction begins with the formation of a van der Waals complex followed by insertion of silylidyne into a germanium-hydrogen bond forming the germylsilyl radical (H3 GeSiH2 ). A hydrogen migration isomerizes this intermediate to the silylgermyl radical (H2 GeSiH3 ), which undergoes a hydrogen shift to an exotic, hydrogen-bridged germylidynesilane intermediate (H3 Si(μ-H)GeH); this species emits molecular hydrogen forming the silylgermylidyne radical (H3 SiGe). Our study offers a remarkable glance at the complex reaction dynamics and inherent isomerization processes of the silicon-germanium system, which are quite distinct from those of the isovalent hydrocarbon system (ethyl radical; C2 H5 ) eventually affording detailed insights into an exotic chemistry and intriguing chemical bonding of silicon-germanium species at the microscopic level exploiting crossed molecular beams.
Collapse
Affiliation(s)
- Zhenghai Yang
- Department of Chemistry, University of Hawaii, Honolulu, HI, 96822, USA
| | | | - Ralf I Kaiser
- Department of Chemistry, University of Hawaii, Honolulu, HI, 96822, USA
| | - Vladislav S Krasnoukhov
- Samara National Research University, Samara 443086 and Lebedev Physical Institute, Samara, 443011, Russian Federation
| | - Valeriy N Azyazov
- Samara National Research University, Samara 443086 and Lebedev Physical Institute, Samara, 443011, Russian Federation
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| |
Collapse
|
43
|
Goettl SJ, Doddipatla S, Yang Z, He C, Kaiser RI, Silva MX, Galvão BRL, Millar TJ. Chemical dynamics study on the gas-phase reaction of the D1-silylidyne radical (SiD; X 2Π) with deuterium sulfide (D 2S) and hydrogen sulfide (H 2S). Phys Chem Chem Phys 2021; 23:13647-13661. [PMID: 34120159 DOI: 10.1039/d1cp01629f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactions of the D1-silylidyne radical (SiD; X2Π) with deuterium sulfide (D2S; X1A1) and hydrogen sulfide (H2S; X1A1) were conducted utilizing a crossed molecular beams machine under single collision conditions. The experimental work was carried out in conjunction with electronic structure calculations. The elementary reaction commences with a barrierless addition of the D1-silylidyne radical to one of the non-bonding electron pairs of the sulfur atom of hydrogen (deuterium) sulfide followed by possible bond rotation isomerization and multiple atomic hydrogen (deuterium) migrations. Unimolecular decomposition of the reaction intermediates lead eventually to the D1-thiosilaformyl radical (DSiS) (p1) and D2-silanethione (D2SiS) (p3) via molecular and atomic deuterium loss channels (SiD-D2S system) along with the D1-thiosilaformyl radical (DSiS) (p1) and D1-silanethione (HDSiS) (p3) through molecular and atomic hydrogen ejection (SiD-H2S system) via indirect scattering dynamics in barrierless and overall exoergic reactions. Our study provides a look into the complex dynamics of the silicon and sulfur chemistries involving multiple deuterium/hydrogen shifts and tight exit transition states, as well as insight into silicon- and sulfur-containing molecule formation pathways in deep space. Although neither of the non-deuterated species - the thiosilaformyl radical (HSiS) and silanethione (H2SiS) - have been observed in the interstellar medium (ISM) thus far, astrochemical models presented here predict relative abundances in the Orion Kleinmann-Low nebula to be sufficiently high enough for detection.
Collapse
Affiliation(s)
- Shane J Goettl
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Srinivas Doddipatla
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Zhenghai Yang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Chao He
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Mateus X Silva
- Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Av. Amazonas 5253, 30421-169 Belo Horizonte, Minas Gerais, Brazil.
| | - Breno R L Galvão
- Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Av. Amazonas 5253, 30421-169 Belo Horizonte, Minas Gerais, Brazil.
| | - Tom J Millar
- School of Maths and Physics, Queen's University Belfast, University Road, Belfast BT7 1NN, Northern Ireland, UK.
| |
Collapse
|
44
|
Turner AM, Kaiser RI. Exploiting Photoionization Reflectron Time-of-Flight Mass Spectrometry to Explore Molecular Mass Growth Processes to Complex Organic Molecules in Interstellar and Solar System Ice Analogs. Acc Chem Res 2020; 53:2791-2805. [PMID: 33258604 DOI: 10.1021/acs.accounts.0c00584] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
ConspectusThis Account presents recent advances in our understanding on the formation pathways of complex organic molecules (COMs) within interstellar analog ices on ice-coated interstellar nanoparticles upon interaction with ionizing radiation exploiting reflectron time-of-flight mass spectrometry (ReTOF-MS) coupled with tunable vacuum ultraviolet (VUV) single photon ionization (PI) and resonance enhanced multiphoton ionization (REMPI) of the subliming molecules during the temperature-programmed desorption (TPD) phase. Laboratory simulation experiments provided compelling evidence that key classes of complex organics (aromatic hydrocarbons, alcohols, ethers, aldehydes, enols, ketones, and carboxylic acids) can be synthesized upon exposure of astrophysically relevant model ices to ionizing radiation within and throughout the ices at temperatures as low as 5 K.Molecular mass growth processes can be initiated by suprathermal or electronically excited reactants along with barrierless radical-radical recombination if both radicals hold a proper recombination geometry. Methyl (CH3), amino (NH2), hydroxyl (OH), ethyl (C2H5), vinyl (C2H3), ethynyl (C2H), formyl (HCO), hydroxycarbonyl (HOCO), hydroxymethyl (CH2OH), methoxy (CH3O), and acetyl (CH3CO) represent readily available reactants for radical-radical recombination within the ices. Reactive singlet species were found to insert without barrier into carbon-hydrogen and carbon-carbon single bonds (carbene) leading to an extension of the carbon chain and may add to carbon-carbon double bonds (carbene, atomic oxygen) forming cyclic reaction products. These galactic cosmic ray-triggered nonequilibrium pathways overcome previous obstacles of hypothesized thermal grain-surface processes and operate throughout the ice at 5 K. Our investigations discriminate between multiple structural isomers such as alcohols/ethers, aldehydes/enols, and cyclic/acyclic carbonyls. These data provide quantitative, isomer selective input parameters for a cosmic ray-dictated formation of complex organics in interstellar ices and are fully able to replicate the astronomical observations of complex organics over typical lifetimes of molecular clouds of a few 106 to 107 years. Overall, PI-ReTOF-MS revealed that the processing of astrophysically relevant ices can lead to multifaceted mixtures of organics reaching molecular weights of up to 200 amu. Further advances in laboratory techniques beyond the FTIR-QMS limit are clearly desired not only to confidently assign detection in laboratory ice analog experiments of increasingly more complex molecules of interest but also from the viewpoint of future astronomical searches in the age of the Atacama Large Millimeter/submillimeter Array (ALMA).
Collapse
Affiliation(s)
- Andrew M. Turner
- Department of Chemistry and W.M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
| | - Ralf I. Kaiser
- Department of Chemistry and W.M. Keck Research Laboratory in Astrochemistry, University of Hawai’i at Manoa, Honolulu, Hawaii 96822, United States
| |
Collapse
|
45
|
Simbizi R, Gahungu G, Nguyen MT. Theoretical investigation of protonated thiophene and two of its nitrile substituted derivatives (2-cyanothiophene and 3-cyanothiophene). Phys Chem Chem Phys 2020; 22:24735-24743. [PMID: 33107518 DOI: 10.1039/d0cp03154b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Theoretical and experimental spectroscopic data for protonated cyano-thiophenes (R-CNH+ with R = C4H3S), which are needed for their interstellar search and/or detection, are still lacking in the literature. Considering the high abundance and reactivity of H3+ in the interstellar medium (ISM), a quantum chemical investigation on protonated thiophene and two of its nitrile-substituted derivatives (2-cyanothiophene and 3-cyanothiophene) is undertaken for their characterization. The geometrical structures for the title species are calculated at the M06-2X/6-31G(d,p) level of theory, followed by an empirical correction for systematic errors. At the same level of theory, IR and Raman spectra are explored and the rotational parameters are calculated. The proton affinity (PA) of R-CN and the enthalpy, entropy and Gibbs free energy changes (ΔrH, ΔrS and ΔrG) of the reactions producing R-CNH+ are computed at the G2(MP2) and G3B3 levels of theory and at different temperatures. The PA calculations show that the protonation favors the nitrogen atom, while ΔrH, ΔrS, and ΔrG reveal the spontaneous reactions producing R-CNH+ and their neutral forms. In addition, quadrupole hyperfine structures are predicted, while the region where the brightest lines fall at different temperatures is discussed. These results are expected to assist astrophysicists and astrochemists in the search for new species in the ISM.
Collapse
Affiliation(s)
- René Simbizi
- Département de Physique, Faculté des Sciences Université du Burundi, B.P. 2700 Bujumbura, Burundi.
| | | | | |
Collapse
|
46
|
Doud EA, Starr RL, Kladnik G, Voevodin A, Montes E, Arasu NP, Zang Y, Zahl P, Morgante A, Venkataraman L, Vázquez H, Cvetko D, Roy X. Cyclopropenylidenes as Strong Carbene Anchoring Groups on Au Surfaces. J Am Chem Soc 2020; 142:19902-19906. [DOI: 10.1021/jacs.0c10743] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Gregor Kladnik
- CNR-IOM Laboratorio Nazionale TASC, Basovizza
SS-14, km 163.5, 34149 Trieste, Italy
- Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
| | | | - Enrique Montes
- Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, Prague 16200, Czech Republic
| | - Narendra P. Arasu
- Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, Prague 16200, Czech Republic
| | | | - Percy Zahl
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Alberto Morgante
- CNR-IOM Laboratorio Nazionale TASC, Basovizza
SS-14, km 163.5, 34149 Trieste, Italy
- Department of Physics, University of Trieste, via A. Valerio 2, 34127 Trieste, Italy
| | | | - Héctor Vázquez
- Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, Prague 16200, Czech Republic
| | - Dean Cvetko
- CNR-IOM Laboratorio Nazionale TASC, Basovizza
SS-14, km 163.5, 34149 Trieste, Italy
- Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
- J. Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| | | |
Collapse
|
47
|
Thermal unimolecular reactivity pathways in dehydro‐diazines radicals. J PHYS ORG CHEM 2020. [DOI: 10.1002/poc.4152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
48
|
|
49
|
Pandey AP, Padidela UK, Thulasiraman LK, Sethu R, Vairaprakash P, Thimmakondu VS. MgC 6H 2 Isomers: Potential Candidates for Laboratory and Radioastronomical Studies. J Phys Chem A 2020; 124:7518-7525. [PMID: 32804506 DOI: 10.1021/acs.jpca.0c06401] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Eighty three stationary points of MgC6H2 isomers spanning from 0 to 215 kcal mol-1 have been theoretically identified using density functional theory at the B3LYP/6-311++G(2d,2p) level of theory. Among them, four low-lying isomers lying within 23.06 kcal mol-1 (1 eV) have been further characterized in detail using high-level coupled-cluster (CC) methods. The thermodynamically most stable isomer turns out to be 1-magnesacyclohepta-4-en-2,6-diyne (1). The other three isomers, 3-magnesahepta-1,4,6-triyne (2), 1-magnesacyclohepta-2,3,4-trien-6-yne (3), and 1-magnesahepta-2,4,6-triyne (4) lie 8.24, 19.76, and 21.36 kcal mol-1, respectively, above 1 at the ae-CCSD(T)/cc-pCVTZ level of theory. All the four isomers are polar with a permanent electric dipole moment (μ ≠ 0). Hence, they are potential candidates for rotational spectroscopic studies. Considering the recent identification of magnesium-bearing hydrocarbons such as, MgC2H and MgC4H in IRC+10216, it is believed that the current theoretical data may be of relevance to laboratory molecular spectroscopic and radioastronomical studies on MgC6H2 isomers. The energetic and spectroscopic information gathered in this study would aid the detection of low-lying MgC6H2 isomers in the laboratory, which are indispensable for radioastronomical studies. It is also noted here that neither the National Institute of Standards and Technology Chemistry WebBook nor the Kinetic Database for Astrochemistry lists any isomer of MgC6H2 at the moment. Therefore, these isomers are studied here theoretically for the very first time.
Collapse
Affiliation(s)
- Aditya P Pandey
- Electrical and Computer Engineering, College of Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States.,Department of Chemistry, Birla Institute of Technology and Science, Pilani, K K Birla Goa Campus, Goa - 403 726, India
| | - Uday Kumar Padidela
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, K K Birla Goa Campus, Goa - 403 726, India
| | - Loganathan Konda Thulasiraman
- Department of Chemistry, Alagappa Chettiar Government College of Engineering and Technology, Karaikudi 630 003, Tamil Nadu, India
| | - Ramakrishnan Sethu
- Department of Microbiology, University of Illinois, 601 South Goodwin Avenue, Urbana, Illinois 61801, United States
| | - Pothiappan Vairaprakash
- Department of Chemistry, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur - 613 401, Tamil Nadu, India
| | - Venkatesan S Thimmakondu
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182-1030, United States
| |
Collapse
|
50
|
Mondal K, Rajakumar B. Kinetic Investigations of the Reaction of Phenyl Radicals with Ethyl Acetate in the Gas Phase: An Experimental and Computational Study. J Phys Chem A 2020; 124:5503-5512. [PMID: 32539397 DOI: 10.1021/acs.jpca.0c03872] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cavity ring-down spectroscopy (CRDS) was employed to investigate the kinetics of the reaction between phenyl radicals (C6H5•) and ethyl acetate (EtOAc) in the gas phase. Nitrosobenzene (C6H5NO) was used as the radical precursor to generate C6H5• at 248 nm, and the generated radicals were subsequently probed at 504.8 nm. The rate coefficients were investigated experimentally in the temperature range of 258-358 K with an interval of 20 K and at a total pressure of 55 Torr in the nitrogen atmosphere. The obtained Arrhenius expression for the title reaction (C6H5• + EtOAc) in the temperature range of 258-358 K was kphenyl + EtOAcExpt - (258 - 358 K) = (9.33 ± 0.11) × 10-16 exp[(883.7 ± 181.0)/T] cm3 molecule-1 s-1, and the rate coefficient at room temperature (298 K) was kphenyl + EtOAcExpt - 298 K = (2.20 ± 0.12) × 10-14 cm3 molecule-1 s-1. Negligible effects of pressure and photolysis laser fluence were found on the experimentally measured rate coefficients. To complement our experimental findings, rate coefficients of the title reaction were computationally investigated employing the canonical variational transition-state theory with small curvature tunnelling (CVT/SCT) at the CCSD(T)/cc-pVDZ//B3LYP/6-31+G(d,p) level of theory in the temperature range of 200-400 K. The temperature-dependent rate coefficient in the studied temperature range was obtained to be kphenyl + EtOAcTheory - (200 - 400 K) = (7.68 ± 0.12) × 10-17 exp[(1731.6 ± 216.0)/T] cm3 molecule-1 s-1, and the rate coefficient at 298 K was obtained as kphenyl + EtOAcTheory - 298 K = 2.45 × 10-14 cm3 molecule-1 s-1. Both the experimentally measured and computed rate coefficients show good agreement at 298 K. A negative temperature dependency was observed for both the experimentally measured and computed rate coefficients. A detailed discussion of the thermochemical parameters and branching ratios of the title reaction are also presented in this Article.
Collapse
Affiliation(s)
- Koushik Mondal
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | - B Rajakumar
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| |
Collapse
|