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Jessen LM, Sauer SPA. On the performance of HRPA(D) for NMR spin-spin coupling constants: Smaller molecules, aromatic and fluoroaromatic compounds. J Chem Phys 2024; 160:064102. [PMID: 38341775 DOI: 10.1063/5.0189932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/15/2024] [Indexed: 02/13/2024] Open
Abstract
In this study, the performance of the doubles-corrected higher random-phase approximation [HRPA(D)] has been investigated in calculations of nuclear magnetic resonance spin-spin coupling constants (SSCCs) for 58 molecules with the experimental values used as the reference values. HRPA(D) is an approximation to the second-order polarization propagator approximation (SOPPA) and is, therefore, computationally less expensive than SOPPA. HRPA(D) performs comparable and sometimes even better than SOPPA, and therefore, when calculating SSCCs, it should be considered as an alternative to SOPPA. Furthermore, it was investigated whether a coupled-cluster singles, doubles and perturbative triples [CCSD(T)] or Møller-Plesset second order (MP2) geometry optimization was optimal for a SOPPA and a HRPA(D) SSCC calculation for eight smaller molecules. CCSD(T) is the optimal geometry optimization for the SOPPA calculation, and MP2 was optimal for HRPA(D) SSCC calculations.
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Affiliation(s)
- Louise Møller Jessen
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark
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Gleeson R, Aggelund PA, Østergaard FC, Schaltz KF, Sauer SPA. Exploring Alternate Methods for the Calculation of High-Level Vibrational Corrections of NMR Spin-Spin Coupling Constants. J Chem Theory Comput 2024. [PMID: 38299500 DOI: 10.1021/acs.jctc.3c01223] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
Traditional nuclear magnetic resonance (NMR) calculations typically treat systems with a Born-Oppenheimer-derived electronic wave function that is solved for a fixed nuclear geometry. One can numerically account for this neglected nuclear motion by averaging over property values for all nuclear geometries with a vibrational wave function and adding this expectation value as a correction to an equilibrium geometry property value. Presented are benchmark coupled-cluster singles and doubles (CCSD) vibrational corrections to spin-spin coupling constants (SSCCs) computed at the level of vibrational second-order perturbation theory (VPT2) using the vibrational averaging driver of the CFOUR program. As CCSD calculations of vibrational corrections are very costly, cheaper electronic structure methods are explored via a newly developed Python vibrational averaging program within the Dalton Project. Namely, results obtained with the second-order polarization propagator approximation (SOPPA) and density functional theory (DFT) with the B3LYP and PBE0 exchange-correlation functionals are compared to the benchmark CCSD//CCSD(T) and experimental values. CCSD//CCSD(T) corrections are also combined with literature CC3 equilibrium geometry values to form the highest-order vibrationally corrected values available (i.e., CC3//CCSD(T) + CCSD//CCSD(T)). CCSD//CCSD(T) statistics showed favorable statistics in comparison to experimental values, albeit at an unfavorably high computational cost. A cheaper CCSD//CCSD(T) + B3LYP method showed quite similar mean absolute deviation (MAD) values as CCSD//CCSD(T), concluding that CCSD//CCSD(T) + B3LYP is optimal in terms of cost and accuracy. With reference to experimental values, a vibrational correction was not worth the cost for all of the other methods tested. Finally, deviation statistics showed that CC3//CCSD(T) + CCSD//CCSD(T) vibrational-corrected equilibrium values deteriorated in comparison to CCSD//CCSD(T) attributed to the use of a smaller basis set or lack of solvation effects for the CC3 equilibrium calculations.
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Affiliation(s)
- Ronan Gleeson
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Patrick A Aggelund
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark
| | | | - Kasper F Schaltz
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark
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Ukhanev SA, Fedorov SV, Rusakov YY, Rusakova IL, Krivdin LB. Computational protocols for the 19F NMR parameters. Part 2: Fluorobenzenes. J Fluor Chem 2023. [DOI: 10.1016/j.jfluchem.2023.110093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Krivdin LB. Theoretical calculations of carbon-hydrogen spin-spin coupling constants. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 108:17-73. [PMID: 30538048 DOI: 10.1016/j.pnmrs.2018.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/09/2018] [Accepted: 10/11/2018] [Indexed: 06/09/2023]
Abstract
Structural applications of theoretical calculations of carbon-hydrogen spin-spin coupling constants are reviewed covering papers published mainly during the last 10-15 years with a special emphasis on the most notable studies of hybridization, substitution and stereoelectronic effects together with the investigation of hydrogen bonding and intermolecular interactions. The wide scope of different applications of calculated carbon-hydrogen couplings in the structural elucidation of particular classes of organic and bioorganic molecules is reviewed, concentrating mainly on saturated, unsaturated, aromatic and heteroaromatic compounds and their functional derivatives, as well as on natural compounds and carbohydrates. The review is dedicated to Professor Emeritus Michael Barfield in view of his invaluable pioneering contribution to this field.
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Affiliation(s)
- Leonid B Krivdin
- A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia.
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Caputo MC, Alkorta I, Provasi PF, Sauer SPA. Analysis of the interactions in FCCF:(H 2O) and FCCF:(H 2O) 2 complexes through the study of their indirect spin–spin coupling constants. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1488006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- María Cristina Caputo
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires y IFIBA – CONICET-UBA, Ciudad Universitaria, Buenos Aires, Argentina
| | - Ibon Alkorta
- Instituto de Química Médica (C.S.I.C.), Madrid, Spain
| | - Patricio F. Provasi
- Department of Physics – IMIT – CONICET, Northeastern University, Corrientes, Argentina
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Faber R, Sauer SPA, Gauss J. Importance of Triples Contributions to NMR Spin-Spin Coupling Constants Computed at the CC3 and CCSDT Levels. J Chem Theory Comput 2017; 13:696-709. [PMID: 27992184 DOI: 10.1021/acs.jctc.6b01003] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present the first analytical implementation of CC3 second derivatives using the spin-unrestricted approach. This allows, for the first time, the calculation of nuclear spin-spin coupling constants (SSCC) relevant to NMR spectroscopy at the CC3 level of theory in a fully analytical manner. CC3 results for the SSCCs of a number of small molecules and their fluorine substituted derivatives are compared with the corresponding coupled cluster singles and doubles (CCSD) results obtained using specialized basis sets. For one-bond couplings the change when going from CCSD to CC3 is typically 1-3%, but much higher corrections were found for 1JCN in FCN, 15.7%, and 1JOF in OF2, 6.4%. The changes vary significantly in the case of multibond couplings, with differences of up to 10%, and even 13.6% for 3JFH in fluoroacetylene. Calculations at the coupled cluster singles, doubles, and triples (CCSDT) level indicate that the most important contributions arising from connected triple excitations in the coupled cluster expansion are accounted for at the CC3 level. Thus, we believe that the CC3 method will become the standard approach for the calculation of reference values of nuclear spin-spin coupling constants.
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Affiliation(s)
- Rasmus Faber
- Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Jürgen Gauss
- Institut für Physikalische Chemie, Universität Mainz , 55099 Mainz, Germany
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Affiliation(s)
| | - J. San Fabián
- Departamento de Química Física Aplicada, Universidad Autónoma de Madrid, Madrid, Spain
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Ghosh A, Chaudhuri P. NMR spin–spin coupling constants in microhydrated ortho-aminobenzoic acid. Mol Phys 2015. [DOI: 10.1080/00268976.2014.955065] [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]
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da Silva AM, Ghosh A, Chaudhuri P. Effect of Hydrogen Bond Formation on the NMR Properties of Glycine–HCN Complexes. J Phys Chem A 2013; 117:10274-85. [DOI: 10.1021/jp4056818] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Arnaldo Machado da Silva
- Departamento
de Física, Universidade Federal do Amazonas, 69077-000 Manaus, AM, Brazil
- Departamento
de Física, Universidade Federal de São Carlos, São Paulo 13565-905, Brazil
| | - Angsula Ghosh
- Departamento
de Física, Universidade Federal do Amazonas, 69077-000 Manaus, AM, Brazil
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Provasi PF, Caputo MC, Sauer SP, Alkorta I, Elguero J. Analysis of the interactions between difluoroacetylene and one or two hydrogen fluoride molecules based on calculated spin–spin coupling constants. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2012.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Faber R, Sauer SPA. On the discrepancy between theory and experiment for the F–F spin–spin coupling constant of difluoroethyne. Phys Chem Chem Phys 2012; 14:16440-7. [DOI: 10.1039/c2cp42198d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Del Bene JE, Alkorta I, Elguero J. Structures, energies, and spin-spin coupling constants of fluoro-substituted 1,3-diborata-2,4-diphosphoniocyclobutanes: four-member B-P-B-P rings B2P2F(n)H(8-n) with n = 0, 1, 2, 4. J Phys Chem A 2011; 115:4511-20. [PMID: 21456565 DOI: 10.1021/jp200535g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An ab initio study has been carried out to determine the structures, relative stabilities, and spin-spin coupling constants of a set of 15 fluoro-substituted 1,3-diborata-2,4-diphosphoniocyclobutanes B(2)P(2)F(n)H(8-n), for n = 0, 1, 2, 4, with four-member B-P-B-P rings. Except for B(2)P(2)F(4)H(4) with four fluorines bonded to two borons, these rings are puckered in a butterfly conformation. For a fixed number of fluorines, the isomers with B-F bonds are significantly more stable than those with P-F bonds. As the number of fluorines increases, the energy difference between the most stable isomer and the other isomers increases. Transition structures which interconvert axial and equatorial positions present relatively small inversion barriers. Coupling constants involving (31)P, namely, (1)J(B-P), (1)J(P-F), (2)J(P-P), (2)J(P-F), and (3)J(P-F) are large and are capable of providing structural information. They are sensitive to the number of fluorines present and can discriminate between axial, equatorial, and geminal B-F and P-F bonds, although not all do this to the same extent. (1)J(B-P) and (2)J(P-P) are similar in equilibrium and transition structures. Although transition structures no longer discriminate between axial and equatorial bonds, (1)J(P-F) and (3)J(P-F) remain sensitive to the number of fluorine atoms present.
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Affiliation(s)
- Janet E Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, United States.
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Vilcachagua JD, Ducati LC, Rittner R, Contreras RH, Tormena CF. Experimental, SOPPA(CCSD), and DFT Analysis of Substitutent Effects on NMR 1JCF Coupling Constants in Fluorobenzene Derivatives. J Phys Chem A 2011; 115:1272-9. [PMID: 21280628 DOI: 10.1021/jp110290b] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Lucas C. Ducati
- Chemistry Institute, State University of Campinas, Caixa Postal 6154, 13084-971 Campinas, SP, Brazil
| | - Roberto Rittner
- Chemistry Institute, State University of Campinas, Caixa Postal 6154, 13084-971 Campinas, SP, Brazil
| | - Rubén H. Contreras
- Department of Physics, FCEyN, University of Buenos Aires and IFIBA-CONICET, Buenos Aires, Argentina
| | - Cláudio F. Tormena
- Chemistry Institute, State University of Campinas, Caixa Postal 6154, 13084-971 Campinas, SP, Brazil
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Del Bene JE, Alkorta I, Elguero J, Mó O, Yáñez M. Structural and Electronic Effects on One-Bond Spin−Spin Coupling Constants 1J(B−N), 1J(B−H), and 1J(B−F) for Complexes of Nitrogen Bases with BH3 and Its Fluoro-Substituted Derivatives. J Phys Chem A 2010; 114:12775-9. [DOI: 10.1021/jp1085747] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Janet E. Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, United States, Instituto de Química Médica (CSIC), Juan de la Cierva, 3, E-28006 Madrid, Spain, and Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, E-28049 Madrid, Spain
| | - Ibon Alkorta
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, United States, Instituto de Química Médica (CSIC), Juan de la Cierva, 3, E-28006 Madrid, Spain, and Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, E-28049 Madrid, Spain
| | - José Elguero
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, United States, Instituto de Química Médica (CSIC), Juan de la Cierva, 3, E-28006 Madrid, Spain, and Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, E-28049 Madrid, Spain
| | - Otilia Mó
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, United States, Instituto de Química Médica (CSIC), Juan de la Cierva, 3, E-28006 Madrid, Spain, and Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, E-28049 Madrid, Spain
| | - Manuel Yáñez
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, United States, Instituto de Química Médica (CSIC), Juan de la Cierva, 3, E-28006 Madrid, Spain, and Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, E-28049 Madrid, Spain
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Del Bene JE, Alkorta I, Elguero J. Do corresponding coupling constants in hydrogen-bonded homo- and hetero-chiral dimers differ? CAN J CHEM 2010. [DOI: 10.1139/v09-177] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ab initio equation-of-motion coupled cluster singles and doubles (EOM–CCSD) calculations have been carried out to evaluate spin–spin coupling constants in six pairs of homo- and hetero-chiral dimers: (HOOH)2, (H2NNH2)2, (FOOH)2, (FHNNH2)2, (HOOOH)2, and (FOOOH)2. Corresponding spin–spin coupling constants in these isomeric pairs of C2 and Ci symmetry may differ, but these differences are small and may not be detectable experimentally. For the complexes with O1–H···O and O1–H···F hydrogen bonds, 1J(O1–H) has a larger absolute value in the C2 isomer. For the same set of complexes, 1J(O1–O2) has a larger absolute value in the Ci isomer. No distinguishable patterns could be discerned in the remaining spin–spin coupling constants in the C2 and Ci isomers of these complexes, nor in complexes with N–H···N hydrogen bonds.
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Affiliation(s)
- Janet E. Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA
- Instituto de Química Médica, CSIC (Consejo Superior de Investigaciones Científicas), Juan de la Cierva, 3, E-28006 Madrid, Spain
| | - Ibon Alkorta
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA
- Instituto de Química Médica, CSIC (Consejo Superior de Investigaciones Científicas), Juan de la Cierva, 3, E-28006 Madrid, Spain
| | - José Elguero
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA
- Instituto de Química Médica, CSIC (Consejo Superior de Investigaciones Científicas), Juan de la Cierva, 3, E-28006 Madrid, Spain
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Del Bene JE, Alkorta I, Elguero J. Two-, three-, and four-bond N–F spin–spin coupling constants in fluoroazines. Mol Phys 2010. [DOI: 10.1080/00268971003692018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Del Bene JE, Alkorta I, Elguero J. Ab initio EOM-CCSD investigation of one-bond C-C, N-C, and N-N spin-spin coupling constants in fluoroazines. J Phys Chem A 2010; 114:5205-10. [PMID: 20353184 DOI: 10.1021/jp100649k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ab initio EOM-CCSD calculations were carried out to examine one-bond (1)J (C-C), (1)J(N-C), and (1)J(N-N) spin-spin coupling constants in benzene, pyridine, the diazines, and selected triazines, tetrazines, and pentazine and their fluoro-substituted derivatives. Relative to benzene, (1)J(C-C) decreases in the azines as N atoms are introduced into the ring, but this decrease does not exceed 5 Hz. In the fluoro-substituted derivatives, (1)J(C-C) may increase only slightly if the coupled carbon atoms form C-H bonds, or increase dramatically if either or both of the coupled atoms participate in C-F bonds. The value of (1)J(C-C) also depends on the nature of the bonding of the coupled atoms in the ring. The largest increase is found when both carbons participate in C-F bonds, and both are ortho to N atoms. Relative to pyridine, (1)J(N-C) increases as N atoms are introduced into the ring, with the magnitude of the increase depending on the bonding of the coupled atoms. It is negligible if neither atom is bonded to another N, increases if one of the coupled atoms is bonded to another N atom, and increases further if both are bonded to other N atoms. Fluoro-substitution has an opposing effect on (1)J(N-C), making this coupling constant less positive or negative when the coupled C participates in a C-F bond. The decrease in (1)J(N-C) relative to the parent molecule is enhanced if either of the coupled atoms is bonded to another N atom or to another C-F group. A further enhancement occurs if both coupled atoms are so bonded, with the largest increases associated with the bonding scheme in which the coupled C is bonded to another N and the coupled N to another C-F. Fluoro-substitution has a small effect on (1)J(N-C) if the coupled C forms a C-H bond, and on (1)J(N-N). Thus, the effects of fluoro-substitution on one-bond couplings tend to be localized.
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Affiliation(s)
- Janet E Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA.
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Del Bene JE, Alkorta I, Elguero J. Probing (1)J(C-F) and (n)J(F-F) spin-spin coupling constants for fluoroazines: an ab initio theoretical investigation. J Phys Chem A 2010; 114:2637-43. [PMID: 20112975 DOI: 10.1021/jp910040w] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ab initio equation-of-motion coupled cluster singles and doubles calculations have been carried out to evaluate one-bond C-F coupling constants (1)J(C-F) and three-, four-, and five-bond F-F coupling constants (n)J(F-F) for a series of mono-, di-, and trifluoroazines. The computed (1)J(C-F) and (n)J(F-F) values for these are in good agreement with available experimental coupling constants. The values of (1)J(C-F) vary as the number and positions of N atoms and the number and relative positions of C-F bonds change, but it is difficult to discern general patterns for these changes due to opposing effects of the Fermi contact and paramagnetic spin-orbit terms. The majority of (1)J(C-F) values lie in a range that includes the three monosubstituted pyridines. For trifluoroazines, (1)J(C-F) for a C-F bond that is ortho to two other C-F bonds is greater than (1)J(C-F) for the other two bonds. F-F coupling constants arise in these molecules when the two C-F bonds are ortho, meta, or para. Values of (3)J(F-F) are relatively large and negative, whereas values of (5)J(F-F) are relatively large and positive. (4)J(F-F) may be positive or negative and large or small. The value of this coupling constant depends on the nature of the atom that links the two C-F bonds and the number and positions of N atoms in the ring. The calculations carried out in this study at a reliable level of theory give values for one-bond C-F and n-bond F-F spin-spin coupling constants for the fluoroazines that are not available experimentally. In addition, the patterns that describe the changes that occur in these molecules provide a basis for predicting their values in larger, related systems in the absence of experimental data and direct calculations.
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Affiliation(s)
- Janet E Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA.
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Del Bene JE, Alkorta I, Elguero J. Ab Initio Study of Nonadditivity Effects: Spin−Spin Coupling Constants for Tetrafluoroethene in Ternary π Complexes. J Phys Chem A 2010; 114:3713-7. [DOI: 10.1021/jp1003159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Janet E. Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, and Instituto de Química Médica (CSIC), Juan de la Cierva, 3; 28006-Madrid (Spain)
| | - Ibon Alkorta
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, and Instituto de Química Médica (CSIC), Juan de la Cierva, 3; 28006-Madrid (Spain)
| | - José Elguero
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, and Instituto de Química Médica (CSIC), Juan de la Cierva, 3; 28006-Madrid (Spain)
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Alkorta I, Blanco F, Del Bene JE, Elguero J, Hernández-Folgado L, Jimeno ML. Difluorobenzenes revisited: an experimental and theoretical study of spin-spin coupling constants for 1,2-, 1,3-, and 1,4-difluorobenzene. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2010; 48:68-73. [PMID: 19941318 DOI: 10.1002/mrc.2543] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The experimental spin-spin coupling constants (SSCCs) for 1,3- and 1,4-difluorobenzene have been determined anew, and found to be consistent with previously determined values. SSCCs for 1,2-, 1,3-, and 1,4-difluorobenzene have been analyzed by comparing them with the coupling constants computed using the second-order polarization propagator approximation (SOPPA) and the equation-of-motion coupled cluster singles and doubles method (EOM-CCSD). Eighty experimental values have been analyzed using SOPPA calculations, and a subset of 40 values using both SOPPA and EOM-CCSD approaches. One-bond coupling constants (1)J(C-C) and (1)J(C-F) are better described by EOM-CCSD, whereas one-bond (1)J(C-H) values are better described by SOPPA. An empirical equation is presented which allows for the prediction of unknown coupling constants from computed SOPPA values. A similar approach may prove useful for predicting coupling constants in larger systems.
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Affiliation(s)
- Ibon Alkorta
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, E-28006 Madrid, Spain.
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Del Bene JE, Alkorta I, Elguero J. Systematic Comparison of Second-Order Polarization Propagator Approximation (SOPPA) and Equation-of-Motion Coupled Cluster Singles and Doubles (EOM-CCSD) Spin−Spin Coupling Constants for Molecules with C, N, and O Double and Triple Bonds and Selected F-Substituted Derivatives. J Chem Theory Comput 2008; 5:208-16. [DOI: 10.1021/ct800321b] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Janet E. Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, and Instituto de Química Médica, CSIC, Juan de la Cierva, 3, E-28006 Madrid, Spain
| | - Ibon Alkorta
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, and Instituto de Química Médica, CSIC, Juan de la Cierva, 3, E-28006 Madrid, Spain
| | - José Elguero
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, and Instituto de Química Médica, CSIC, Juan de la Cierva, 3, E-28006 Madrid, Spain
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