1
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Li J, Li Y, Wu B, Xie M, Hu Y. Proton Transfer Processes in 2-Butenenitrile Dimer Cation Studied by Mass-Selective Infrared Spectroscopy. J Phys Chem A 2024; 128:4694-4700. [PMID: 38833155 DOI: 10.1021/acs.jpca.4c01989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
2-Butenenitrile (2-Bu) is a recently discovered crucial interstellar molecule. Herein, an abnormal NH band was observed in the infrared spectrum of the 2-Bu dimer cation, suggestive of a proton transfer reaction within the cluster. Through a comprehensive theoretical analysis of the IR spectrum of (2-Bu)2+, we discovered not only the formation of a new C-N bond through the attachment of one 2-Bu to another but also the occurrence of a proton transfer reaction in the cluster. This proton was identified as originating from the methyl group of the attaching 2-Bu in the cluster based on the analysis of IR spectra of (2-Bu)+ and [2-Bu-acrylonitrile (AN)]+. Furthermore, the detailed reaction process of this ion-molecule reaction is examined with theoretical calculation. This finding contributes significantly to our deeper understanding of ion-molecule reactions in the gas phase and the formation of nitrogen-containing prebiotic molecules in the interstellar medium.
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Affiliation(s)
- Jingyu 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
| | - 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
| | - Bingbing Wu
- 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
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2
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Xiong X, Hu Y. Infrared Spectroscopy of Neutral and Cationic Benzonitrile-Methanol Binary Clusters in Supersonic Jets. Molecules 2024; 29:2744. [PMID: 38930810 PMCID: PMC11206090 DOI: 10.3390/molecules29122744] [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: 06/01/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
The formation of nitrogen-containing organic interstellar molecules is of great importance to reveal chemical processes and the origin of life on Earth. Benzonitrile (BN) is one of the simplest nitrogen-containing aromatic molecules in the interstellar medium (ISM) that has been detected in recent years. Methanol (CH3OH) exists widely in interstellar space with high reactivity. Herein, we measured the infrared (IR) spectra of neutral and cationic BN-CH3OH clusters by vacuum ultraviolet (VUV) photoionization combined with time-of-flight mass spectrometry. Combining IR spectra with the density functional theory calculations, we reveal that the BN-CH3OH intends to form a cyclic H-bonded structure in neutral clusters. However, after the ionization of BN-CH3OH clusters, proton-shared N···H···O and N···H···C structures are confirmed to form between BN and CH3OH, with the minor coexistence of H-bond and O-π structures. The formation of the proton-shared structure expands our knowledge of the evolution of the life-related nitrogen-containing molecules in the universe and provides a possible pathway to the further study of biorelevant aromatic organic macromolecules.
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Affiliation(s)
| | - 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
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3
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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.
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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.
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4
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Mougkogiannis P, Adamatzky A. Proto-neural networks from thermal proteins. Biochem Biophys Res Commun 2024; 709:149725. [PMID: 38579617 DOI: 10.1016/j.bbrc.2024.149725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/25/2024] [Indexed: 04/07/2024]
Abstract
Proteinoids are synthetic polymers that have structural similarities to natural proteins, and their formation is achieved through the application of heat to amino acid combinations in a dehydrated environment. The thermal proteins, initially synthesised by Sidney Fox during the 1960s, has the ability to undergo self-assembly, resulting in the formation of microspheres that resemble cells. These microspheres have fascinating biomimetic characteristics. In recent studies, substantial advancements have been made in elucidating the electrical signalling phenomena shown by proteinoids, hence showcasing their promising prospects in the field of neuro-inspired computing. This study demonstrates the advancement of experimental prototypes that employ proteinoids in the construction of fundamental neural network structures. The article provides an overview of significant achievements in proteinoid systems, such as the demonstration of electrical excitability, emulation of synaptic functions, capabilities in pattern recognition, and adaptability of network structures. This study examines the similarities and differences between proteinoid networks and spontaneous neural computation. We examine the persistent challenges associated with deciphering the underlying mechanisms of emergent proteinoid-based intelligence. Additionally, we explore the potential for developing bio-inspired computing systems using synthetic thermal proteins in forthcoming times. The results of this study offer a theoretical foundation for the advancement of adaptive, self-assembling electronic systems that operate using artificial bio-neural principles.
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5
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Chen X, Wei C, Xie M, Hu Y. Single-Photon Ionization Induced New Covalent Bond Formation in Acrylonitrile(AN)-Pyrrole(Py) Clusters. J Phys Chem A 2023; 127:8272-8279. [PMID: 37769120 DOI: 10.1021/acs.jpca.3c02481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
The formation of nitrogen-containing organic compounds is crucial for understanding chemical evolution and the origin of life in the interstellar medium (ISM). In this study, we explore whether acrylonitrile (AN) and pyrrole (Py) can form new nitrogen-containing compounds after single-photon ionization in their gaseous clusters by vacuum ultraviolet (VUV)-infrared (IR) spectroscopy and theoretical calculations. The results show that a strong linear H-bond is formed in neutral AN-Py, while cyclic or bicyclic H-bonded networks are formed in the neutral AN-Py2 cluster. It is found that the structure containing a new C-C covalent bond between two moieties in (AN-Py)+ is formed besides the formation of H-bonded structures after AN-Py is ionized by VUV light. In (AN-Py2)+ cluster cations, new C-C or C-N covalent bonds tend to be formed between two Py, with (Py)2+ as the core in the cluster. The results reveal that new covalent bonds are more likely to be formed between two Py species when AN and Py are present in the cationic clusters. These results provide spectroscopic evidence of the formation of new nitrogen-containing organic compounds from AN and Py induced by VUV, which are helpful for our understanding of the formation of diverse prebiotic molecules in interstellar space.
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Affiliation(s)
- Xujian 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
| | - Chengcheng Wei
- 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
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6
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Liang P, de Aragão EVF, Pannacci G, Vanuzzo G, Giustini A, Marchione D, Recio P, Ferlin F, Stranges D, Lago NF, Rosi M, Casavecchia P, Balucani N. Reactions O( 3P, 1D) + HCCCN(X 1Σ +) (Cyanoacetylene): Crossed-Beam and Theoretical Studies and Implications for the Chemistry of Extraterrestrial Environments. J Phys Chem A 2023; 127:685-703. [PMID: 36638186 PMCID: PMC9884085 DOI: 10.1021/acs.jpca.2c07708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cyanoacetylene (HCCCN), the first member of the cyanopolyyne family (HCnN, where n = 3, 5, 7, ...), is of particular interest in astrochemistry being ubiquitous in space (molecular clouds, solar-type protostars, protoplanetary disks, circumstellar envelopes, and external galaxies) and also relatively abundant. It is also abundant in the upper atmosphere of Titan and comets. Since oxygen is the third most abundant element in space, after hydrogen and helium, the reaction O + HCCCN can be of relevance in the chemistry of extraterrestrial environments. Despite that, scarce information exists not only on the reactions of oxygen atoms with cyanoacetylene but with nitriles in general. Here, we report on a combined experimental and theoretical investigation of the reactions of cyanoacetylene with both ground 3P and excited 1D atomic oxygen and provide detailed information on the primary reaction products, their branching fractions (BFs), and the overall reaction mechanisms. More specifically, the reactions of O(3P, 1D) with HCCCN(X1Σ+) have been investigated under single-collision conditions by the crossed molecular beams scattering method with mass spectrometric detection and time-of-flight analysis at the collision energy, Ec, of 31.1 kJ/mol. From product angular and time-of-flight distributions, we have identified the primary reaction products and determined their branching fractions (BFs). Theoretical calculations of the relevant triplet and singlet potential energy surfaces (PESs) were performed to assist the interpretation of the experimental results and clarify the reaction mechanism. Adiabatic statistical calculations of product BFs for the decomposition of the main triplet and singlet intermediates have also been carried out. Merging together the experimental and theoretical results, we conclude that the O(3P) reaction is characterized by a minor adiabatic channel leading to OCCCN (cyanoketyl) + H (experimental BF = 0.10 ± 0.05), while the dominant channel (BF = 0.90 ± 0.05) occurs via intersystem crossing to the underlying singlet PES and leads to formation of 1HCCN (cyanomethylene) + CO. The O(1D) reaction is characterized by the same two channels, with the relative CO/H yield being slightly larger. Considering the recorded reactive signal and the calculated entrance barrier, we estimate that the rate coefficient for reaction O(3P) + HC3N at 300 K is in the 10-12 cm3 molec-1 s-1 range. Our results are expected to be useful to improve astrochemical and photochemical models. In addition, they are also relevant in combustion chemistry, because the thermal decomposition of pyrrolic and pyridinic structures present in fuel-bound nitrogen generates many nitrogen-bearing compounds, including cyanoacetylene.
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Affiliation(s)
- Pengxiao Liang
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Emilia V. F. de Aragão
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy,Master-Tec
srl, Via Sicilia 41, Perugia 06128, Italy
| | - Giacomo Pannacci
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Gianmarco Vanuzzo
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Andrea Giustini
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Demian Marchione
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Pedro Recio
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Francesco Ferlin
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Domenico Stranges
- Dipartimento
di Chimica, Università degli Studi
La Sapienza, Roma 00185, Italy
| | - Noelia Faginas Lago
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Marzio Rosi
- Dipartimento
di Ingegneria Civile e Ambientale, Università
degli Studi di Perugia, Perugia 06123, Italy
| | - Piergiorgio Casavecchia
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy,E-mail:
| | - Nadia Balucani
- Dipartimento
di Chimica, Biologia e Biotecnologie, Università
degli Studi di Perugia, Perugia 06123, Italy,E-mail:
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7
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Saha A, Yi R, Fahrenbach AC, Wang A, Jia TZ. A Physicochemical Consideration of Prebiotic Microenvironments for Self-Assembly and Prebiotic Chemistry. Life (Basel) 2022; 12:1595. [PMID: 36295030 PMCID: PMC9604842 DOI: 10.3390/life12101595] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 10/07/2022] [Accepted: 10/08/2022] [Indexed: 11/06/2022] Open
Abstract
The origin of life on Earth required myriads of chemical and physical processes. These include the formation of the planet and its geological structures, the formation of the first primitive chemicals, reaction, and assembly of these primitive chemicals to form more complex or functional products and assemblies, and finally the formation of the first cells (or protocells) on early Earth, which eventually evolved into modern cells. Each of these processes presumably occurred within specific prebiotic reaction environments, which could have been diverse in physical and chemical properties. While there are resources that describe prebiotically plausible environments or nutrient availability, here, we attempt to aggregate the literature for the various physicochemical properties of different prebiotic reaction microenvironments on early Earth. We introduce a handful of properties that can be quantified through physical or chemical techniques. The values for these physicochemical properties, if they are known, are then presented for each reaction environment, giving the reader a sense of the environmental variability of such properties. Such a resource may be useful for prebiotic chemists to understand the range of conditions in each reaction environment, or to select the medium most applicable for their targeted reaction of interest for exploratory studies.
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Affiliation(s)
- Arpita Saha
- Blue Marble Space Institute of Science, 600 1st Ave, Floor 1, Seattle, WA 98104, USA
- Amity Institute of Applied Sciences, Amity University, Kolkata 700135, India
| | - Ruiqin Yi
- Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Albert C. Fahrenbach
- School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia
- Australian Centre for Astrobiology, UNSW Sydney, Sydney, NSW 2052, Australia
- UNSW RNA Institute, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Anna Wang
- School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia
- Australian Centre for Astrobiology, UNSW Sydney, Sydney, NSW 2052, Australia
- UNSW RNA Institute, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Tony Z. Jia
- Blue Marble Space Institute of Science, 600 1st Ave, Floor 1, Seattle, WA 98104, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
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8
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Pastorek A, Clark VHJ, Yurchenko SN, Ferus M, Civiš S. New physical insights: Formamide discharge decomposition and the role of fragments in the formation of large biomolecules. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 278:121322. [PMID: 35537261 DOI: 10.1016/j.saa.2022.121322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 06/14/2023]
Abstract
In this work we present a time-resolved FTIR spectroscopic study on kinetics of atomic and molecular species, specifically CO, CN radical, N2, HCN and CO2 generated in a glow discharge of formamide-nitrogen-water mixture in a helium buffer gas. Radicals such as NH, CH and OH have been proven to be fundamental stones of subsequent chemical reactions having a crucial role in a prebiotic synthesis of large organic molecules. This work contains three main goals. Firstly, we present our time-resolved spectra of formamide decomposition products and discuss the mechanism of collisional excitations between specific species. Secondly, according to our time resolution, we demonstrate and explain the band shape of CO's first overtone and the energy transfer between excited nitrogen and CO, present in our spectra. Lastly, we present theoretical results for the non-LTE modelling of the spectra using bi-temperature approach and a 1D harmonic Franck-Condon approach for the multi-molecule spectra of the formamide decomposition process in the 1800-5600 cm-1 spectral range.
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Affiliation(s)
- Adam Pastorek
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague 8, Czech Republic; Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 78/7, 11519 Prague 1, Czech Republic
| | - Victoria H J Clark
- Faculty of Mathematics and Physical Sciences, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Sergei N Yurchenko
- Faculty of Mathematics and Physical Sciences, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Martin Ferus
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague 8, Czech Republic
| | - Svatopluk Civiš
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague 8, Czech Republic.
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9
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Vanuzzo G, Marchione D, Mancini L, Liang P, Pannacci G, Recio P, Tan Y, Rosi M, Skouteris D, Casavecchia P, Balucani N. The N( 2D) + CH 2CHCN (Vinyl Cyanide) Reaction: A Combined Crossed Molecular Beam and Theoretical Study and Implications for the Atmosphere of Titan. J Phys Chem A 2022; 126:6110-6123. [PMID: 36053010 PMCID: PMC9483977 DOI: 10.1021/acs.jpca.2c04263] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The reaction of electronically excited nitrogen atoms,
N(2D), with vinyl cyanide, CH2CHCN, has been
investigated
under single-collision conditions by the crossed molecular beam (CMB)
scattering method with mass spectrometric detection and time-of-flight
(TOF) analysis at the collision energy, Ec, of 31.4 kJ/mol. Synergistic electronic structure calculations of
the doublet potential energy surface (PES) have been performed to
assist in the interpretation of the experimental results and characterize
the overall reaction micromechanism. Statistical (Rice–Ramsperger–Kassel–Marcus,
RRKM) calculations of product branching fractions (BFs) on the theoretical
PES have been carried out at different values of temperature, including
the one corresponding to the temperature (175 K) of Titan’s
stratosphere and at a total energy corresponding to the Ec of the CMB experiment. According to our theoretical
calculations, the reaction is found to proceed via barrierless addition
of N(2D) to the carbon–carbon double bond of CH2=CH–CN, followed by the formation of cyclic
and linear intermediates that can undergo H, CN, and HCN elimination.
In competition, the N(2D) addition to the CN group is also
possible via a submerged barrier, leading ultimately to N2 + C3H3 formation, the most exothermic of all
possible channels. Product angular and TOF distributions have been
recorded for the H-displacement channels leading to the formation
of a variety of possible C3H2N2 isomeric
products. Experimentally, no evidence of CN, HCN, and N2 forming channels was observed. These findings were corroborated
by the theory, which predicts a variety of competing product channels,
following N(2D) addition to the double bond, with the main
ones, at Ec = 31.4 kJ/mol, being six isomeric
H forming channels: c-CH(N)CHCN + H (BF = 35.0%), c-CHNCHCN + H (BF = 28.1%), CH2NCCN + H (BF =
26.3%), c-CH2(N)CCN(cyano-azirine) + H
(BF = 7.4%), trans-HNCCHCN + H (BF = 1.6%), and cis-HNCCHCN + H (BF = 1.3%), while C–C bond breaking
channels leading to c-CH2(N)CH(2H-azirine)
+ CN and c-CH2(N)C + HCN are predicted
to be negligible (0.02% and 0.2%, respectively). The highly exothermic
N2 + CH2CCH (propargyl) channel is also predicted
to be negligible because of the very high isomerization barrier from
the initial addition intermediate to the precursor intermediate able
to lead to products. The predicted product BFs are found to have,
in general, a very weak energy dependence. The above cyclic and linear
products containing an additional C–N bond could be potential
precursors of more complex, N-rich organic molecules that contribute
to the formation of the aerosols on Titan’s upper atmosphere.
Overall, the results are expected to have a significant impact on
the gas-phase chemistry of Titan’s atmosphere and should be
properly included in the photochemical models.
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Affiliation(s)
- Gianmarco Vanuzzo
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Demian Marchione
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Luca Mancini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Pengxiao Liang
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Giacomo Pannacci
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Pedro Recio
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Yuxin Tan
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Marzio Rosi
- Dipartimento di Ingegneria Civile e Ambientale, Università degli Studi di Perugia, 06125 Perugia, Italy
| | | | - Piergiorgio Casavecchia
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Nadia Balucani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
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10
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Cheng X, Li F, Zhao Y, Cheng X, Nie K, Han Y, Yang Y. Stability, atomic charges, bond order analysis, and the directionality of lone‐electron pairs on nitriles and isocyanides. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xueli Cheng
- School of Chemistry and Chemical Engineering, Taishan University Tai’an China
| | - Feng Li
- Department of Teaching Affairs Taishan University Tai’an China
| | - Yanyun Zhao
- School of Chemistry and Chemical Engineering, Taishan University Tai’an China
| | - Xiaoyu Cheng
- School of Chemistry, Chemical Engineering and Materials Science Shandong Normal University Jinan China
| | - Kun Nie
- School of Chemistry and Chemical Engineering, Taishan University Tai’an China
| | - Yinfeng Han
- School of Chemistry and Chemical Engineering, Taishan University Tai’an China
| | - Yongjuan Yang
- School of Chemistry and Chemical Engineering, Taishan University Tai’an China
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11
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Marchione D, Mancini L, Liang P, Vanuzzo G, Pirani F, Skouteris D, Rosi M, Casavecchia P, Balucani N. Unsaturated Dinitriles Formation Routes in Extraterrestrial Environments: A Combined Experimental and Theoretical Investigation of the Reaction between Cyano Radicals and Cyanoethene (C 2H 3CN). J Phys Chem A 2022; 126:3569-3582. [PMID: 35640168 PMCID: PMC9189926 DOI: 10.1021/acs.jpca.2c01802] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The reaction between
cyano radicals (CN, X2Σ+) and cyanoethene
(C2H3CN) has been
investigated by a combined approach coupling crossed molecular beam
(CMB) experiments with mass spectrometric detection and time-of-flight
analysis at a collision energy of 44.6 kJ mol–1 and
electronic structure calculations to determine the relevant potential
energy surface. The experimental results can be interpreted by assuming
the occurrence of a dominant reaction pathway leading to the two but-2-enedinitrile
(1,2-dicyanothene) isomers (E- and Z-NC–CH=CH–CN) in a H-displacement channel and,
to a much minor extent, to 1,1-dicyanoethene, CH2C(CN)2. In order to derive the product branching ratios under the
conditions of the CMB experiments and at colder temperatures, including
those relevant to Titan and to cold interstellar clouds, we have carried
out RRKM statistical calculations using the relevant potential energy
surface of the investigated reaction. We have also estimated the rate
coefficient at very low temperatures by employing a semiempirical
method for the treatment of long-range interactions. The reaction
has been found to be barrierless and fast also under the low temperature
conditions of cold interstellar clouds and the atmosphere of Titan.
Astrophysical implications and comparison with literature data are
also presented. On the basis of the present work, 1,2-dicyanothene
and 1,1-dicyanothene are excellent candidates for the search of dinitriles
in the interstellar medium.
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Affiliation(s)
- Demian Marchione
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Luca Mancini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Pengxiao Liang
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Gianmarco Vanuzzo
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | | | - Marzio Rosi
- Dipartimento di Ingegneria Civile ed Ambientale, Università degli Studi di Perugia, 06125 Perugia, Italy
| | - Piergiorgio Casavecchia
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Nadia Balucani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
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12
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Barnum TJ, Siebert MA, Lee KLK, Loomis RA, Changala PB, Charnley SB, Sita ML, Xue C, Remijan AJ, Burkhardt AM, McGuire BA, Cooke IR. A Search for Heterocycles in GOTHAM Observations of TMC-1. J Phys Chem A 2022; 126:2716-2728. [PMID: 35442689 DOI: 10.1021/acs.jpca.2c01435] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have conducted an extensive search for nitrogen-, oxygen-, and sulfur-bearing heterocycles toward Taurus Molecular Cloud 1 (TMC-1) using the deep, broadband centimeter-wavelength spectral line survey of the region from the GOTHAM large project on the Green Bank Telescope. Despite their ubiquity in terrestrial chemistry, and the confirmed presence of a number of cyclic and polycyclic hydrocarbon species in the source, we find no evidence for the presence of any heterocyclic species. Here, we report the derived upper limits on the column densities of these molecules obtained by Markov Chain Monte Carlo (MCMC) analysis and compare this approach to traditional single-line upper limit measurements. We further hypothesize why these molecules are absent in our data, how they might form in interstellar space, and the nature of observations that would be needed to secure their detection.
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Affiliation(s)
- Timothy J Barnum
- Department of Chemistry, Union College, Schenectady, New York 12308, United States
| | - Mark A Siebert
- Department of Astronomy, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Kin Long Kelvin Lee
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ryan A Loomis
- National Radio Astronomy Observatory, Charlottesville, Virginia 22903, United States
| | - P Bryan Changala
- Center for Astrophysics
- Harvard & Smithsonian, Cambridge, Massachusetts 02138, United States
| | - Steven B Charnley
- Astrochemistry Laboratory and the Goddard Center for Astrobiology, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, United States
| | - Madelyn L Sita
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Ci Xue
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Anthony J Remijan
- National Radio Astronomy Observatory, Charlottesville, Virginia 22903, United States
| | - Andrew M Burkhardt
- Department of Physics, Wellesley College, 106 Central Street, Wellesley, Massachusetts 02481, United States
| | - Brett A McGuire
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.,National Radio Astronomy Observatory, Charlottesville, Virginia 22903, United States.,Center for Astrophysics
- Harvard & Smithsonian, Cambridge, Massachusetts 02138, United States
| | - Ilsa R Cooke
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
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13
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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.
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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.
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14
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Mancini L, Vanuzzo G, Marchione D, Pannacci G, Liang P, Recio P, Rosi M, Skouteris D, Casavecchia P, Balucani N. The Reaction N( 2D) + CH 3CCH (Methylacetylene): A Combined Crossed Molecular Beams and Theoretical Investigation and Implications for the Atmosphere of Titan. J Phys Chem A 2021; 125:8846-8859. [PMID: 34609869 PMCID: PMC8521525 DOI: 10.1021/acs.jpca.1c06537] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The reaction of excited
nitrogen atoms N(2D) with CH3CCH (methylacetylene)
was investigated under single-collision
conditions by the crossed molecular beams (CMB) scattering method
with mass spectrometric detection and time-of-flight analysis at the
collision energy (Ec) of 31.0 kJ/mol.
Synergistic electronic structure calculations of the doublet potential
energy surface (PES) were performed to assist the interpretation of
the experimental results and characterize the overall reaction micromechanism.
Theoretically, the reaction is found to proceed via a barrierless addition of N(2D) to the carbon–carbon
triple bond of CH3CCH and an insertion of N(2D) into the CH bond of the methyl group, followed
by the formation of cyclic and linear intermediates that can undergo
H, CH3, and C2H elimination or isomerize to
other intermediates before unimolecularly decaying to a variety of
products. Kinetic calculations for addition and insertion mechanisms
and statistical (Rice-Ramsperger-Kassel-Marcus) computations of product
branching fractions (BFs) on the theoretical PES were performed at
different values of total energy, including the one corresponding
to the temperature (175 K) of Titan’s stratosphere and that
of the CMB experiment. Up to 14 competing product channels were statistically
predicted, with the main ones, at Ec =
31.0 kJ/mol, being the formation of CH2NH (methanimine)
+ C2H (ethylidyne) (BF = 0.41), c-C(N)CH
+ CH3 (BF = 0.32), CH2CHCN (acrylonitrile) +
H (BF = 0.12), and c-CH2C(N)CH + H (BF
= 0.04). Of the 14 possible channels, seven correspond to H displacement
channels of different exothermicity, for a total H channel BF of ∼0.25
at Ec = 31.0 kJ/mol. Experimentally, dynamical
information could only be obtained about the overall H channels. In
particular, the experiment corroborates the formation of acrylonitrile
+ H, which is the most exothermic of all 14 reaction channels and
is theoretically calculated to be the dominant H-forming channel (BF
= 0.12). The products containing a novel C–N bond could be
potential precursors to form other nitriles (C2N2, C3N) or more complex organic species containing N atoms
in planetary atmospheres, such as those of Titan and Pluto. Overall,
the results are expected to have a potentially significant impact
on the understanding of the gas-phase chemistry of Titan’s
atmosphere and the modeling of that atmosphere.
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Affiliation(s)
- Luca Mancini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Gianmarco Vanuzzo
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Demian Marchione
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Giacomo Pannacci
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Pengxiao Liang
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Pedro Recio
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Marzio Rosi
- Dipartimento di Ingegneria Civile e Ambientale, Università degli Studi di Perugia, 06125 Perugia, Italy
| | | | - Piergiorgio Casavecchia
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Nadia Balucani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
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15
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Liang P, Mancini L, Marchione D, Vanuzzo G, Ferlin F, Recio P, Tan Y, Pannacci G, Vaccaro L, Rosi M, Casavecchia P, Balucani N. Combined crossed molecular beams and computational study on the N( 2D) + HCCCN(X 1Σ +) reaction and implications for extra-terrestrial environments. Mol Phys 2021. [DOI: 10.1080/00268976.2021.1948126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Pengxiao Liang
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Luca Mancini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Demian Marchione
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Gianmarco Vanuzzo
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Francesco Ferlin
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Pedro Recio
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Yuxin Tan
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
- ERASMUS+ Visiting Ph.D. student from Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei, People’s Republic of China
| | - Giacomo Pannacci
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Luigi Vaccaro
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Marzio Rosi
- Dipartimento di Ingegneria Civile e Ambientale, Università degli Studi di Perugia, Perugia, Italy
| | - Piergiorgio Casavecchia
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Nadia Balucani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
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16
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Micca Longo G, Vialetto L, Diomede P, Longo S, Laporta V. Plasma Modeling and Prebiotic Chemistry: A Review of the State-of-the-Art and Perspectives. Molecules 2021; 26:molecules26123663. [PMID: 34208472 PMCID: PMC8235047 DOI: 10.3390/molecules26123663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/08/2021] [Accepted: 06/09/2021] [Indexed: 11/20/2022] Open
Abstract
We review the recent progress in the modeling of plasmas or ionized gases, with compositions compatible with that of primordial atmospheres. The plasma kinetics involves elementary processes by which free electrons ultimately activate weakly reactive molecules, such as carbon dioxide or methane, thereby potentially starting prebiotic reaction chains. These processes include electron–molecule reactions and energy exchanges between molecules. They are basic processes, for example, in the famous Miller-Urey experiment, and become relevant in any prebiotic scenario where the primordial atmosphere is significantly ionized by electrical activity, photoionization or meteor phenomena. The kinetics of plasma displays remarkable complexity due to the non-equilibrium features of the energy distributions involved. In particular, we argue that two concepts developed by the plasma modeling community, the electron velocity distribution function and the vibrational distribution function, may unlock much new information and provide insight into prebiotic processes initiated by electron–molecule collisions.
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Affiliation(s)
- Gaia Micca Longo
- Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via Edoardo Orabona 4, 70126 Bari, Italy;
| | - Luca Vialetto
- Center for Computational Energy Research, DIFFER—Dutch Institute for Fundamental Energy Research, De Zaale 20, 5612 AJ Eindhoven, The Netherlands;
| | - Paola Diomede
- Faculty of Science and Engineering, Maastricht University, Paul Henri Spaaklaan 1, 6229 GS Maastricht, The Netherlands;
| | - Savino Longo
- Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via Edoardo Orabona 4, 70126 Bari, Italy;
- Istituto per la Scienza e Tecnologia dei Plasmi, CNR, Via Amendola, 122/D, 70126 Bari, Italy;
- Correspondence: ; Tel.: +39-0805442088
| | - Vincenzo Laporta
- Istituto per la Scienza e Tecnologia dei Plasmi, CNR, Via Amendola, 122/D, 70126 Bari, Italy;
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17
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Abstract
Machine learning (ML) techniques applied to chemical reactions have a long history. The present contribution discusses applications ranging from small molecule reaction dynamics to computational platforms for reaction planning. ML-based techniques can be particularly relevant for problems involving both computation and experiments. For one, Bayesian inference is a powerful approach to develop models consistent with knowledge from experiments. Second, ML-based methods can also be used to handle problems that are formally intractable using conventional approaches, such as exhaustive characterization of state-to-state information in reactive collisions. Finally, the explicit simulation of reactive networks as they occur in combustion has become possible using machine-learned neural network potentials. This review provides an overview of the questions that can and have been addressed using machine learning techniques, and an outlook discusses challenges in this diverse and stimulating field. It is concluded that ML applied to chemistry problems as practiced and conceived today has the potential to transform the way with which the field approaches problems involving chemical reactions, in both research and academic teaching.
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Affiliation(s)
- Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland.,Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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18
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Sun F, Xie M, Zhang Y, Song W, Sun X, Hu Y. Spectroscopic evidence of the C-N covalent bond formed between two interstellar molecules (ISM): acrylonitrile and ammonia. Phys Chem Chem Phys 2021; 23:9672-9678. [PMID: 33616131 DOI: 10.1039/d0cp06274j] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Acrylonitrile (AN) and ammonia (NH3) are two important nitrogen-containing interstellar molecules in outer space, especially on Titan. Herein, we measured infrared (IR) spectra of neutral and cationic AN-NH3 complexes by VUV single-photon ionization combined with time-of-flight mass spectrometry. On combining IR spectra with the theoretical calculations, we found that the molecules prefer to form a single-ring cyclic H-bonded structure in the neutral AN-NH3 and (AN)2-NH3 clusters. However, after ionization of AN-NH3 and (AN)2-NH3 clusters, a new C-N-covalent bond is confirmed to form directly between AN and NH3, without any energy barrier in the cationic complexes. Moreover, in the ionized (AN)2-NH3 cluster, the covalent C-N bond prefers to form between AN and NH3 rather than the two AN groups. These results provide spectroscopic evidence of AN forming a new molecule with NH3, induced by VUV radiation. The formation of the new C-N bond broadens our knowledge on the evolution of the prebiotic nitrogen-containing molecules in space.
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Affiliation(s)
- Fufei Sun
- 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.
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19
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Pastorek A, Ferus M, Čuba V, Šrámek O, Ivanek O, Civiš S. Primordial Radioactivity and Prebiotic Chemical Evolution: Effect of γ Radiation on Formamide-Based Synthesis. J Phys Chem B 2020; 124:8951-8959. [PMID: 32970439 DOI: 10.1021/acs.jpcb.0c05233] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although the effect of ionizing radiation on prebiotic chemistry is often overlooked, primordial natural radioactivity might have been an important source of energy for various chemical transformations. Estimates of the abundances of short-lived radionuclides on early Earth suggest that the primordial intensity of endogenous terrestrial radioactivity was up to 4 × 103 times higher than it is today. Therefore, we assume that chemical substances in contact with radioactive rocks should therefore undergo radiolysis. The calculations are followed by research investigating the influence of ionizing γ radiation on basic prebiotic substances, including formamide mixed with various clays, which might have played the role of a catalyst and an agent that partially blocked radiation that was potentially destructive for the products. Our explorations of this effect have shown that the irradiation of formamide-clay mixtures at doses of ∼6 kGy produces significant amounts of urea (up to the maximal concentration of approximately 250 mg L-1), which plays a role in HCN-based prebiotic chemistry.
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Affiliation(s)
- Adam Pastorek
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague, Prague 8, Czech Republic.,Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 78/7, 11519 Prague, Prague 1, Czech Republic
| | - Martin Ferus
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague, Prague 8, Czech Republic
| | - Václav Čuba
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 78/7, 11519 Prague, Prague 1, Czech Republic
| | - Ondřej Šrámek
- Department of Geophysics, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 18000 Prague, Prague 8, Czech Republic
| | - Ondřej Ivanek
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague, Prague 8, Czech Republic
| | - Svatopluk Civiš
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague, Prague 8, Czech Republic
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20
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Pérez-Villa A, Pietrucci F, Saitta AM. Reply to comments on "Prebiotic chemistry and origins of life research with atomistic computer simulations". Phys Life Rev 2020; 34-35:153-155. [PMID: 32482440 DOI: 10.1016/j.plrev.2020.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 11/17/2022]
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21
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Zareipour R, Vahedpour M. Ground state potential energy surface of methanimine plus 3NH reaction: Rates of atmospheric reactions and validated mechanisms. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Zhang Z, Nie W, Sun F, Zhang Y, Xie M, Hu Y. Conformational Landscapes and Infrared Spectra of Gas-phase Interstellar Molecular Clusters [(C 3H 3N)(CH 3OH) n, n = 1-4]. J Phys Chem A 2020; 124:2398-2407. [PMID: 32149507 DOI: 10.1021/acs.jpca.9b11387] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acrylonitrile (A) is one of the important interstellar molecules, which is considered closely related to the origin of life. And methanol (M) is one of the commonly used solvents, which is also found in outer space. Herein, we obtained the infrared (IR) spectra of size-selected AMn (n = 1-4) clusters in supersonic jet by monitoring their fragments of H+AMn-1 (n = 1-4) with vacuum ultraviolet single-photon soft ionization/IR-depletion technique. IR spectra of AMn (n = 1-4) clusters were recorded in the CH and OH vibration bands in the range of 2700-3800 cm-1. Spectra of AMn (n = 1-4) clusters are similar in the CH stretching regions, while those show significant variations in the OH stretching regions with the increase of methanol molecules. Calculated IR spectra, which were predicted with the B3LYP-D3(BJ)/aug-cc-pVDZ method, were employed to compare with the experimental results. For AM, AM2, and AM3, the structures with the methanol cyclic hydrogen bonded with [N1-C4(H6)] of acrylonitrile are more stable than the other H-bonded structures. For the most stable structures of AM4, however, the results show that the acrylonitrile is binding to a H-bonded ring formed by OH groups of four methanol molecules. The AM, AM2, and AM3 conformers with the single ring on the C1 side of acrylonitrile, such as C1-AM-a, C1-AM2-a, and C1-AM3-a, are dominant in the gas phase, while the C2-AM4-a conformer with the H-bonded ring formed by the OH groups on the C2 side of acrylonitrile is more stable than that of CM4-A-a in our experimental conditions (>130 K). These findings may provide valuable insight into the microsolvation process of the interstellar molecules and other biomolecules in gas phase.
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Affiliation(s)
- Zhaoli Zhang
- MOE & Guangdong Province Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
| | - Wuyi Nie
- MOE & Guangdong Province Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
| | - Fufei Sun
- MOE & Guangdong Province Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
| | - Yu Zhang
- MOE & Guangdong Province Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
| | - Min Xie
- MOE & Guangdong Province Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
| | - Yongjun Hu
- MOE & Guangdong Province Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
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Keshavarz F. Chemical Kinetics Approves the Occurrence of C ( 3P j) Reaction with H 2O. J Phys Chem A 2019; 123:5877-5892. [PMID: 31268710 DOI: 10.1021/acs.jpca.9b03492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although both atomic carbon and water are omnipresent in human life, there is a debate about the possibility of carbon reaction with water. Some low-temperature spectroscopic investigations have rejected the reaction, whereas some room-temperature experiments and theoretical studies have accepted the possibility of the reaction by reporting rate coefficients ranging from 105 to 109 L mol-1 s-1. This study provides new lines of evidence about the reaction through exploration of the reaction mechanism using the CCSD(T) method and solving the corresponding master equation by following two main approaches. According to the results, the rate coefficient of the reaction is significantly influenced by the tunneling and hindered rotation effects, in addition to the selected total angular momentum (J). Furthermore, the total rate coefficient of the reaction increases dramatically (from 107 to 1011 L mol-1 s-1) with the rise of temperature from 100 to 4000 K, while the total rate coefficient is insensitive to pressure (0.1-10 atm). Despite some differences between the results of the two approaches, the rate coefficients of both methods are consistent with the previously reported rate coefficients. Also, in agreement with the previous studies, the major products are 2HOC + 2H and 2HCO + 2H. In general, the findings approve the occurrence of the title reaction and indicate that the mentioned conflict is due to the sensitivity of the reaction to the investigated temperature and J level. The sensitivity does not permit low-temperature spectroscopic studies to detect any products and varies the measured and calculated rate coefficients.
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Affiliation(s)
- Fatemeh Keshavarz
- Department of Chemistry, College of Science , Shiraz University , Shiraz 71946-84795 , Iran
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24
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A Modern-Fortran Program for Chemical Kinetics on Top of Anharmonic Vibrational Calculations. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/978-3-030-24311-1_29] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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25
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Nitrogen heterocycles form peptide nucleic acid precursors in complex prebiotic mixtures. Sci Rep 2019; 9:9281. [PMID: 31243303 PMCID: PMC6594999 DOI: 10.1038/s41598-019-45310-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/29/2019] [Indexed: 11/29/2022] Open
Abstract
The ability to store information is believed to have been crucial for the origin and evolution of life; however, little is known about the genetic polymers relevant to abiogenesis. Nitrogen heterocycles (N-heterocycles) are plausible components of such polymers as they may have been readily available on early Earth and are the means by which the extant genetic macromolecules RNA and DNA store information. Here, we report the reactivity of numerous N-heterocycles in highly complex mixtures, which were generated using a Miller-Urey spark discharge apparatus with either a reducing or neutral atmosphere, to investigate how N-heterocycles are modified under plausible prebiotic conditions. High throughput mass spectrometry was used to identify N-heterocycle adducts. Additionally, tandem mass spectrometry and nuclear magnetic resonance spectroscopy were used to elucidate reaction pathways for select reactions. Remarkably, we found that the majority of N-heterocycles, including the canonical nucleobases, gain short carbonyl side chains in our complex mixtures via a Strecker-like synthesis or Michael addition. These types of N-heterocycle adducts are subunits of the proposed RNA precursor, peptide nucleic acids (PNAs). The ease with which these carbonylated heterocycles form under both reducing and neutral atmospheres is suggestive that PNAs could be prebiotically feasible on early Earth.
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26
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Balucani N. An atomistic approach to prebiotic chemistry: A tool to overcome the limits of laboratory simulations: Comment on "Prebiotic chemistry and origins of life research with atomistic computer simulations". Phys Life Rev 2019; 34-35:136-138. [PMID: 30905552 DOI: 10.1016/j.plrev.2019.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 03/13/2019] [Indexed: 11/26/2022]
Affiliation(s)
- Nadia Balucani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy.
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Rivilla VM, Martín-Pintado J, Jiménez-Serra I, Zeng S, Martín S, Armijos-Abendaño J, Requena-Torres MA, Aladro R, Riquelme D. Abundant Z-cyanomethanimine in the interstellar medium: paving the way to the synthesis of adenine. ACTA ACUST UNITED AC 2018. [DOI: 10.1093/mnrasl/sly228] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- V M Rivilla
- INAF-Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125, Florence, Italy
| | - J Martín-Pintado
- Centro de Astrobiología (CSIC−INTA). Ctra de Ajalvir, km. 4, Torrejón de Ardoz, E-28850 Madrid, Spain
| | - I Jiménez-Serra
- Centro de Astrobiología (CSIC−INTA). Ctra de Ajalvir, km. 4, Torrejón de Ardoz, E-28850 Madrid, Spain
| | - S Zeng
- School of Physics and Astronomy, Queen Mary University of London, Mile End Road, E1 4NS London, United Kingdom
| | - S Martín
- European Southern Observatory (ESO), Alonso de Córdova 3107, Vitacura, 763 0355 Santiago, Chile
- Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura, Santiago, Chile
| | - J Armijos-Abendaño
- Observatorio Astronómico de Quito, Escuela Politécnica Nacional, Av. Gran Colombia S/N, Interior del Parque La Alameda, 170136 Quito, Ecuador
| | - M A Requena-Torres
- Department of Astronomy, University of Maryland, College Park, ND 20742-2421, USA
| | - R Aladro
- Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany
| | - D Riquelme
- Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany
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28
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Turner AM, Bergantini A, Abplanalp MJ, Zhu C, Góbi S, Sun BJ, Chao KH, Chang AHH, Meinert C, Kaiser RI. An interstellar synthesis of phosphorus oxoacids. Nat Commun 2018; 9:3851. [PMID: 30242164 PMCID: PMC6155066 DOI: 10.1038/s41467-018-06415-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Accepted: 08/29/2018] [Indexed: 11/09/2022] Open
Abstract
Phosphorus signifies an essential element in molecular biology, yet given the limited solubility of phosphates on early Earth, alternative sources like meteoritic phosphides have been proposed to incorporate phosphorus into biomolecules under prebiotic terrestrial conditions. Here, we report on a previously overlooked source of prebiotic phosphorus from interstellar phosphine (PH3) that produces key phosphorus oxoacids-phosphoric acid (H3PO4), phosphonic acid (H3PO3), and pyrophosphoric acid (H4P2O7)-in interstellar analog ices exposed to ionizing radiation at temperatures as low as 5 K. Since the processed material of molecular clouds eventually enters circumstellar disks and is partially incorporated into planetesimals like proto Earth, an understanding of the facile synthesis of oxoacids is essential to untangle the origin of water-soluble prebiotic phosphorus compounds and how they might have been incorporated into organisms not only on Earth, but potentially in our universe as well.
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Affiliation(s)
- Andrew M Turner
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
| | - Alexandre Bergantini
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
| | - Matthew J Abplanalp
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
| | - Cheng Zhu
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
| | - Sándor Góbi
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA
| | - Bing-Jian Sun
- Department of Chemistry, National Dong Hwa University, Shoufeng, 974, Hualien, Taiwan
| | - Kang-Heng Chao
- Department of Chemistry, National Dong Hwa University, Shoufeng, 974, Hualien, Taiwan
| | - Agnes H H Chang
- Department of Chemistry, National Dong Hwa University, Shoufeng, 974, Hualien, Taiwan
| | - Cornelia Meinert
- Université Côte d'Azur, CNRS, Institut de Chimie de Nice, Nice, France
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA.
- W.M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI, 96822, USA.
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de Ruette N, Wolf M, Giacomozzi L, Alexander JD, Gatchell M, Stockett MH, Haag N, Zettergren H, Schmidt HT, Cederquist H. DESIREE electrospray ion source test bench and setup for collision induced dissociation experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:075102. [PMID: 30068131 DOI: 10.1063/1.5030528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this paper, we give a detailed description of an electrospray ion source test bench and a single-pass setup for ion fragmentation studies at the Double ElectroStatic Ion Ring ExpEriment infrastructure at Stockholm University. This arrangement allows for collision-induced dissociation experiments at the center-of-mass energies between 10 eV and 1 keV. Charged fragments are analyzed with respect to their kinetic energies (masses) by means of an electrostatic energy analyzer with a wide angular acceptance and adjustable energy resolution.
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Affiliation(s)
- N de Ruette
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - M Wolf
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - L Giacomozzi
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - J D Alexander
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - M Gatchell
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - M H Stockett
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - N Haag
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - H Zettergren
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - H T Schmidt
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
| | - H Cederquist
- Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden
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Sleiman C, El Dib G, Rosi M, Skouteris D, Balucani N, Canosa A. Low temperature kinetics and theoretical studies of the reaction CN + CH 3NH 2: a potential source of cyanamide and methyl cyanamide in the interstellar medium. Phys Chem Chem Phys 2018; 20:5478-5489. [PMID: 29082409 DOI: 10.1039/c7cp05746f] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between cyano radicals (which are ubiquitous in interstellar clouds) and methylamine (a molecule detected in various interstellar sources) has been investigated in a synergistic experimental and theoretical study. The reaction has been found to be very fast in the entire range of temperatures investigated (23-297 K) by using a CRESU apparatus coupled to pulsed laser photolysis - laser induced fluorescence. The global experimental rate coefficient is given by In addition, dedicated electronic structure calculations of the underlying potential energy surface have been performed, together with capture theory and RRKM calculations. The experimental data have been interpreted in the light of the theoretical calculations and the product branching ratio has been established. According to the present study, in the range of temperatures investigated the title reaction is an efficient interstellar route of formation of cyanamide, NH2CN, another interstellar species. The second most important channel is the one leading to methyl cyanamide, CH3NHCN (an isomer of aminoacetonitrile), via a CN/H exchange mechanism with a yield of 12% of the global reaction in the entire range of temperatures explored. For a possible inclusion in future astrochemical models we suggest, by referring to the usual expression the following values: α = 3.68 × 10-12 cm3 molec-1 s-1, β = -1.80, γ = 7.79 K for the channel leading to NH2CN + CH3; α = 5.05 × 10-13 cm3 molec-1 s-1, β = -1.82, γ = 7.93 K for the channel leading to CH3NHCN + H.
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Affiliation(s)
- Chantal Sleiman
- Institut de Physique de Rennes, UMR 6251 du CNRS - Université de Rennes 1, Bat. 11C, Campus de Beaulieu, 263 Avenue du Général Leclerc, F-35042 Rennes Cedex, France.
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31
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Melosso M, Melli A, Puzzarini C, Codella C, Spada L, Dore L, Degli Esposti C, Lefloch B, Bachiller R, Ceccarelli C, Cernicharo J, Barone V. Laboratory measurements and astronomical search for cyanomethanimine. ASTRONOMY AND ASTROPHYSICS 2018; 609:A121. [PMID: 30078846 PMCID: PMC6071866 DOI: 10.1051/0004-6361/201731972] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
CONTEXT C-cyanomethanimine (HNCHCN), existing in the two Z and E isomeric forms, is a key prebiotic molecule, but, so far, only the E isomer has been detected toward the massive star-forming region. Sagittarius B2(N) using transitions in the radio wavelength domain. AIMS With the aim of detecting HNCHCN in Sun-like-star forming regions, the laboratory investigation of its rotational spectrum has been extended to the millimeter-/submillimeter-wave (mm-/submm-) spectral window in which several unbiased spectral surveys have been already carried out. METHODS High-resolution laboratory measurements of the rotational spectrum of C-cyanomethanimine were carried out in the 100-420 GHz range using a frequency-modulation absorption spectrometer. We then searched for the C-cyanomethanimine spectral features in the mm-wave range using the high-sensitivity and unbiased spectral surveys obtained with the IRAM 30-m antenna in the ASAI context, the earliest stages of star formation from starless to evolved Class I objects being sampled. RESULTS For both the Z and E isomers, the spectroscopic work has led to an improved and extended knowledge of the spectroscopic parameters, thus providing accurate predictions of the rotational signatures up to ~700 GHz. So far, no C-cyanomethanimine emission has been detected toward the ASAI targets, and upper limits of the column density of ~ 1011-1012 cm-2 could only be derived. Consequently, the C-cyanomethanimine abundances have to be less than a few 10-10 for starless and hot-corinos. A less stringent constraint, ≤ 10-9, is obtained for shocks sites. CONCLUSIONS The combination of the upper limits of the abundances of C-cyanomethanimine together with accurate laboratory frequencies up to ~ 700 GHz poses the basis for future higher sensitivity searches around Sun-like-star forming regions. For compact (typically less than 1″) and chemically enriched sources such as hot-corinos, the use of interferometers as NOEMA and ALMA in their extended configurations are clearly needed.
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Affiliation(s)
- M. Melosso
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
| | - A. Melli
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
| | - C. Puzzarini
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
- INAF, Osservatorio Astonomico di Arcetri, Largo E. Fermi 5, 50125, Firenze, Italy
| | - C. Codella
- INAF, Osservatorio Astonomico di Arcetri, Largo E. Fermi 5, 50125, Firenze, Italy
| | - L. Spada
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy
| | - L. Dore
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
| | - C. Degli Esposti
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
| | - B. Lefloch
- Univ. Grenoble Alpes, CNRS, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG), 38000 Grenoble, France
| | - R. Bachiller
- IGN, Observatorio Astronómico Nacional, Calle Alfonso XII, 28004 Madrid, Spain
| | - C. Ceccarelli
- INAF, Osservatorio Astonomico di Arcetri, Largo E. Fermi 5, 50125, Firenze, Italy
- Univ. Grenoble Alpes, CNRS, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG), 38000 Grenoble, France
| | - J. Cernicharo
- Grupo de Astrofísica Molecular. Instituto de CC. de Materiales de Madrid (ICMM-CSIC). Sor Juana Inés de la Cruz 3, Cantoblanco, 28049 Madrid, Spain
| | - V. Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy
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Gamez-Garcia VG, Galano A. Systematic Search for Chemical Reactions in Gas Phase Contributing to Methanol Formation in Interstellar Space. J Phys Chem A 2017; 121:7393-7400. [PMID: 28885025 DOI: 10.1021/acs.jpca.7b05797] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A massive search for chemical routes leading to methanol formation in gas phase has been conducted using computational chemistry, at the CBS-QB3 level of theory. The calculations were performed at five different temperatures (100, 80, 50, 20, and 10 K) and at three pressures (0.1, 0.01, and 0.001 atm) for each temperature. The search was focused on identifying reactions with the necessary features to be viable in the interstellar medium (ISM). A searching strategy was applied to that purpose, which allowed to reduce an initial set of 678 possible reactions to a subset of 11 chemical routes that are recommended, for the first time, as potential candidates for contributing to methanol formation in the gas phase of the ISM. They are all barrier-less, and thus they are expected to take place at collision rates. Hopefully, including these reactions in the currently available models, for the gas-phase methanol formation in the ISM, would help improving the predicted fractional abundance of this molecule in dark clouds. Further investigations, especially those dealing with grain chemistry and electronic excited states, would be crucial to get a complete picture of the methanol formation in the ISM.
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Affiliation(s)
- Victoria G Gamez-Garcia
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa , San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, C. P. 09340, México D. F. México
| | - Annia Galano
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa , San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, C. P. 09340, México D. F. México
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Banerjee S, Skouteris D, Barone V. A diabatic electronic state system to describe the internal conversion of azulene. COMPUTATIONAL SCIENCE AND ITS APPLICATIONS : ICCSA ... : INTERNATIONAL CONFERENCE ... PROCEEDINGS. ICCSA (CONFERENCE) 2017; 10408:328-337. [PMID: 31032486 PMCID: PMC6485616 DOI: 10.1007/978-3-319-62404-4_24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A diabatic system of two electronic potential energy surfaces as well as the coupling between them is presented. The system is to be used to study the dynamics of the S1 → S0 internal conversion of azulene and is based on single point calculations of the minima of the two surfaces and a dipole-quadrupole (DQ) diabatization. Based on this, a couple of harmonic diabatic surfaces together with a linear coupling surface have been devised. Some preliminary dynamics results are shown.
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Ranka K, Perera A, Bartlett RJ. Elementary reaction profile and chemical kinetics study of [C(1D)/(3P) + SiH4] with the CCSD(T) method. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.05.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Penocchio E, Mendolicchio M, Tasinato N, Barone V. Structural features of the carbon-sulfur chemical bond: a semi-experimental perspective. CAN J CHEM 2016; 94:1065-1076. [PMID: 28912608 PMCID: PMC5595238 DOI: 10.1139/cjc-2016-0282] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this work semi-experimental and theoretical equilibrium geometries of 10 sulfur-containing organic molecules, as well as 4 oxygenated ones, are determined by means of a computational protocol based on density functional theory. The results collected in the present paper further enhance our online database of accurate semi-experimental equilibrium molecular geometries, adding 13 new molecules containing up to 8 atoms, for 12 of which the first semi-experimental equilibrium structure is reported, to the best of our knowledge. We focus in particular on sulfur-containing compounds, aiming both to provide new accurate data on some rather important chemical moieties, only marginally represented in the literature of the field, and to examine the structural features of carbon-sulfur bonds in the light of the previously presented linear regression approach. The structural changes issuing from substitution of oxygen by sulfur are discussed to get deeper insights on how modifications in electronic structure and nuclear potential can affect equilibrium geometries. With respect to our previous works, we perform non-linear constrained optimizations of equilibrium SE structures with a new general and user-friendly software under development in our group with updated definition of useful statistical indicators.
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Ai Y, Xia S, Liao RZ. Theoretical Studies on the Photochemistry of Pentose Aminooxazoline, a Hypothetical Intermediate Product in the Prebiotic Synthetic Scenario of RNA Nucleotides. J Phys Chem B 2016; 120:9329-37. [PMID: 27525736 DOI: 10.1021/acs.jpcb.6b06061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
2-Aminooxazole is generally considered a prebiotic precursor of ribonucleotides on the early earth. Its pentose compound, pentose aminooxazoline, has been suggested to be a key intermediate in the prebiotic synthetic scenario. In this article, detailed mechanism of the photochemistry of pentose aminooxazoline has been studied by performing density functional theory and multireference complete active space self-consistent field calculations. Parallel to the "ring-puckering" process, which leads to ultrafast nonradiative deactivation, several other photodissociation channels are explored in detail. In addition, the influences of the pentose structure and solvation effects with both implicit and explicit water models have been uncovered for both neutral and protonated forms. The current theoretical results provide very important information not only for the photostability of RNA nucleotides but also for an in-depth understanding of the synthesis of other prebiotic nucleotides.
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Affiliation(s)
- Yuejie Ai
- School of Environmental and Chemical Engineering, North China Electric Power University , Beijing 102206, China
| | - Shuhua Xia
- College of Life and Environmental Science, Minzu University of China , Beijing 100081, China
| | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology , Wuhan 430074, China
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Pei L, Farrar JM. Velocity Map Imaging Study of Ion–Radical Chemistry: Charge Transfer and Carbon–Carbon Bond Formation in the Reactions of Allyl Radicals with C+. J Phys Chem A 2016; 120:6122-8. [DOI: 10.1021/acs.jpca.6b05699] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Linsen Pei
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - James M. Farrar
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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Puzzarini C. Isomerism of Cyanomethanimine: Accurate Structural, Energetic, and Spectroscopic Characterization. J Phys Chem A 2015; 119:11614-22. [DOI: 10.1021/acs.jpca.5b09489] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cristina Puzzarini
- Dipartimento di Chimica “Giacomo
Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy
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Vazart F, Latouche C, Cimino P, Barone V. Accurate Infrared (IR) Spectra for Molecules Containing the C≡N Moiety by Anharmonic Computations with the Double Hybrid B2PLYP Density Functional. J Chem Theory Comput 2015; 11:4364-9. [PMID: 26575929 DOI: 10.1021/acs.jctc.5b00638] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, we report a comprehensive benchmark of C≡N stretching vibrations computed at harmonic and anharmonic levels with the aim of proposing and validating a reliable computational strategy to get accurate results for this puzzling vibrational mode without any ad hoc scaling factor. Anharmonic calculations employing second-order vibrational perturbation theory provide very good results when performed using the B2PLYP double-hybrid functional, in conjunction with an extended basis set and supplemented by semiempirical dispersion contributions. For larger systems, B2PLYP harmonic frequencies, together with B3LYP anharmonic corrections, offer a very good compromise between accuracy and computational cost without the need of any empirical scaling factor.
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Affiliation(s)
- Fanny Vazart
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Camille Latouche
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Paola Cimino
- Dipartimento di Farmacia (DIFARMA), Università di Salerno , via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy
| | - Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
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Vazart F, Calderini D, Skouteris D, Latouche C, Barone V. Reassessment of the Thermodynamic, Kinetic, and Spectroscopic Features of Cyanomethanimine Derivatives: A Full Anharmonic Perturbative Treatment. J Chem Theory Comput 2015; 11:1165-71. [PMID: 26579765 DOI: 10.1021/ct501147a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein we report a full thermodynamic and vibrational investigation of C-cyanomethanimine isomers rooted into the Density Functional Theory (DFT) and the second-order vibrational perturbation theory (VPT2). We show that an anharmonic treatment affects dramatically the vibrational behavior of the molecules, especially thanks to the inclusion of interaction terms between the various modes. Furthermore, the equilibrium constant between the isomers, as well as the rate constant, have been obtained at both harmonic and anharmonic levels showing, as expected, slight but non-negligible differences. To support our investigation, dispersion effects have been employed.
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Affiliation(s)
- Fanny Vazart
- Scuola Normale Superiore , piazza dei Cavalieri 7, 56125 Pisa, Italy
| | - Danilo Calderini
- Scuola Normale Superiore , piazza dei Cavalieri 7, 56125 Pisa, Italy
| | | | - Camille Latouche
- Scuola Normale Superiore , piazza dei Cavalieri 7, 56125 Pisa, Italy
| | - Vincenzo Barone
- Scuola Normale Superiore , piazza dei Cavalieri 7, 56125 Pisa, Italy
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41
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42
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Roberts GM, Marroux HJB, Grubb MP, Ashfold MNR, Orr-Ewing AJ. On the Participation of Photoinduced N–H Bond Fission in Aqueous Adenine at 266 and 220 nm: A Combined Ultrafast Transient Electronic and Vibrational Absorption Spectroscopy Study. J Phys Chem A 2014; 118:11211-25. [DOI: 10.1021/jp508501w] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gareth M. Roberts
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Hugo J. B. Marroux
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Michael P. Grubb
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Michael N. R. Ashfold
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J. Orr-Ewing
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
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Parker DSN, Mebel AM, Kaiser RI. The role of isovalency in the reactions of the cyano (CN), boron monoxide (BO), silicon nitride (SiN), and ethynyl (C2H) radicals with unsaturated hydrocarbons acetylene (C2H2) and ethylene (C2H4). Chem Soc Rev 2014; 43:2701-13. [DOI: 10.1039/c3cs60328h] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The classification of chemical reactions based on shared characteristics is at the heart of the chemical sciences, and is well exemplified by Langmuir's concept of isovalency, in which ‘two molecular entities with the same number of valence electrons have similar chemistries’.
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Affiliation(s)
- D. S. N. Parker
- Department of Chemistry
- University of Hawai'i at Manoa
- Honolulu, USA
| | - A. M. Mebel
- Department of Chemistry and Biochemistry
- Florida International University
- Miami, USA
| | - R. I. Kaiser
- Department of Chemistry
- University of Hawai'i at Manoa
- Honolulu, USA
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44
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Roberts GM, Stavros VG. The role of πσ* states in the photochemistry of heteroaromatic biomolecules and their subunits: insights from gas-phase femtosecond spectroscopy. Chem Sci 2014. [DOI: 10.1039/c3sc53175a] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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45
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Production of ions at high energy and its role in extraterrestrial environments. RENDICONTI LINCEI-SCIENZE FISICHE E NATURALI 2012. [DOI: 10.1007/s12210-012-0215-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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46
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Balucani N, Skouteris D, Leonori F, Petrucci R, Hamberg M, Geppert WD, Casavecchia P, Rosi M. Combined crossed beam and theoretical studies of the N(2D) + C2H4 reaction and implications for atmospheric models of Titan. J Phys Chem A 2012; 116:10467-79. [PMID: 23016665 DOI: 10.1021/jp3072316] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dynamics of the H displacement channels in the reaction N((2)D) + C(2)H(4) have been investigated by the crossed molecular beam technique with mass spectrometric detection and time-of-flight analysis at two different collision energies (17.2 and 28.2 kJ/mol). The interpretation of the scattering results is assisted by new electronic structure calculations of stationary points and product energetics for the C(2)H(4)N ground state doublet potential energy surface. RRKM statistical calculations have been performed to derive the product branching ratio under the conditions of the present experiments and of the atmosphere of Titan. Similarities and differences with respect to a recent study performed in crossed beam experiments coupled to ionization via tunable VUV synchrotron radiation are discussed (Lee, S.-H.; et al. Phys. Chem. Chem. Phys.2011, 13, 8515-8525). Implications for the atmospheric chemistry of Titan are presented.
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Affiliation(s)
- Nadia Balucani
- Dipartimento di Chimica, Università degli Studi di Perugia, 06123 Perugia, Italy.
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47
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Bane MK, Thompson CD, Appadoo DRT, McNaughton D. Synchrotron far infrared spectroscopy of the ground, ν5, and ν15 states of thiirane. J Chem Phys 2012; 137:084306. [DOI: 10.1063/1.4747191] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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48
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Roberts GM, Williams CA, Young JD, Ullrich S, Paterson MJ, Stavros VG. Unraveling Ultrafast Dynamics in Photoexcited Aniline. J Am Chem Soc 2012; 134:12578-89. [DOI: 10.1021/ja3029729] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gareth M. Roberts
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4
7AL, United Kingdom
| | - Craig A. Williams
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4
7AL, United Kingdom
| | - Jamie D. Young
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4
7AL, United Kingdom
| | - Susanne Ullrich
- Department
of Physics and Astronomy, University of Georgia, Athens, Georgia 30602, United
States
| | - Martin J. Paterson
- Institute of Chemical
Sciences, Heriot-Watt University, Edinburgh,
EH14 4AS, United
Kingdom
| | - Vasilios G. Stavros
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4
7AL, United Kingdom
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Chatterley AS, Horke DA, Verlet JRR. On the intrinsic photophysics of indigo: a time-resolved photoelectron spectroscopy study of the indigo carmine dianion. Phys Chem Chem Phys 2012; 14:16155-61. [DOI: 10.1039/c2cp43275g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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50
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Roberts GM, Williams CA, Paterson MJ, Ullrich S, Stavros VG. Comparing the ultraviolet photostability of azole chromophores. Chem Sci 2012. [DOI: 10.1039/c2sc01000c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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