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Stylianakis I, Zervos N, Lii JH, Pantazis DA, Kolocouris A. Conformational energies of reference organic molecules: benchmarking of common efficient computational methods against coupled cluster theory. J Comput Aided Mol Des 2023; 37:607-656. [PMID: 37597063 PMCID: PMC10618395 DOI: 10.1007/s10822-023-00513-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 06/03/2023] [Indexed: 08/21/2023]
Abstract
We selected 145 reference organic molecules that include model fragments used in computer-aided drug design. We calculated 158 conformational energies and barriers using force fields, with wide applicability in commercial and free softwares and extensive application on the calculation of conformational energies of organic molecules, e.g. the UFF and DREIDING force fields, the Allinger's force fields MM3-96, MM3-00, MM4-8, the MM2-91 clones MMX and MM+, the MMFF94 force field, MM4, ab initio Hartree-Fock (HF) theory with different basis sets, the standard density functional theory B3LYP, the second-order post-HF MP2 theory and the Domain-based Local Pair Natural Orbital Coupled Cluster DLPNO-CCSD(T) theory, with the latter used for accurate reference values. The data set of the organic molecules includes hydrocarbons, haloalkanes, conjugated compounds, and oxygen-, nitrogen-, phosphorus- and sulphur-containing compounds. We reviewed in detail the conformational aspects of these model organic molecules providing the current understanding of the steric and electronic factors that determine the stability of low energy conformers and the literature including previous experimental observations and calculated findings. While progress on the computer hardware allows the calculations of thousands of conformations for later use in drug design projects, this study is an update from previous classical studies that used, as reference values, experimental ones using a variety of methods and different environments. The lowest mean error against the DLPNO-CCSD(T) reference was calculated for MP2 (0.35 kcal mol-1), followed by B3LYP (0.69 kcal mol-1) and the HF theories (0.81-1.0 kcal mol-1). As regards the force fields, the lowest errors were observed for the Allinger's force fields MM3-00 (1.28 kcal mol-1), ΜΜ3-96 (1.40 kcal mol-1) and the Halgren's MMFF94 force field (1.30 kcal mol-1) and then for the MM2-91 clones MMX (1.77 kcal mol-1) and MM+ (2.01 kcal mol-1) and MM4 (2.05 kcal mol-1). The DREIDING (3.63 kcal mol-1) and UFF (3.77 kcal mol-1) force fields have the lowest performance. These model organic molecules we used are often present as fragments in drug-like molecules. The values calculated using DLPNO-CCSD(T) make up a valuable data set for further comparisons and for improved force field parameterization.
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Affiliation(s)
- Ioannis Stylianakis
- Department of Medicinal Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15771, Athens, Greece
| | - Nikolaos Zervos
- Department of Medicinal Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15771, Athens, Greece
| | - Jenn-Huei Lii
- Department of Chemistry, National Changhua University of Education, Changhua City, Taiwan
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Antonios Kolocouris
- Department of Medicinal Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15771, Athens, Greece.
- Laboratory of Medicinal Chemistry, Section of Pharmaceutical Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, 15771, Athens, Greece.
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Melosso M, Jiang N, Gauss J, Puzzarini C. Hyperfine-resolved spectra of HDS together with a global ro-vibrational analysis. J Chem Phys 2023; 158:2888208. [PMID: 37139997 DOI: 10.1063/5.0148810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 04/17/2023] [Indexed: 05/05/2023] Open
Abstract
Despite their chemical simplicity, the spectroscopic investigation of light hydrides, such as hydrogen sulfide, is challenging due to strong hyperfine interactions and/or anomalous centrifugal-distortion effects. Several hydrides have already been detected in the interstellar medium, and the list includes H2S and some of its isotopologues. Astronomical observation of isotopic species and, in particular, those bearing deuterium is important to gain insights into the evolutionary stage of astronomical objects and to shed light on interstellar chemistry. These observations require a very accurate knowledge of the rotational spectrum, which is so far limited for mono-deuterated hydrogen sulfide, HDS. To fill this gap, high-level quantum-chemical calculations and sub-Doppler measurements have been combined for the investigation of the hyperfine structure of the rotational spectrum in the millimeter- and submillimeter-wave region. In addition to the determination of accurate hyperfine parameters, these new measurements together with the available literature data allowed us to extend the centrifugal analysis using a Watson-type Hamiltonian and a Hamiltonian-independent approach based on the Measured Active Ro-Vibrational Energy Levels (MARVEL) procedure. The present study thus permits to model the rotational spectrum of HDS from the microwave to far-infrared region with great accuracy, thereby accounting for the effect of the electric and magnetic interactions due to the deuterium and hydrogen nuclei.
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Affiliation(s)
- Mattia Melosso
- Dipartimento di Chimica "Giacomo Ciamician," Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy
| | - Ningjing Jiang
- Dipartimento di Chimica "Giacomo Ciamician," Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy
| | - Jürgen Gauss
- Department Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Cristina Puzzarini
- Dipartimento di Chimica "Giacomo Ciamician," Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy
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Liu Y, Shen J, Dong Y, Zhu L, Li C, Wang D, Huang W. Data storage and encryption with a high security level based on molecular configurational isomers. SOFT MATTER 2022; 18:6599-6606. [PMID: 35997044 DOI: 10.1039/d2sm00890d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Developing advanced materials for highly secure data-encryption is crucial but very challenging, as most data-encryption materials (the message area) are chemically different from the substrates (the background) on which they are being written, leading to high risks of data leakage by deciphering via sophisticated instrumental analysis. Additionally, most materials require only one stimulus for decryption, resulting in a low-level of data-security. Here, a three configurational isomer-based data-encryption method is developed (i.e., propylamine, isopropylamine, and cyclopropylamine). Their similar molecular formulae, elemental constitution, and physiochemical properties make them ideal date-encryption materials. On the other hand, the significant differences in lower critical solution temperatures (LCST) of the corresponding polyacrylamides, i.e., 10 °C for poly(N-propylacrylamide), 32 °C for poly(N-isopropylacrylamide), and 53 °C for poly(N-cyclopropylacrylamide), respectively, render an effective method for data decryption. Relying on the above features, the data written by three isomers are well-hidden under given conditions. And a specific temperature range, rather than a simple temperature increase or decrease, would be required for decryption. Furthermore, undesired temperatures give wrong outputs, which is highly deceptive to the hacker. Therefore, a high-level of data security can be achieved. This result opens a new door for designing advanced materials for improving the data-security level.
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Affiliation(s)
- Yang Liu
- College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, 350002, Fujian, P. R. China.
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
- Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian, 350002, P. R. China
| | - Jinghui Shen
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
- Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian, 350002, P. R. China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, P. R. China
| | - Yu Dong
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, P. R. China
| | - Lijuan Zhu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
| | - Caicong Li
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
| | - Donghui Wang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, P. R. China
| | - Weiguo Huang
- College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, 350002, Fujian, P. R. China.
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China
- Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian, 350002, P. R. China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, P. R. China
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Bizzocchi L, Alessandrini S, Melosso M, Rivilla VM, Puzzarini C. Ab Initio Study of Fine and Hyperfine Interactions in Triplet POH. Molecules 2022; 27:302. [PMID: 35011533 PMCID: PMC8746536 DOI: 10.3390/molecules27010302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/28/2021] [Accepted: 12/30/2021] [Indexed: 11/16/2022] Open
Abstract
Phosphorous-containing molecules have a great relevance in prebiotic chemistry in view of the fact that phosphorous is a fundamental constituent of biomolecules, such as RNA, DNA, and ATP. Its biogenic importance has led astrochemists to investigate the possibility that P-bearing species could have formed in the interstellar medium (ISM) and subsequently been delivered to early Earth by rocky bodies. However, only two P-bearing molecules have been detected so far in the ISM, with the chemistry of interstellar phosphorous remaining poorly understood. Here, in order to shed further light on P-carriers in space, we report a theoretical spectroscopic characterisation of the rotational spectrum of POH in its 3A″ ground electronic state. State-of-the-art coupled-cluster schemes have been employed to derive rotational constants, centrifugal distortion terms, and most of the fine and hyperfine interaction parameters, while the electron spin-spin dipolar coupling has been investigated using the multi-configuration self-consistent-field method. The computed spectroscopic parameters have been used to simulate the appearance of triplet POH rotational and ro-vibrational spectra in different conditions, from cold to warm environments, either in gas-phase experiments or in molecular clouds. Finally, we point out that the predicted hyperfine structures represent a key pattern for the recognition of POH in laboratory and interstellar spectra.
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Affiliation(s)
- Luca Bizzocchi
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy; (L.B.); (S.A.)
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via F. Selmi 2, 40126 Bologna, Italy;
| | - Silvia Alessandrini
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy; (L.B.); (S.A.)
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via F. Selmi 2, 40126 Bologna, Italy;
| | - Mattia Melosso
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via F. Selmi 2, 40126 Bologna, Italy;
- Scuola Superiore Meridionale, Università di Napoli Federico II, Largo San Marcellino 10, 80138 Naples, Italy
| | - Víctor M. Rivilla
- Centro de Astrobiología (CSIC-INTA), Ctra. de Ajalvir Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain;
- INAF—Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Florence, Italy
| | - Cristina Puzzarini
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via F. Selmi 2, 40126 Bologna, Italy;
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Silva WGDP, Daudet G, Perez S, Thorwirth S, van Wijngaarden J. Conformational preferences of diallylamine: A rotational spectroscopic and theoretical study. J Chem Phys 2021; 154:164303. [PMID: 33940826 DOI: 10.1063/5.0048699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The conformational space of diallylamine (DAA) was investigated using rotational spectroscopy from 7 to 19 GHz aided by quantum chemical calculations. Extensive conformational searches using density functional theory B3LYP-D3(BJ) and the ab initio MP2 method with the aug-cc-pVTZ basis set identified a total of 42 minima for DAA within ∼22 kJ mol-1. This reveals a strikingly rich conformational landscape for this secondary amine with two equivalent substituents. Experimentally, transitions belonging to four low energy conformers (I, II, III, and IV) were unequivocally assigned in the rotational spectrum, and their patterns were confirmed by the presence of the hyperfine structure owing to the 14N quadrupolar nucleus. The relative intensities of the observed transitions suggest a conformational energy ordering of I < II < III < IV. Natural bond orbital and non-covalent interaction calculations reveal that the geometric preferences for the observed conformers are governed by an interplay of subtle attractive interactions (including hyperconjugation involving the lone pair at nitrogen) and repulsive effects.
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Affiliation(s)
- Weslley G D P Silva
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Gabrielle Daudet
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Sem Perez
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Sven Thorwirth
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany
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Melli A, Potenti S, Melosso M, Herbers S, Spada L, Gualandi A, Lengsfeld KG, Dore L, Buschmann P, Cozzi PG, Grabow J, Barone V, Puzzarini C. A Journey from Thermally Tunable Synthesis to Spectroscopy of Phenylmethanimine in Gas Phase and Solution. Chemistry 2020; 26:15016-15022. [PMID: 32717136 PMCID: PMC7756512 DOI: 10.1002/chem.202003270] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Indexed: 11/11/2022]
Abstract
Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine-intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state-of-the-art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined.
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Affiliation(s)
- Alessio Melli
- Scuola Normale SuperiorePiazza dei Cavalieri 756126PisaItaly
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Simone Potenti
- Scuola Normale SuperiorePiazza dei Cavalieri 756126PisaItaly
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Mattia Melosso
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Sven Herbers
- Institut für Physikalische Chemie und ElektrochemieGottfried Wilhelm Leibniz Universität HannoverCallinstraße 3A30167HannoverGermany
| | - Lorenzo Spada
- Scuola Normale SuperiorePiazza dei Cavalieri 756126PisaItaly
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Andrea Gualandi
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Kevin G. Lengsfeld
- Institut für Physikalische Chemie und ElektrochemieGottfried Wilhelm Leibniz Universität HannoverCallinstraße 3A30167HannoverGermany
| | - Luca Dore
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Philipp Buschmann
- Institut für Physikalische Chemie und ElektrochemieGottfried Wilhelm Leibniz Universität HannoverCallinstraße 3A30167HannoverGermany
| | - Pier Giorgio Cozzi
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
| | - Jens‐Uwe Grabow
- Institut für Physikalische Chemie und ElektrochemieGottfried Wilhelm Leibniz Universität HannoverCallinstraße 3A30167HannoverGermany
| | - Vincenzo Barone
- Scuola Normale SuperiorePiazza dei Cavalieri 756126PisaItaly
| | - Cristina Puzzarini
- Dipartimento di Chimica “Giacomo Ciamician”Universitá di BolognaVia Selmi 240126BolognaItaly
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Alessandrini S, Dell'Isola V, Spada L, Barone V, Puzzarini C. A computational journey in the CH 2O 2S land: an accurate rotational and ro-vibrational analysis of the sulfene molecule and the O,S- and O,O-monothiocarbonic acids. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1766707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- S. Alessandrini
- Scuola Normale Superiore, Pisa, Italy
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Bologna, Italy
| | - V. Dell'Isola
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Bologna, Italy
| | - L. Spada
- Scuola Normale Superiore, Pisa, Italy
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Bologna, Italy
| | - V. Barone
- Scuola Normale Superiore, Pisa, Italy
| | - C. Puzzarini
- Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Bologna, Italy
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Jin Y, Lu T, Feng G. The preferred conformation of the tetrafluoro-1,3-dithietane⋯isopropylamine complex as revealed by rotational spectroscopy. Phys Chem Chem Phys 2020; 22:28339-28344. [DOI: 10.1039/d0cp05033d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The favored conformation of the C2F4S2–IPA complex is determined by the strength of the S⋯N ChB as revealed by rotational spectroscopy.
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Affiliation(s)
- Yan Jin
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
| | - Tao Lu
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
| | - Gang Feng
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
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9
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Lu T, Zhang J, Gou Q, Feng G. Structure and C⋯N tetrel-bonding of the isopropylamine–CO2 complex studied by microwave spectroscopy and theoretical calculations. Phys Chem Chem Phys 2020; 22:8467-8475. [DOI: 10.1039/d0cp00925c] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The structural and energetic features of C⋯N tetrel bond and C–H⋯O hydrogen bonds linking CO2 and aliphatic amines were characterized with rotational spectroscopy and quantum chemical calculations.
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Affiliation(s)
- Tao Lu
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
| | - Jiaqi Zhang
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
| | - Qian Gou
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
| | - Gang Feng
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing
- China
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Puzzarini C, Barone V. The challenging playground of astrochemistry: an integrated rotational spectroscopy - quantum chemistry strategy. Phys Chem Chem Phys 2020; 22:6507-6523. [PMID: 32163090 DOI: 10.1039/d0cp00561d] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
While it is now well demonstrated that the interstellar medium (ISM) is characterized by a diverse and complex chemistry, a significant number of features in radioastronomical spectra are still unassigned and call for new laboratory efforts, which are increasingly based on integrated experimental and computational strategies. In parallel, the identification of an increasing number of molecules containing more than five atoms and at least one carbon atom (the so-called "interstellar" complex organic molecules), which can play a relevant role in the chemistry of life, raises the additional issue of how these species can be produced in the typical harsh conditions of the ISM. On these grounds, this perspective aims to present an integrated rotational spectroscopy - quantum chemistry approach for supporting radioastronomical observations and a computational strategy for contributing to the elucidation of chemical reactivity in the interstellar space.
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Affiliation(s)
- Cristina Puzzarini
- Dipartimento di Chimica "Giacomo Ciamician", University of Bologna, via F. Selmi 2, I-40126 Bologna, Italy.
| | - Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa, I-56126, Italy
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