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Simbizi R, Gahungu G, Nguyen MT. Theoretical investigation of protonated thiophene and two of its nitrile substituted derivatives (2-cyanothiophene and 3-cyanothiophene). Phys Chem Chem Phys 2020; 22:24735-24743. [PMID: 33107518 DOI: 10.1039/d0cp03154b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Theoretical and experimental spectroscopic data for protonated cyano-thiophenes (R-CNH+ with R = C4H3S), which are needed for their interstellar search and/or detection, are still lacking in the literature. Considering the high abundance and reactivity of H3+ in the interstellar medium (ISM), a quantum chemical investigation on protonated thiophene and two of its nitrile-substituted derivatives (2-cyanothiophene and 3-cyanothiophene) is undertaken for their characterization. The geometrical structures for the title species are calculated at the M06-2X/6-31G(d,p) level of theory, followed by an empirical correction for systematic errors. At the same level of theory, IR and Raman spectra are explored and the rotational parameters are calculated. The proton affinity (PA) of R-CN and the enthalpy, entropy and Gibbs free energy changes (ΔrH, ΔrS and ΔrG) of the reactions producing R-CNH+ are computed at the G2(MP2) and G3B3 levels of theory and at different temperatures. The PA calculations show that the protonation favors the nitrogen atom, while ΔrH, ΔrS, and ΔrG reveal the spontaneous reactions producing R-CNH+ and their neutral forms. In addition, quadrupole hyperfine structures are predicted, while the region where the brightest lines fall at different temperatures is discussed. These results are expected to assist astrophysicists and astrochemists in the search for new species in the ISM.
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Affiliation(s)
- René Simbizi
- Département de Physique, Faculté des Sciences Université du Burundi, B.P. 2700 Bujumbura, Burundi.
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52
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Mardyukov A, Keul F, Schreiner PR. Preparation and characterization of the enol of acetamide: 1-aminoethenol, a high-energy prebiotic molecule. Chem Sci 2020; 11:12358-12363. [PMID: 34094445 PMCID: PMC8162875 DOI: 10.1039/d0sc04906a] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/19/2020] [Indexed: 11/21/2022] Open
Abstract
Amide tautomers, which constitute the higher-energy amide bond linkage, not only are key for a variety of biological but also prebiotic processes. In this work, we present the gas-phase synthesis of 1-aminoethenol, the higher-energy tautomer of acetamide, that has not been spectroscopically identified to date. The title compound was prepared by flash vacuum pyrolysis of malonamic acid and was characterized employing matrix isolation infrared as well as ultraviolet/visible spectroscopy. Coupled-cluster computations at the AE-CCSD(T)/cc-pVTZ level of theory support the spectroscopic assignments. Upon photolysis at λ > 270 nm, the enol rearranges to acetamide as well as ketene and ammonia. As the latter two are even higher in energy, they constitute viable starting materials for formation of the title compound.
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Affiliation(s)
- Artur Mardyukov
- Institute of Organic Chemistry, Justus Liebig University Heinrich-Buff-Ring 17 35392 Giessen Germany
| | - Felix Keul
- Institute of Organic Chemistry, Justus Liebig University Heinrich-Buff-Ring 17 35392 Giessen Germany
| | - Peter R Schreiner
- Institute of Organic Chemistry, Justus Liebig University Heinrich-Buff-Ring 17 35392 Giessen Germany
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53
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Sagi R, Akerman M, Ramakrishnan S, Asscher M. The role of thermal history on spontaneous polarization and phase transitions of amorphous solid water films studied by contact potential difference measurements. J Chem Phys 2020; 153:144702. [DOI: 10.1063/5.0017712] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Roey Sagi
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat-Ram, Jerusalem 9190401, Israel
| | - Michelle Akerman
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat-Ram, Jerusalem 9190401, Israel
| | - Sujith Ramakrishnan
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat-Ram, Jerusalem 9190401, Israel
| | - Micha Asscher
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat-Ram, Jerusalem 9190401, Israel
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54
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Sagi R, Akerman M, Ramakrishnan S, Asscher M. Spontaneous polarization of thick solid ammonia films. J Chem Phys 2020; 153:124707. [DOI: 10.1063/5.0017853] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Roey Sagi
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Michelle Akerman
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Sujith Ramakrishnan
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Micha Asscher
- Institute of Chemistry, Edmond J. Safra Campus, Givat-Ram, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
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55
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Rotational spectrum simulations of asymmetric tops in an astrochemical context. J Mol Model 2020; 26:278. [PMID: 32960366 DOI: 10.1007/s00894-020-04523-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/26/2020] [Indexed: 10/23/2022]
Abstract
Rotational spectroscopy plays a major role in the field of observational astrochemistry, enabling the detection of more than 200 species including a plethora of complex organic molecules in different space environments. Those line detections allow correctly determining the sources and physical properties, as well as exploring their morphology, evolutionary stage, and chemical evolution pathways. In this context, quantum chemistry is a powerful tool to the investigation of the molecular inventory of astrophysical environments, guiding laboratory experiments and assisting in both line assignments and extrapolation of the experimental data to unexplored frequency ranges. In the present work, we start by briefly reviewing the rotational model Hamiltonian for asymmetric tops beyond the rigid-rotor approximation, including rotational-vibrational, centrifugal, and anharmonic effects. Then, aiming at further contributing to the recording and analysis of laboratory microwave spectroscopy by means of accessible, less demanding quantum chemical methods, we performed density functional theory (DFT) calculations of the spectroscopic parameters of astrochemically relevant species, followed by their rotational spectrum simulations. Furthermore, dispersion-correction effects combined with different functionals were also investigated. Case studies are the asymmetric tops H2CO, H2CS, c-HCOOH, t-HCOOH, and HNCO. Spectroscopic parameter predictions were overall very close to experiment, with mean percentage errors smaller than 1% for zeroth order and [Formula: see text] for first-order constants. We discuss the implications and impacts of those constants on spectrum simulations, and compare line-frequency predictions at millimeter wavelengths. Moreover, theoretical spectroscopic parameters of c-HCOOH and HNCO are introduced for the first time in this work.
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56
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Kossoski F, Barbatti M. Nonadiabatic dynamics in multidimensional complex potential energy surfaces. Chem Sci 2020; 11:9827-9835. [PMID: 34094243 PMCID: PMC8162122 DOI: 10.1039/d0sc04197a] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Despite the continuous development of theoretical methodologies for describing nonadiabatic dynamics of molecular systems, there is a lack of approaches for processes where the norm of the wave function is not conserved, i.e., when an imaginary potential accounts for some irreversible decaying mechanism. Current approaches rely on building potential energy surfaces of reduced dimensionality, which is not optimal for more involving and realistic multidimensional problems. Here, we present a novel methodology for describing the dynamics of complex-valued molecular Hamiltonians, which is a generalisation of the trajectory surface hopping method. As a first application, the complex surface fewest switches surface hopping (CS-FSSH) method was employed to survey the relaxation mechanisms of the shape resonant anions of iodoethene. We have provided the first detailed and dynamical picture of the π*/σ* mechanism of dissociative electron attachment in halogenated unsaturated compounds, which is believed to underlie electron-induced reactions of several molecules of interest. Electron capture into the π* orbital promotes C
Created by potrace 1.16, written by Peter Selinger 2001-2019
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C stretching and out-of-plane vibrations, followed by charge transfer from the double bond into the σ* orbital at the C–I bond, and, finally, release of the iodine ion, all within only 15 fs. On-the-fly dynamics simulations of a vast class of processes can be envisioned with the CS-FSSH methodology, including autoionisation from transient anions, core-ionised and superexcited states, Auger and interatomic coulombic decay, and time-dependent luminescence. Despite the continuous development of methods for describing nonadiabatic dynamics, there is a lack of multidimensional approaches for processes where the wave function norm is not conserved. A new surface hopping variant closes this knowledge gap.![]()
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Ryazantsev SV, Zasimov PV, Feldman VI. Radiation-induced synthesis of formic acid in the H2O–CO system: A matrix isolation study. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2020.137540] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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58
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Investigating the biological potential of galactic cosmic ray-induced radiation-driven chemical disequilibrium in the Martian subsurface environment. Sci Rep 2020; 10:11646. [PMID: 32724041 PMCID: PMC7387464 DOI: 10.1038/s41598-020-68715-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/26/2020] [Indexed: 11/08/2022] Open
Abstract
There is growing evidence suggesting the presence of aqueous environment on ancient Mars, raising the question of the possibility of life in such an environment. Subsequently, with the erosion of the Martian atmosphere resulting in drastic changes in its climate, surface water disappeared, shrinking habitable spaces on the planet, with only a limited amount of water remaining near the surface in form of brines and water-ice deposits. Life, if it ever existed, would have had to adapt to harsh modern conditions, which includes low temperatures and surface pressure, and high radiation dose. Presently, there is no evidence of any biological activity on the planet's surface, however, the subsurface environment, which is yet to be explored, is less harsh, has traces of water in form of water-ice and brines, and undergoes radiation-driven redox chemistry. I hypothesize that Galactic Cosmic Ray (GCR)-induced radiation-driven chemical disequilibrium can be used for metabolic energy by extant life, and host organisms using mechanisms seen in similar chemical and radiation environments on Earth. I propose a GCR-induced radiolytic zone, and discuss the prospects of finding such life with Rosalind Franklin rover of the ExoMars mission.
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59
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Potapov A, Jäger C, Henning T. Ice Coverage of Dust Grains in Cold Astrophysical Environments. PHYSICAL REVIEW LETTERS 2020; 124:221103. [PMID: 32567895 DOI: 10.1103/physrevlett.124.221103] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/14/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
Surface processes on cosmic solids in cold astrophysical environments lead to gas-phase depletion and molecular complexity. Most astrophysical models assume that the molecular ice forms a thick multilayer substrate, not interacting with the dust surface. In contrast, we present experimental results demonstrating the importance of the surface for porous grains. We show that cosmic dust grains may be covered by a few monolayers of ice only. This implies that the role of dust surface structure, composition, and reactivity in models describing surface processes in cold interstellar, protostellar, and protoplanetary environments has to be reevaluated.
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Affiliation(s)
- Alexey Potapov
- Laboratory Astrophysics Group of the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena, Institute of Solid State Physics, Helmholtzweg 3, 07743 Jena, Germany
| | - Cornelia Jäger
- Laboratory Astrophysics Group of the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena, Institute of Solid State Physics, Helmholtzweg 3, 07743 Jena, Germany
| | - Thomas Henning
- Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg, Germany
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60
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Rani N, Vikas. Extra‐Terrestrial Gas‐Phase Stereoinversion in Amino Acid Leucine: Thermal and Photochemical Channels. Chemphyschem 2020. [DOI: 10.1002/cphc.202000230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Namrata Rani
- Quantum Chemistry Group, Department of Chemistry & Centre of Advanced Studies in ChemistryPanjab University Chandigarh 160014 India
| | - Vikas
- Quantum Chemistry Group, Department of Chemistry & Centre of Advanced Studies in ChemistryPanjab University Chandigarh 160014 India
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61
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A never-ending story in the sky: The secrets of chemical evolution. Phys Life Rev 2020; 32:59-94. [DOI: 10.1016/j.plrev.2019.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/26/2019] [Accepted: 07/02/2019] [Indexed: 01/13/2023]
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62
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Ventura ON. From science-fiction to present life. Phys Life Rev 2020; 32:121-123. [DOI: 10.1016/j.plrev.2019.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 09/23/2019] [Indexed: 11/25/2022]
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63
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Alvarez-Ibarra A, Parise A, Hasnaoui K, de la Lande A. The physical stage of radiolysis of solvated DNA by high-energy-transfer particles: insights from new first principles simulations. Phys Chem Chem Phys 2020; 22:7747-7758. [DOI: 10.1039/d0cp00165a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Electron dynamics simulations based on density functional theory are carried out on nanometric molecular systems to decipher the primary processes following irradiation of bio-macromolecules by high energy transfer charged particles.
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Affiliation(s)
| | - Angela Parise
- Université Paris-Saclay
- CNRS
- Institut de Chimie Physique UMR8000
- Orsay
- France
| | - Karim Hasnaoui
- Institut du Développement et des Ressources en Informatique Scientifique
- Rue John von Neumann
- Orsay
- France
- Maison de la Simulation
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64
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Wolf ME, Hoobler PR, Turney JM, Schaefer HF. Important features of the potential energy surface of the methylamine plus O( 1D) reaction. Phys Chem Chem Phys 2019; 21:24194-24205. [PMID: 31659355 DOI: 10.1039/c9cp05039f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This research presents an ab initio characterization of the potential energy surface for the methylamine plus 1D oxygen atom reaction, which may be relevant to interstellar chemistry. Geometries and harmonic vibrational frequencies were determined for all stationary points at the CCSD(T)/aug-cc-pVTZ level of theory. The focal point method along with several additive corrections was used to obtain reliable CCSDT(Q)/CBS potential energy surface features. Extensive conformational analysis and intrinsic reaction coordinate computations were performed to ensure accurate chemical connectivity of the stationary points. Five minima were determined to be possible products of this reaction and three novel transition states were found that were previously unreported or mislabeled in the literature. The pathways we present can be used to guide further searches for NH2 containing species in the interstellar medium.
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Affiliation(s)
- Mark E Wolf
- Center for Computational Quantum Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA.
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65
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Parise A, de la Lande A, Marino T, Russo N. Attosecond dynamics simulations of glycine irradiated by α-particle: Comment on "A never-ending story in the sky: The secrets of chemical evolution" by C. Puzzarini and V. Barone. Phys Life Rev 2019; 32:114-116. [PMID: 31451435 DOI: 10.1016/j.plrev.2019.08.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 08/19/2019] [Indexed: 11/16/2022]
Affiliation(s)
- Angela Parise
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Rende (CS), Italy; Laboratoire de Chimie Physique, Université Paris Sud, CNRS, Université Paris Saclay, 15 avenue Jean Perrin, F91405 Orsay, France
| | - Aurelien de la Lande
- Laboratoire de Chimie Physique, Université Paris Sud, CNRS, Université Paris Saclay, 15 avenue Jean Perrin, F91405 Orsay, France
| | - Tiziana Marino
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Rende (CS), Italy
| | - Nino Russo
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Rende (CS), Italy.
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