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Bermudez C, Motiyenko RA, Cabezas C, Ilyushin VV, Margulès L, Endo Y, Guillemin JC. Internal rotation analysis of the microwave and millimeter wave spectra of fluoral (CF 3CHO). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 274:121071. [PMID: 35276473 DOI: 10.1016/j.saa.2022.121071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/09/2022] [Accepted: 02/20/2022] [Indexed: 06/14/2023]
Abstract
The rotational spectrum (4-40 GHz and 50-330 GHz) has been measured and analyzed for trifluoroacetaldehyde, also known as fluoral (CF3CHO), which is one of the degradation products of the fluorinated contaminants emitted into the atmosphere. The complexity of the spectroscopic analysis of this molecule arises from the strong coupling between the internal rotation motion of CF3 group and the overall rotation of the molecule. The value obtained for its coupling constant (ρ = 0.91723481(49)) is comparable to the corresponding value of methanol (CH3OH, ρ = 0.81), which is known for its complex spectrum. A total of 12,322 transitions of the ground, the first and second excited torsional states (ΔE1υt = 62.0183(13)cm-1; ΔE2υt = 120.3315(13)cm-1) with J ≤ 50 were included in the analysis that was performed employing the rho-axis-method (RAM), and the RAM36 code. A fit within experimental error (root mean square deviation equals to 35 kHz) has been achieved for this dataset using 47 parameters of the RAM torsion-rotation Hamiltonian. In the course of the analysis, it became evident that for such high ρ value, as it is determined for fluoral, a larger than usual torsional basis set at the first diagonalization step of the two-step diagonalization procedure is required for achieving a fit within experimental error.
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Affiliation(s)
- C Bermudez
- Université de Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers Atomes et Molécules, Lille 59000, France; Grupo de Astrofísica Molecular, Instituto de Física Fundamental (IFF-CSIC), C/ Serrano 121, 28006 Madrid, Spain; Departamento de Química Física y Química Inorgánica, Facultad de Ciencias - I.U. CINQUIMA, Universidad de Valladolid, Paseo de Belén 7, Valladolid 47011, Spain.
| | - R A Motiyenko
- Université de Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers Atomes et Molécules, Lille 59000, France
| | - C Cabezas
- Grupo de Astrofísica Molecular, Instituto de Física Fundamental (IFF-CSIC), C/ Serrano 121, 28006 Madrid, Spain; Department of Applied Chemistry, Science Building II, National Yang Ming Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu 300098, Taiwan
| | - V V Ilyushin
- Institute of Radio Astronomy of NASU, 4 Mystetstv St, Kharkiv 61002, Ukraine; Quantum Radiophysics Department, V.N. Karazin Kharkiv National University, Svobody Square 4, 61022 Kharkiv, Ukraine
| | - L Margulès
- Université de Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers Atomes et Molécules, Lille 59000, France
| | - Y Endo
- Department of Applied Chemistry, Science Building II, National Yang Ming Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu 300098, Taiwan
| | - J-C Guillemin
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France
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Medel R. Simple models for the quick estimation of ground state hydrogen tunneling splittings in alcohols and other compounds. Phys Chem Chem Phys 2021; 23:17591-17605. [PMID: 34369526 DOI: 10.1039/d1cp02115j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Models for the quick estimation of energy splittings caused by coherent tunneling of hydrogen atoms are evaluated with available experimental data for alcohols and improvements are proposed. The discussed models are mathematically simple and require only results from routine quantum chemical computations, i.e. hybrid DFT calculation of the equilibrium geometry and the transition state within the harmonic approximation. A benchmark of experimental splittings spanning four orders of magnitude for 27 alcohol species is captured by three evaluated models with a mean symmetric deviation factor of 1.7, 1.5 and 1.4, respectively, i.e. the calculated values deviate on average by this factor in either direction. Limitations of the models are explored with alcohols featuring uncommon properties, such as an inverted conformational energy sequence, a very light molecular frame, an elevated torsional frequency, or a coupling with a second internal degree of freedom. If the splitting of either the protiated or deuterated form of an alcohol is already experimentally determined, the one of the second isotopolog can be estimated by three additional models with a mean symmetric deviation factor of 1.14, 1.19 and 1.15, respectively. It is shown that this can be achieved with a novel approach without any quantum chemical calculation by directly correlating experimental splittings of isotopologs across related species. This is also demonstrated for other classes of compounds with hydrogen tunneling, such as amines, thiols, and phenols. Furthermore, it is found that the isotope effect can even be anticipated without any further knowledge about the system solely from the size of either splitting with a mean symmetric deviation factor of 1.3. This is based on an extensive sample of 77 pairs of splittings spanning eight orders of magnitude for isotopologs of chemically diverse compounds.
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Affiliation(s)
- Robert Medel
- Institute of Physical Chemistry, University of Goettingen, Tammannstr. 6, 37077 Goettingen, Germany.
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Kobayashi K, Nakamura W, Matsushima T, Tsunekawa S, Ohashi N. Microwave spectroscopy of CD3SH in the first torsionally excited state. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Lees R, Xu LH, Billinghurst B. Patterns in synchrotron near-free-rotor FIR spectra of CH3OH and CD3OH – The tau of methanol. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.127960] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Coudert LH, Zemouli M, Motiyenko RA, Margulès L, Klee S. Analysis of the microwave, terahertz, and far infrared spectra of monodeuterated methanol CH2DOH up to J = 26, K = 11, and o(1). J Chem Phys 2014; 140:064307. [PMID: 24527915 DOI: 10.1063/1.4864203] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The first theoretical approach aimed at accounting for the energy levels of a non-rigid molecule displaying asymmetric-top asymmetric-frame internal rotation is developed. It is applied to a line position analysis of the high-resolution spectrum of the non-rigid CH2DOH molecule and allows us to carry out a global analysis of a data set consisting of already available data and of microwave and far infrared transitions measured in this work. The analysis is restricted to the three lowest lying torsional levels (e0, e1, and o1), to K ⩽ 11, and to J ⩽ 26. For the 8211 fitted lines, the unitless standard deviation is 2.4 and 103 parameters are determined including kinetic energy, hindering potential, and distortion effects parameters.
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Affiliation(s)
- L H Coudert
- Laboratoire Inter-universitaire des Systèmes Atmosphériques, UMR 7583 du CNRS, Universités Paris Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - M Zemouli
- Laboratoire d'Études Physico-Chimiques, Université Dr. T. Moulay de Saïda, Saïda 20000, Algeria
| | - R A Motiyenko
- Laboratoire de Physique des Lasers, Atomes et Molécules, UMR 8523 CNRS - Université Lille I, Bât. P5, 59655 Villeneuve d'Ascq Cedex, France
| | - L Margulès
- Laboratoire de Physique des Lasers, Atomes et Molécules, UMR 8523 CNRS - Université Lille I, Bât. P5, 59655 Villeneuve d'Ascq Cedex, France
| | - S Klee
- Physikalisch-Chemisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen, Germany
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Jansen P, Kleiner I, Meng C, Lees RM, Janssen MH, Ubachs W, Bethlem HL. Prospects for high-resolution microwave spectroscopy of methanol in a Stark-deflected molecular beam. Mol Phys 2013. [DOI: 10.1080/00268976.2013.802819] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Paul Jansen
- a Institute for Lasers, Life and Biophotonics, Department of Physics and Astronomy , VU University Amsterdam , De Boelelaan 1081, 1081 HV, Amsterdam , Netherlands
| | - Isabelle Kleiner
- b Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA) , CNRS UMR 7583 et Universités Paris Diderot et Paris Est , Général de Gaulle, 94010 Créteil Cédex, France
| | - Congsen Meng
- a Institute for Lasers, Life and Biophotonics, Department of Physics and Astronomy , VU University Amsterdam , De Boelelaan 1081, 1081 HV, Amsterdam , Netherlands
| | - Ronald M. Lees
- c Department of Physics and Centre for Laser, Atomic, and Molecular Sciences , University of New Brunswick , Saint John, New Brunswick , E2L 4L5 , Canada
| | - Maurice H.M. Janssen
- a Institute for Lasers, Life and Biophotonics, Department of Physics and Astronomy , VU University Amsterdam , De Boelelaan 1081, 1081 HV, Amsterdam , Netherlands
| | - Wim Ubachs
- a Institute for Lasers, Life and Biophotonics, Department of Physics and Astronomy , VU University Amsterdam , De Boelelaan 1081, 1081 HV, Amsterdam , Netherlands
| | - Hendrick L. Bethlem
- a Institute for Lasers, Life and Biophotonics, Department of Physics and Astronomy , VU University Amsterdam , De Boelelaan 1081, 1081 HV, Amsterdam , Netherlands
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Müller HS, Xu LH, van der Tak F. Investigations into the millimeter and submillimeter-wave spectrum of perdeuterated methanol, CD3OD, in its ground and first excited torsional states. J Mol Struct 2006. [DOI: 10.1016/j.molstruc.2006.02.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wang L, Duan YB, Wang R, Duan G, Mukhopadhyay I, Perry DS, Takagi K. Determination of reduced Hamiltonian parameters for the CD3OH isotopomers of methanol. Chem Phys 2003. [DOI: 10.1016/s0301-0104(03)00251-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Schroderus J, Moazzen-Ahmadi N, Ozier I. The triad in the region of the lowest-frequency parallel fundamental band (v5=1←0) of CH3SiH3: Fermi-type interactions and giant torsional splittings. J Chem Phys 2001. [DOI: 10.1063/1.1377888] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Ilyushin VV, Alekseev EA, Dyubko SF, Podnos SV, Kleiner I, Margulès L, Wlodarczak G, Demaison J, Cosléou J, Maté B, Karyakin EN, Golubiatnikov GY, Fraser GT, Suenram RD, Hougen JT. The Ground and First Excited Torsional States of Acetic Acid. JOURNAL OF MOLECULAR SPECTROSCOPY 2001; 205:286-303. [PMID: 11162216 DOI: 10.1006/jmsp.2000.8270] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A global fit of microwave and millimeter-wave rotational transitions in the ground and first excited torsional states (v(t) = 0 and 1) of acetic acid (CH(3)COOH) is reported, which combines older measurements from the literature with new measurements from Kharkov, Lille, and NIST. The fit uses a model developed initially for acetaldehyde and methanol-type internal rotor molecules. It requires 34 parameters to achieve a unitless weighted standard deviation of 0.84 for a total of 2518 data and includes A- and E-species transitions with J </= 30 and K(a) </= 15. While these results represent a significant improvement over past fitting attempts, it should be cautioned that the present data set is dominated by v(t) = 0 transitions, and no direct infrared measure of the v(t) = 1 <-- 0 torsional interval is available. Copyright 2001 Academic Press.
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Affiliation(s)
- V. V. Ilyushin
- Institute of Radio Astronomy of NASU, Krasnoznamennaya 4, Kharkov, 310002, Ukraine
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Walsh MS, Xu LH, Lees RM, Mukhopadhyay I, Moruzzi G, Winnewisser BP, Albert S, Butler RA, DeLucia FC. Millimeter-Wave Spectra and Global Torsion-Rotation Analysis for the CH(3)OD Isotopomer of Methanol. JOURNAL OF MOLECULAR SPECTROSCOPY 2000; 204:60-71. [PMID: 11034843 DOI: 10.1006/jmsp.2000.8201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
New millimeter-wave and microwave measurements for CH(3)OD have been combined with previous literature data and with an extended body of Fourier transform far-infrared observations in a full global analysis of the first two torsional states (v(t) = 0 and 1) of the ground vibrational state. The fitted CH(3)OD data set contained 564 microwave and millimeter-wave lines and 4664 far-infrared lines, representing the most recent available information in the quantum number ranges J </= 20 and K </= 15. A 53-parameter converged global fit was achieved with an overall weighted standard deviation of 1.060, essentially to within the assigned measurement uncertainties of +/-100 kHz for almost all of the microwave and millimeter-wave lines and +/-6 MHz for the far-infrared lines. The new parameters for CH(3)OD are compared to previous results obtained for the (12)CH(3)OH, (13)CH(3)OH, and CD(3)OH isotopomers over the same quantum number ranges using the identical fitting program. Strong asymmetry-induced coupling between the accidentally near-degenerate 0E and -1E v(t) = 0 substates is successfully modeled by the fit. Copyright 2000 Academic Press.
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Affiliation(s)
- MS Walsh
- Department of Physics, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada
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Xu LH, Lees RM, Hougen JT. On the physical interpretation of torsion-rotation parameters in methanol and acetaldehyde: Comparison of global fit and ab initio results. J Chem Phys 1999. [DOI: 10.1063/1.478272] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Predoi-Cross A, Xu LH, Walsh MS, Lees RM, Winnewisser M, Lichau H. New Measurements and Assignments in the Millimeter-Wave Spectrum of CD3OH. JOURNAL OF MOLECULAR SPECTROSCOPY 1998; 188:94-101. [PMID: 9480806 DOI: 10.1006/jmsp.1997.7504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The ground state rotational spectrum of CD3OH has been revisited in the millimeter-wave range. A total of 216 transition frequencies have been measured and assigned in the 117-179 GHz spectral range, including about 40 transitions previously reported. The spectrum was recorded at the Justus-Liebig University in Giessen, Germany using a frequency modulated millimeter-wave spectrometer. The assignments for the CD3OH transitions were predicted based on energy levels calculated using preliminary results of the global fit of microwave, millimeter-wave, and far-infrared data of Walsh et al. (Paper FC04 presented at the 52nd International Symposium of Molecular Spectroscopy, Columbus, OH, 1997). The new measurements have substantially enlarged the accurate millimeter-wave component of the data set available for the global fit and have allowed Walsh et al. to obtain significant improvement in the CD3OH molecular parameters (J. Mol. Spectrosc. 188, 85-93, 1998). The low residuals between observed and calculated frequencies highlight the quality of the global fit results. Copyright 1998 Academic Press.
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Affiliation(s)
- A Predoi-Cross
- Physics Department, University of Toronto, Toronto, Ontario, M5S 1A7, Canada
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