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Fortenberry RC. Picking up Good Vibrations through Quartic Force Fields and Vibrational Perturbation Theory. J Phys Chem Lett 2024; 15:6528-6537. [PMID: 38875074 DOI: 10.1021/acs.jpclett.4c01089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2024]
Abstract
Quartic force fields (QFFs) define sparse potential energy surfaces (compared to semiglobal surfaces) that are the cheapest and easiest means of computing anharmonic vibrational frequencies, especially when utilized with second-order vibrational perturbation theory (VPT2). However, flat and shallow potential surfaces are exceedingly difficult for QFFs to treat through a combination of numerical noise in the often numerically computed derivatives and in competing energy factors in the composite energies often utilized to provide high-level spectroscopic predictions. While some of these issues can be alleviated with analytic derivatives, hybrid QFFs, and intelligent choices in coordinate systems, the best practice is for predicting good molecular vibrations via QFFs is to understand what they cannot do, and this manuscript documents such cases where QFFs may fail.
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Affiliation(s)
- Ryan C Fortenberry
- Department of Chemistry & Biochemistry, University of Mississippi, University, Mississippi 38677-1848, United States
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2
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Patel P, Chung J, Bowman MA, Ulusoy I, Wilson AK. Potential energy surfaces and dynamic properties via ab initio composite and density functional approaches. J Comput Chem 2024; 45:1352-1363. [PMID: 38376255 DOI: 10.1002/jcc.27333] [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: 09/19/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 02/21/2024]
Abstract
Vibrational spectroscopy enables critical insight into the structural and dynamic properties of molecules. Presently, the majority of theoretical approaches to spectroscopy employ wavefunction-based ab initio or density functional methods that rely on the harmonic approximation. This approximation breaks down for large molecules with strongly anharmonic bonds or for molecules with large internuclear separations. An alternative to these methods involves generating molecular anharmonic potential energy surfaces (potentials) and using them to extrapolate the vibrational frequencies. This study examines the efficacy of density functional theory (DFT) and the correlation consistent Composite Approach (ccCA) in generating anharmonic frequencies from potentials of small main group molecules. Vibrational self-consistent field Theory (VSCF) and post-VSCF methods were used to calculate the fundamental frequencies of these molecules from their potentials. Functional choice, basis set selection, and mode-coupling are also examined as factors in influencing accuracy. The absolute deviations for the calculated frequencies using potentials at the ccCA level of theory were lower than the potentials at the DFT level. With DFT resulting in bending modes that are better described than those of ccCA, a multilevel DFT:ccCA approach where DFT potentials are used for single vibrational mode potentials and ccCA is used for vibrational mode-mode couplings can be utilized for larger polyatomic systems. The frequencies obtained with this multilevel approach using VCIPSI-PT2 were closer to experimental frequencies than the scaled harmonic frequencies, indicating the success of utilizing post-VSCF methods to generate more accurate representations of computed infrared spectra.
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Affiliation(s)
- Prajay Patel
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
- Chemistry Department, University of Dallas, Irving, Texas, USA
| | - Joseph Chung
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Max Aksel Bowman
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Inga Ulusoy
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
- Scientific Software Center, Interdisciplinary Center for Scientific Computing, Heidelberg University, Heidelberg, Germany
| | - Angela K Wilson
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
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3
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Fortenberry RC. Quantum Chemistry and Astrochemistry: A Match Made in the Heavens. J Phys Chem A 2024; 128:1555-1565. [PMID: 38381079 DOI: 10.1021/acs.jpca.3c07601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Quantum chemistry can uniquely answer astrochemical questions that no other technique can provide. Computations can be parallelized, automated, and left to run continuously providing exceptional molecular throughput that cannot be done through experimentation. Additionally, the granularity of the individual computations that are required of potential energy surfaces, reaction mechanism pathways, or other quantum chemically derived observables produces a unique mosaic that make up the larger whole. These pieces can be dissected for their individual contributions or evaluated in an ad hoc fashion for each of their roles in generating the larger whole. No other scientific approach is capable of reporting such fine-grained insights. Quantum chemistry also works from a bottom-up approach in providing properties directly from the desired molecule instead of a top-down perspective as required of experiment where molecules have to be linked to observed phenomena. Furthermore, modern quantum chemistry is well within the range of "chemical accuracy" and is approaching "spectroscopic accuracy." As such, the seemingly difficult questions asked by astrochemistry that would not be asked initially for any other application require quantum chemical reference data. While the results of quantum chemical computations are needed to interpret astrochemical observation, modeling, or laboratory experimentation, such hard questions, regardless of the original need to answer them, produce unique solutions. While questions in astrochemistry often require novel developments in and implementations of quantum chemistry as outlined herein, the applications of these solutions will stretch beyond astrochemistry and may yet impact fields much closer to Earth.
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Affiliation(s)
- Ryan C Fortenberry
- Department of Chemistry & Biochemistry, University of Mississippi, Oxford, Mississippi 38677-1848, United States
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4
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Puzzarini C, Alessandrini S, Bizzocchi L, Melosso M. Hunting for interstellar molecules: rotational spectra of reactive species. Faraday Discuss 2023; 245:309-326. [PMID: 37318358 DOI: 10.1039/d3fd00052d] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Interstellar molecules are often highly reactive species, which are unstable under terrestrial conditions, such as radicals, ions and unsaturated carbon chains. Their detection in space is usually based on the astronomical observation of their rotational fingerprints. However, laboratory investigations have to face the issue of efficiently producing these molecules and preserving them during rotational spectroscopy measurements. A general approach for producing and investigating unstable/reactive species is presented by means of selected case-study molecules. The overall strategy starts from quantum-chemical calculations that aim at obtaining accurate predictions of the missing spectroscopic information required to guide spectral analysis and assignment. Rotational spectra of these species are then recorded by exploiting the approach mentioned above, and their subsequent analysis leads to accurate spectroscopic parameters. These are then used for setting up accurate line catalogs for astronomical searches.
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Affiliation(s)
- Cristina Puzzarini
- ROT&Comp Lab, Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, I-40126 Bologna, Italy.
| | - Silvia Alessandrini
- ROT&Comp Lab, Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, I-40126 Bologna, Italy.
| | - Luca Bizzocchi
- ROT&Comp Lab, Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, I-40126 Bologna, Italy.
| | - Mattia Melosso
- ROT&Comp Lab, Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, I-40126 Bologna, Italy.
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5
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Puzzarini C, Stanton JF. Connections between the accuracy of rotational constants and equilibrium molecular structures. Phys Chem Chem Phys 2023; 25:1421-1429. [PMID: 36562443 DOI: 10.1039/d2cp04706c] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Rotational spectroscopy is the technique of choice for investigating molecular structures in the gas phase. Indeed, rotational constants are strongly connected to the geometry of the molecular system under consideration. Therefore, they are powerful tools for assessing the accuracy that quantum chemical approaches can reach in structural determinations. In this review article, it is shown how it is possible to measure the accuracy of a computed equilibrium geometry based on the comparison of rotational constants. But, it is also addressed what accuracy is required by computations for providing molecular structures and thus rotational constants that are useful to experiment. Quantum chemical methodologies for obtaining the "0.1% accuracy" for rotational constants are reviewed for systems ranging in size from small molecules to small polycyclic aromatic hydrocarbons. This accuracy for systems containing two dozen or so atoms opens the way towards future applications such as the accurate characterization of non-covalent interactions, which play a key role in several biological and technological processes.
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Affiliation(s)
- Cristina Puzzarini
- Dipartimento di Chimica "Giacomo Ciamician", Università di Bologna, via F. Selmi 2, 40126, Bologna, Italy.
| | - John F Stanton
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA.
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Agbaglo DA, Cheng Q, Fortenberry RC, Stanton JF, DeYonker NJ. Theoretical Rovibrational Spectroscopy of Magnesium Tricarbide-Multireference Character Thwarts a Full Analysis of All Isomers. J Phys Chem A 2022; 126:4132-4146. [PMID: 35758849 DOI: 10.1021/acs.jpca.2c01340] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Magnesium tricarbide isomers are studied herein with coupled cluster theory and multireference configuration interaction to support their possible detection in astrochemical environments such as the circumstellar envelope surrounding the star IRC +10216 or in terrestrial laboratories. Magnesium-bearing species may abound in the interstellar medium (ISM), but only eight (MgNC, MgCN, HMgNC, MgC2H, MgC3N, MgC4H, MgC5N, and MgC6H) have been directly identified thus far. Several possible isomers for the related MgC3 system are explored in their singlet and triplet spin multiplicities. Overall, this work offers quantum chemical insight of rovibrational spectroscopic data for MgC3 using quartic force fields (QFFs) based on the CCSD(T) and CCSD(T)-F12 levels of theory at the complete basis set (CBS) limit. Additional corrections with small basis set CCSDT(Q) and scalar relativistic effects are also included in the analysis. Salient multireference character is found in the singlet diamond electronic state, which makes a definitive assignment of the ground state challenging. Nevertheless, coupled cluster-based composite energies and multireference configuration interaction both predict that the 1A1 diamond isomer is 1.6-2.2 kcal mol-1 lower in energy than the 3A1 diamond isomer. Furthermore, highly accurate binding energies of various isomers MgC3 are provided for comparison to photodetachment experiments. Dipole moments along with harmonic infrared intensities will guide efforts for astronomical and spectroscopic characterization.
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Affiliation(s)
- Donatus A Agbaglo
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38151, United States
| | - Qianyi Cheng
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38151, United States
| | - Ryan C Fortenberry
- Department of Chemistry & Biochemistry, University of Mississippi, University, Mississippi 38677-1848, United States
| | - John F Stanton
- Department of Chemistry and Physics, University of Florida, Gainesville, Florida 32611, United States
| | - Nathan J DeYonker
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38151, United States
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Gardner MB, Westbrook BR, Fortenberry RC, Lee TJ. Highly-accurate quartic force fields for the prediction of anharmonic rotational constants and fundamental vibrational frequencies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 248:119184. [PMID: 33293226 DOI: 10.1016/j.saa.2020.119184] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/29/2020] [Accepted: 11/01/2020] [Indexed: 06/12/2023]
Abstract
The CcCR quartic force field (QFF) methodology is capable of computing B0 and C0 rotational constants to within 35 MHz (0.14%) of experiment for triatomic and larger molecules with at least two heavy atoms. Additionally, the same constants for molecules with four or more atoms agree to within 20 MHz (0.12%) of experiment for the current test set. This work also supports previous claims that the same QFF methodology can produce fundamental vibrational frequencies with a deviation less than 5.7 cm-1 from experiment. Consequently, this approach of augmenting complete basis set extrapolated energies with treatments of core electron correlation and scalar relativity produces some of the most accurate rovibrational spectroscopic data available.
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Affiliation(s)
- Mason B Gardner
- Department of Chemistry & Biochemistry, University of Mississippi, University, MS 38677-1848, United States
| | - Brent R Westbrook
- Department of Chemistry & Biochemistry, University of Mississippi, University, MS 38677-1848, United States
| | - Ryan C Fortenberry
- Department of Chemistry & Biochemistry, University of Mississippi, University, MS 38677-1848, United States.
| | - Timothy J Lee
- MS 245-3, NASA Ames Research Center, Moffett Field, CA 94035, United States
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Fortenberry RC, DeYonker NJ. Rovibrational Quantum Chemical Treatment of Inorganic and Organometallic Astrochemicals. Acc Chem Res 2021; 54:271-279. [PMID: 33356121 DOI: 10.1021/acs.accounts.0c00631] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
ConspectusOur two groups have both independently and collaboratively been pushing quantum-chemical techniques to produce highly accurate predictions of anharmonic vibrational frequencies and spectroscopic constants for molecules containing atoms outside of the typical upper p block. Methodologies employ composite approaches, relying on various levels of coupled cluster theory-most often at the singles, doubles, and perturbative triples level-and quartic force field constructions of the potential portion of the intramolecular Watson Hamiltonian. Such methods are known to perform well for organic species, and we have extended this to molecules containing atoms outside of this realm.One notable atom that has received much attention in this application is magnesium. Mg is the second-most-abundant element in the Earth's mantle, and while molecules containing this element are among the confirmed astrochemicals, its further atomic abundance in the galaxy implies that many more molecules (both purely inorganic and organometallic) containing element 12 exist in astrophysical regions in chemical sizes between those of atoms and dust-sized nanocrystals. Our approach discussed herein is producing quality benchmarks and predicting novel data for magnesium-bearing molecules.The story is similar for Al and Si, which are also notably abundant in both rocky bodies and the universe at large. While Na, Sc, and Cu may not be as abundant as Mg, Al, and Si, molecules containing Na and transition metals have also previously been reported to be detected beyond the Earth. Consequently, the need to produce spectral reference data for molecules containing such atoms is growing. While several experimental groups (including, notably, the groups in Arizona, Boston, and France/Spain) have clearly led the way in detection of inorganic/organometallic molecules in space, computational support and even rational design can provide novel avenues for the detection of molecules containing atoms not typically studied in most laboratories. The application of quantum chemistry to other elements beyond carbon and its cronies at the top right of the periodic table promises a better understanding of the observable universe. It will also provide novel and fundamental chemical insights pushing the "central science" into new molecular territory.
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Affiliation(s)
- Ryan C. Fortenberry
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677-1848, United States
| | - Nathan J. DeYonker
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38152, United States
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9
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Burton MA, Cheng Q, Halfen DT, Lane JH, DeYonker NJ, Ziurys LM. The structure of ScC 2 (X̃ 2A 1): A combined Fourier transform microwave/millimeter-wave spectroscopic and computational study. J Chem Phys 2020; 153:034304. [PMID: 32716169 DOI: 10.1063/5.0008746] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Pure rotational spectra of Sc13C2 (X̃2A1) and Sc12C13C (X̃2A') have been measured using Fourier transform microwave/millimeter-wave methods. These molecules were synthesized in a DC discharge from the reaction of scandium vapor, produced via laser ablation, with 13CH4 or 13CH4/12CH4, diluted in argon. The NKa,Kc = 10,1 → 00,0, 20,2 → 10,1, 30,3 → 20,2, and 40,4 → 30,3 transitions in the frequency range of 14 GHz-61 GHz were observed for both species, each exhibiting hyperfine splittings due to the nuclear spins of 13C (I = 1/2) and/or Sc (I = 7/2). These data have been analyzed with an asymmetric top Hamiltonian, and rotational, spin-rotation, and hyperfine parameters have been determined for Sc13C2 and Sc12C13C. In addition, a quartic force field was calculated for ScC2 and its isotopologues using a highly accurate coupled cluster-based composite method, incorporating complete basis set extrapolation, scalar relativistic corrections, outer core and inner core electron correlation, and higher-order valence correlation effects. The agreement between experimental and computed rotational constants, including the effective constant (B + C), is ∼0.5% for all three isotopologues. This remarkable agreement suggests promise in predicting rotational spectra of new transition metal-carbon bearing molecules. In combination with previous work on Sc12C2, an accurate structure for ScC2 has been established using combined experimental (B, C) and theoretical (A) rotational constants. The radical is cyclic (or T-shaped) with r(Sc-C) = 2.048(2) Å, r(C-C) = 1.272(2) Å, and ∠(C-Sc-C) = 36.2(1)°. The experimental and theoretical results also suggest that ScC2 contains a C2 - moiety and is largely ionic.
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Affiliation(s)
- M A Burton
- Department of Chemistry and Biochemistry, Department of Astronomy, Steward Observatory, University of Arizona, 1305 E. 4th Street, Tucson, Arizona 85719, USA
| | - Q Cheng
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38152, USA
| | - D T Halfen
- Department of Chemistry and Biochemistry, Department of Astronomy, Steward Observatory, University of Arizona, 1305 E. 4th Street, Tucson, Arizona 85719, USA
| | - J H Lane
- Department of Chemistry and Biochemistry, Department of Astronomy, Steward Observatory, University of Arizona, 1305 E. 4th Street, Tucson, Arizona 85719, USA
| | - N J DeYonker
- Department of Chemistry, University of Memphis, Memphis, Tennessee 38152, USA
| | - L M Ziurys
- Department of Chemistry and Biochemistry, Department of Astronomy, Steward Observatory, University of Arizona, 1305 E. 4th Street, Tucson, Arizona 85719, USA
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10
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Trabelsi T, Davis MC, Fortenberry RC, Francisco JS. Spectroscopic investigation of [Al,N,C,O] refractory molecules. J Chem Phys 2019; 151:244303. [PMID: 31893878 DOI: 10.1063/1.5125268] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
As of yet, unexamined aluminum bearing molecules may help elucidate aluminum chemistry and associated refractory atom reactions in the interstellar medium. The flexibility of modern quantum chemistry in the construction and analysis of novel molecules makes it perfectly suited to analyze molecules of astrochemical significance. In this paper, high level ab initio electronic structure calculations using the coupled cluster CCSD(T) and explicitly correlated coupled cluster CCSD(T)-F12 methods with large basis sets extrapolated to the complete basis set limit have been performed on the various [Al,N,C,O] isomers. The anharmonic rotational and vibrational spectroscopic parameters for all isomers are produced with these same levels of theory via quartic force fields and vibrational perturbation theory in order to aid in their potential laboratory or even astrophysical identification. The most stable isomer is determined here to be the aluminum isocyanate radical with linear equilibrium geometry AlNCO (X1Σ+). The NCO antisymmetric stretch of AlNCO has an intensity of 1500 km/mol, which should greatly aid in its infrared detection in the region around 2305 cm-1. Additionally, the AlOCN isomer is relatively low lying, possesses a 5.12 D dipole moment, and has a notable kinetic stability, making it a viable candidate for astronomical observation. All isomers are characterized by small frequencies, which indicates that these are floppy molecules. Isomers with a terminal aluminum atom are especially floppy, with bending modes less than 100 cm-1.
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Affiliation(s)
- Tarek Trabelsi
- Department of Earth and Environmental Sciences, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Megan C Davis
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677-1848, USA
| | - Ryan C Fortenberry
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677-1848, USA
| | - Joseph S Francisco
- Department of Earth and Environmental Sciences, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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Mahjoubi K, Mehnen B, Linguerri R, Hochlaf M, Mouhib H. Copper–Chalcogen Bonds in Olfaction: Accurate ab Initio Characterization of CuSH and CuOH. J Phys Chem A 2019; 123:1177-1185. [DOI: 10.1021/acs.jpca.8b10665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. Mahjoubi
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
| | - B. Mehnen
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
| | - R. Linguerri
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
| | - M. Hochlaf
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
| | - H. Mouhib
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
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Trabelsi T, Mahjoubi K, Mehnen B, Hochlaf M, Francisco JS. Spectroscopy and Stability of AlOP: A Possible Progenitor of Interstellar Metal. J Phys Chem A 2019; 123:463-470. [PMID: 30404446 DOI: 10.1021/acs.jpca.8b07843] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Standard and explicitly correlated coupled-cluster theory computations in conjunction with large basis sets are performed to characterize [Al,P,O] isomers. Three isomers, namely, linear-AlOP, bent-AlOP, and linear-OAlP, are found to be stable species. Their optimized equilibrium geometries, harmonic vibrational frequencies, rotational constants, and relative energies are deduced. In addition, a set of spectroscopic parameters is generated from the three-dimensional potential energy surfaces of each isomer at the (R)CCSD(T)/aug-cc-pV5Z level. The linear isomers have an X3Σ- electronic ground state and are characterized as weakly bound systems or floppy molecules due to their low-frequency bending modes (<150 cm-1). The dipole moment of linear-AlOP is calculated to be 1.48 D. By comparison, a much larger dipole moment is computed for linear-OAlP (5.01 D), indicating lower ionic character in AlOP. Both the linear-OAlP and linear-AlOP isomers are suggested to be good candidates for detection in interstellar media by radio astronomy.
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Affiliation(s)
- T Trabelsi
- Department of Earth and Environment Science and Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6243 , United States
| | - K Mahjoubi
- Laboratoire Modélisation et Simulation Multi Echelle , Université Paris-Est, MSME UMR 8208 CNRS , 5 bd Descartes , 77454 Marne-la-Vallée , France
| | - B Mehnen
- Laboratoire Modélisation et Simulation Multi Echelle , Université Paris-Est, MSME UMR 8208 CNRS , 5 bd Descartes , 77454 Marne-la-Vallée , France
| | - M Hochlaf
- Laboratoire Modélisation et Simulation Multi Echelle , Université Paris-Est, MSME UMR 8208 CNRS , 5 bd Descartes , 77454 Marne-la-Vallée , France
| | - J S Francisco
- Department of Earth and Environment Science and Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6243 , United States
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Fortenberry RC, Lee TJ. Computational vibrational spectroscopy for the detection of molecules in space. ANNUAL REPORTS IN COMPUTATIONAL CHEMISTRY 2019. [DOI: 10.1016/bs.arcc.2019.08.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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