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Giribet CG. IPPP-CLOPPA Analysis of the Hydrogen Bonds of the Adenine-Thymine Base Pair. Is C-H···O the Third Hydrogen Bond? J Phys Chem A 2024; 128:7568-7580. [PMID: 39190865 DOI: 10.1021/acs.jpca.4c03817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2024]
Abstract
The IPPP-CLOPPA method is applied to investigate the feasibility of the C-H···O moiety as a third hydrogen bond in the adenine-thymine base pair, and the role of this intermolecular contact in its stability. For this purpose, an analysis of the interaction energy and the potential energy of the protons of the "conventional" intermolecular hydrogen bonds and the "unconventional" C-H···O contact is performed, in order to assess how much they contribute to the intermolecular stabilization energy of the base pair. On the same grounds, this study is complemented by the analysis of the molecular electric dipolar polarizability of the hydrogen bond moieties, in order to determine the information that this property can give about the electronic mechanisms that affect the stabilization of the hydrogen bonds, the influence of the π system on each one, and the cooperativity effects among them. The results obtained seem to confirm that the C-H···O moiety contributes to the stability of the adenine-thymine pair almost as much as the "conventional" hydrogen bonds do. Besides, this stabilization effect is strengthened by cooperativity between hydrogen bonds and, particularly and mostly, with the π system.
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Affiliation(s)
- Claudia G Giribet
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, Buenos Aires 1428, Argentina
- CONICET, Universidad de Buenos Aires, Instituto de Física de Buenos Aires (IFIBA), Buenos Aires 1428, Argentina
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Millán LA, Giribet CG, Aucar GA. Polarization propagator theory and the entanglement between MO excitations. Phys Chem Chem Phys 2018; 20:24832-24842. [PMID: 30229764 DOI: 10.1039/c8cp03480j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Entanglement is at the core of quantum physics and so, one may conjecture that it should have some influence on atomic and molecular response properties. The usual way of treating entanglement is by applying information theory via the von Newman entropy. Given that the principal propagator is the operator that contains the physical information that arises due to the transmission of the effects of two external perturbations through the electronic framework of a quantum system, it should have in it the information necessary to quantify the likely entanglement among molecular orbital excitations. In this article we first propose a proper density matrix and from it, the way to quantify entangled excitations by using information theory. The NMR J-couplings are among the best candidates to learn about the potentialities of this formalism. We applied this new tool to analyze the famous Karplus rule and found a relationship between the dihedral angular dependence and the entanglement. We also found that the entangled excitations are related to electron correlation. The new formalism can be applied to all other response properties.
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Affiliation(s)
- Leonardo A Millán
- Institute of Modelling and Innovation on Technology, IMIT CONICET-UNNE, Corrientes, Argentina.
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Giribet CG, Ruiz de Azúa MC. IPPP-CLOPPA Analysis of the Influence of the Methylation on the Potential Energy and the Molecular Polarizability of the Hydrogen Bonds in the Cytosine-Guanine Base Pair. J Phys Chem A 2017; 121:2960-2970. [PMID: 28350166 DOI: 10.1021/acs.jpca.6b10059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The IPPP-CLOPPA method is applied to investigate the influence of a methyl group on the energy of the hydrogen bonds and the potential energy curve of the bridge protons in model compounds, which mimic the methylated and unmethylated cytosine-guanine base pairs. On the same grounds, this influence on the polarizability of the intermolecular hydrogen bonds of these compounds is also addressed, in order to determine whether this linear response property provides a significant proof of the electronic mechanisms that affect the stabilization of the hydrogen bonds. Results obtained show that the methyl electronic system delocalizes on the hydrogen bond region, and changes of these intermolecular hydrogen bonds are due to this effect of delocalization.
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Affiliation(s)
- Claudia G Giribet
- Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires , 1428 Buenos Aires, Argentina.,Instituto de Física de Buenos Aires (IFIBA), CONICET, Universidad de Buenos Aires , 1428 Buenos Aires, Argentina
| | - Martín C Ruiz de Azúa
- Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires , 1428 Buenos Aires, Argentina.,Instituto de Física de Buenos Aires (IFIBA), CONICET, Universidad de Buenos Aires , 1428 Buenos Aires, Argentina
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Giribet CG, Ruiz de Azúa MC. CLOPPA Analysis of the Molecular Polarizability and the Energy of Strong Intramolecular Hydrogen Bonds: Resonance Assisted? J Phys Chem A 2012; 116:12175-83. [DOI: 10.1021/jp309612a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Claudia G. Giribet
- Department
of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, IFIBA-CONICET,
Pab. I, 1428 Buenos Aires, Argentina
| | - Martín C. Ruiz de Azúa
- Department
of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, IFIBA-CONICET,
Pab. I, 1428 Buenos Aires, Argentina
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GUILLEME BJOAQUIN, SAN FABIAN JESUS, DIEZ ERNESTO. Vicinal proton-proton coupling constants V. Couplings to methyl groups. Mol Phys 2010. [DOI: 10.1080/002689797171634] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Giribet CG, Ruiz de Azúa MC. CLOPPA−IPPP Analysis of Cooperative Effects in H-Bonded Molecular Complexes. 2. Application to the Static Molecular Polarizability Tensor. J Phys Chem A 2009; 114:1109-17. [DOI: 10.1021/jp909221a] [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)
- Claudia G. Giribet
- Department of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, Pab. I, (1428) Buenos Aires, Argentina
| | - Martín C. Ruiz de Azúa
- Department of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, Pab. I, (1428) Buenos Aires, Argentina
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Kupka T. Complete basis set prediction of methanol isotropic nuclear magnetic shieldings and indirect nuclear spin-spin coupling constants (SSCC) using polarization-consistent and XZP basis sets and B3LYP and BHandH density functionals. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2009; 47:674-683. [PMID: 19431153 DOI: 10.1002/mrc.2448] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Efficient B3LYP and BHandH density functionals were used to estimate methanol's nuclear magnetic isotropic shieldings and spin-spin coupling constants in the basis set limit. Polarization-consistent pcS-n and pcJ-n (n = 0, 1, 2, 3 and 4), and segmented contracted XZP, where X = D, T, Q and 5, basis sets were used and the results fitted with simple mathematical formulas. The performance of the methods was assessed from comparison with experiment and higher level calculations. 1J(CH) and 3J(HH) values were determined from very diluted solutions in deuterochloroform and compared with theoretical predictions. The agreement between complete basis set (CBS) density functional theory (DFT) predicted isotropic shieldings and spin-spin values and experiment was good. The BHandH/pcS-n methanol shieldings obtained using structures optimized at the same level of theory are approaching the accuracy of the advanced coupled-cluster-singles-doubles-approximate triples (CCSD(T)) calculations.
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Affiliation(s)
- Teobald Kupka
- Department of Chemistry, University of Opole, 45-052 Opole, Poland.
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Zaccari D, Melo JI, Ruiz de Azúa MC, Giribet CG. Relativistic two-component geometric approximation of the electron-positron contribution to magnetic properties in terms of Breit-Pauli spinors. J Chem Phys 2009; 130:084102. [PMID: 19256592 DOI: 10.1063/1.3063639] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
An alternative approach for the calculation of the electron-positron (e-p) contribution to magnetic properties based on two-component Breit-Pauli spinors is presented. In it, the elimination of the small component scheme is applied to the inverse propagator matrix of e-p pairs. The effect of the positronic manifold is expressed as an operator acting on Breit-Pauli spinors. The operator form thus obtained sums up the relativistic correction as a geometric series and as a result a totally different behavior in the vicinity of a nucleus is obtained as compared to the one of the linear response approximation. This feature has deep influence in numerical values of the e-p contribution to the nuclear magnetic shielding of heavy atoms. Numerical calculations carried out for Kr, Xe, and I show that with this approach, the e-p contributions to this property are in good agreement with those of four-component methods.
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Affiliation(s)
- Daniel Zaccari
- Departamento de Fisica, Facultad de Ciencias Exactas, Fisicoquimicas y Naturales, Universidad Nacional de Rio Cuarto, Ruta 36, km 601, 5800 Rio Cuarto, Cordoba, Argentina
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Giribet CG, Azúa MCRD. CLOPPA-IPPP analysis of cooperative effects in hydrogen-bonded molecular complexes. Application to intermolecular 2hJ(N,C) spin-spin coupling constants in linear (CNH)n complexes. J Phys Chem A 2008; 112:4386-93. [PMID: 18410158 DOI: 10.1021/jp712113y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cooperative effects on NMR indirect nuclear coupling constants are analyzed by means of the IPPP-CLOPPA approach (where CLOPPA is the Contributions from Localized Orbitals within the Polarization Propagator Approach and IPPP is the Inner Projections of the Polarization Propagator). The decomposition of the J coupling allows one to classify these effects as those due to changes in the geometric structure and those that directly involve the transmission mechanisms. This latter contribution admits a further classification, taking into account its electronic origin. As an example, the cooperative effects on intermolecular 2hJ(N,C) couplings of the linear complexes (CNH)n (n = 2, 3, 4) are discussed.
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Affiliation(s)
- Claudia G Giribet
- Department of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, Pab. I, (1428) Buenos Aires, Argentina. giribet@ df.uba.ar
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Barfield M. DFT studies of the conformational/structural dependencies of geminal 1H,1H scalar coupling 2J(H,H') in substituted methanes. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45:634-46. [PMID: 17559165 DOI: 10.1002/mrc.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A study is presented of the structural dependencies for scalar, interproton J-coupling across two bonds in a series of substituted methanes. The coupled perturbed, density functional theory method with a B3PW91 functional and aug-cc-pVTZ-J basis sets is used to examine coupling between geminal protons (2)J(H,H') in methane and a series of substituted compounds CH(3)X (X = CH3, CH(2)CH(3), CH=CH2, CH=O, and NH2) as functions of the dihedral angle phi measured about the C1-X2 bonds. All four contributions are obtained but all conformational effects are dominated by the Fermi contact term. Simple linear combination of atomic orbitals (LCAO)-molecular orbital (MO) sum-over-states methods are used to examine the relationships of the coupling constants with dihedral angles as well as internal H-C-H and H-C1-X2 angles. This study explores some novel aspects of geminal H-H coupling including an analysis of the asymmetry in the conformational dependencies arising from non-next-nearest neighbor interactions. For each of the substituted methanes, explicit trigonometric/exponential expressions are given and these accurately reproduce the (2)J(H,H') structural dependencies with standard deviations usually less than 0.03 Hz. The molecular structures for representative bicyclic molecules were fully optimized, and DFT results for (2)J(H,H') reproduce all the trends in the experimental data. A discussion is given on the applicability of the equations for H--H coupling in the substituted methanes to coupling in the bicyclic molecules.
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Affiliation(s)
- Michael Barfield
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA.
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Giribet CG, Ruiz de Azúa MC. The Sign and Magnitude of 2hJ(F,F) and 1hJ(F,H) in FH···FH. A CLOPPA Analysis of Their Distance Dependence. J Phys Chem A 2006; 110:11575-83. [PMID: 17020272 DOI: 10.1021/jp060095c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The sign change of the intermolecular (2h)J(F,F) coupling in the (HF)2 dimer as a function of the F-F distance is discussed by means of the CLOPPA method. It is found that it is due to the competition of positive and negative contributions involving the interaction of the sigma lone pair of the acceptor nucleus with vacant molecular orbitals localized in the F-H...F moiety and with other molecular orbitals localized in the donor molecule. The origin of the sign of each contribution is fully determined by analyzing the response of the electronic system to the magnetic perturbation at the acceptor F nucleus. (2h)J(F,F) coupling in the FH...F-, which is positive for all F-F distances, is also analyzed in order to look for the differences with the former case.
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Affiliation(s)
- Claudia G Giribet
- Department of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, Pab. I, (1428) Buenos Aires, Argentina.
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San-Fabián J, Guilleme J, Díez E, Lazzeretti P, Malagoli M, Zanasi R, Esteban AL, Mora F. Vicinal proton-proton coupling constants. Mol Phys 2006. [DOI: 10.1080/00268979400100664] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Giribet CG, Ruiz de Azúa MC. CLOPPA-IPPP Analysis of Electronic Mechanisms of Intermolecular 1hJ(A,H) and 2hJ(A,D) Spin−Spin Coupling Constants in Systems with D−H···A Hydrogen Bonds. J Phys Chem A 2005; 109:11980-8. [PMID: 16366652 DOI: 10.1021/jp053492g] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electronic origin of intermolecular (2h)J(A,D) and (1h)J(A,H) couplings is discussed by means of the CLOPPA-IPPP approach in several model complexes with D-H...A hydrogen bonds. It is found that the origin of these couplings is mainly due to the interaction between the acceptor sigma lone pair and vacant molecular orbitals localized in the D-H...A moiety, regardless of the donor and acceptor nuclei. The problem of the larger absolute value of (2h)J(A,D) compared to (1h)J(A,H) is also addressed.
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Affiliation(s)
- Claudia G Giribet
- Department of Physics, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Ciudad Universitaria, Pab. I, (1428) Buenos Aires, Argentina.
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Melo JI, Ruiz de Azua MC, Giribet CG, Aucar GA, Provasi PF. Relativistic effects on nuclear magnetic shielding constants in HX and CH3X (X=Br,I) based on the linear response within the elimination of small component approach. J Chem Phys 2004; 121:6798-808. [PMID: 15473737 DOI: 10.1063/1.1787495] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Numerical calculations of relativistic effects on nuclear magnetic shielding constants sigma corresponding to all one-body operators obtained within a formalism developed in previous work were carried out. In this formalism, the elimination of small component scheme is applied to evaluate all quantities entering a four-component RSPT(2) expression of magnetic molecular properties. HX and CH3X (X=Br,I) were taken as model compounds. Calculations were carried out at the Hartree-Fock level for first-order quantities, and at the random-phase approximation (RPA) level for second- and third-order ones. It was found that values of sigma(X) are largely affected by several relativistic corrections not previously considered in the bibliography. sigma Values of the H nucleus are in close agreement with four-component RPA ones. Overall relativistic effects on the shift of sigma(X) from HX to CH3X are smaller than the nonrelativistic shifts.
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Affiliation(s)
- J I Melo
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Cdad. Universitaria, Pab. 1, 1428 Buenos Aires, Argentina
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RUIZ DE AZÚA MC, MELO JI, GIRIBET CG. Orbital contributions to relativistic corrections of the NMR nuclear magnetic shielding tensor originated in scalar field-dependent operators. Mol Phys 2003. [DOI: 10.1080/00268970310001617784] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Electronic Mechanisms of Intra and Intermolecular J Couplings in Systems with C-H···O Interactions. Int J Mol Sci 2003. [DOI: 10.3390/i4040203] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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The Spin–Spin Coupling Constants in Ethane, Methanol and Methylamine: A Comparison of DFT, MCSCF and CCSD Results. Int J Mol Sci 2003. [DOI: 10.3390/i4030143] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Sproviero EM, Burton G. Stereoelectronic Contributions to Long-Range 1H−H Coupling Constants1. J Phys Chem A 2002. [DOI: 10.1021/jp020197c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Eduardo M. Sproviero
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, (C1428EHA) Buenos Aires, Argentina
| | - Gerardo Burton
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, (C1428EHA) Buenos Aires, Argentina
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Vizioli CV, Ruiz De Azua MC. NMR1J(HD) coupling in HD as a function of interatomic distance in the presence of an external magnetic field. Mol Phys 2000. [DOI: 10.1080/00268970050025501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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The nuclear spin–spin coupling constants in methanol and methylamine: geometry and solvent effects. Chem Phys 2000. [DOI: 10.1016/s0301-0104(00)00087-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Guilleme J, Diez E. Vicinal fluorine-proton coupling constants. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1998; 133:255-265. [PMID: 9716466 DOI: 10.1006/jmre.1998.1465] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The angular dependence and the effect of individual substituents upon the NMR vicinal fluorine-proton couplings 3JFH have been studied using data sets of experimental and calculated couplings. Coupling constants for a series of fluoroethane derivatives, CHXF-CH3 and CH2F-CH2X (X = CH3, NH2, OH, and F), were calculated by means of the SCF ab initio and semiempirical INDO/FPT methods. The calculated couplings reproduce correctly the main experimental trends in spite of the limitation in the calculation because of lack of electronic correlation and the use of medium size basis set. The individual substituent effects DeltaKXi<INF POS="STACK">ni are described by quadratic expressions on the relative electronegativities of substituents DeltachiXi (DeltaKXi<INF POS="STACK">ni = k0<INF POS="STACK">ni + kniDeltachiXi + kniiDeltachi2<INF POS="STACK">Xi). A selected data set of 58 experimental couplings, ranging from 1.9 to 44.4 Hz, has been collected from the literature. An extended Karplus equation with 16 coefficients that includes the electronegativity substituent effects has been derived from the experimental data set with a root-mean-square deviation of 1.2 Hz. Copyright 1998 Academic Press.
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Chakraborty D, Chandra P. Ab initio molecular orbital calculations of nuclear spin–spin coupling constants in PH−2, PH3, PH+4 and P2H4. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0166-1280(98)00088-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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25
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Correlated second-order perturbation studies of spin–spin nuclear coupling constants from CS-INDO molecular orbitals: polymethine compounds. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0166-1280(98)00029-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Fabián J, Guilleme J, Diez E. Vicinal carbon-proton coupling constants. Angular dependence and fluorine substituent effects. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0166-1280(97)00313-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Giribet CG, de Az�a MCR, G�mez SB, Botek EL, Contreras RH, Adcock W, Della EW, Krstic AR, Lochert IJ. C3(SINGLE BOND)M? Bond contribution to polarizability tensor and3J(C1M?) NMR coupling constant in 1-X-3-M-bicyclo[1.1.1]pentanes. J Comput Chem 1998. [DOI: 10.1002/(sici)1096-987x(19980130)19:2<181::aid-jcc10>3.0.co;2-l] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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GIRIBET BCLAUDIAG, DOLORES DEMARCO MA, RUIZ DE AZUA MARTINC, CONTRERAS RUBENH. Ab initio ‘CLOPPA’ decomposition of the static molecular polarizability tensor. Mol Phys 1997. [DOI: 10.1080/002689797171797] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Analysis of effect of specific C-H ...X interaction on the direct13C-1H spin-spin coupling constants based onab initio quantum-chemical calculations. Russ Chem Bull 1996. [DOI: 10.1007/bf01434199] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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San Fabián J, Guilleme J. Vicinal fluorine-proton coupling constants. Ab initio calculations of angular dependence and substituent effects. Chem Phys 1996. [DOI: 10.1016/0301-0104(96)00032-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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31
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Harkins PC, Petersson G, Haake P. Distortion of OPO bond angles in phosphorus monoanions: Ab initio studies. J Inorg Biochem 1996. [DOI: 10.1016/0162-0134(95)00031-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Giribet CG, Vizioli CV, de Azúa MCR, Contreras RH, Dannenberg JJ, Masunov A. Proximity effects on nuclear spin–spin coupling constants. Part 2.—The electric field effect on1J(CH) couplings. ACTA ACUST UNITED AC 1996. [DOI: 10.1039/ft9969203029] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Nair AC, Chandra P. Ab initio MO studies of nuclear spin–spin interactions in CH3F, SiH3F and CH3OH. ACTA ACUST UNITED AC 1995. [DOI: 10.1039/ft9959100023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Lazzeretti P, Malagoli M, Zanasi R, Delia EW, Lochert IJ, Giribet CG, de Azúa MCR, Contreras RH. Ab initio and experimental study of NMR coupling constants in bicyclo[1.1.1]pentane. ACTA ACUST UNITED AC 1995. [DOI: 10.1039/ft9959104031] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Vicinal proton—proton coupling constants. Basis set dependence in SCF ab initio calculations. Chem Phys Lett 1993. [DOI: 10.1016/0009-2614(93)85549-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Theoretical ab initio calculation of the indirect nuclear spin-spin coupling constants of monohetero cyclopropanes and cyclopropenes via the equations-of-motion method. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/0022-2364(87)90052-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Lazzeretti P, Rossi E, Zanasi R. First‐order polarization propagator approach to nuclear spin–spin coupling tensors in SiH4 and AlH−4. J Chem Phys 1984. [DOI: 10.1063/1.446446] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Laaksonen A, Kowalewski J, Saunders VR. Finite perturbation MCSCF and CI calculations of nuclear spin-spin coupling constants for some molecules with multiple bonds. Chem Phys 1983. [DOI: 10.1016/0301-0104(83)85275-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Galasso V, Lazzeretti P, Rossi E, Zanasi R. Calculation of the diamagnetic spin‐orbit contribution to the nuclear spin–spin coupling tensors in the water molecule. J Chem Phys 1983. [DOI: 10.1063/1.445955] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lazzeretti P, Zanasi R. Anisotropy of the nuclear spin–spin coupling tensor in water, ammonia, and methane molecules. J Chem Phys 1982. [DOI: 10.1063/1.444114] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lazzeretti P, Rossi E, Taddei F, Zanasi R. Theoretical determination of the nuclear spin–spin coupling tensors in NH−2, NH+4, BH−4molecular ions. J Chem Phys 1982. [DOI: 10.1063/1.444056] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lazzeretti P, Rossi E, Taddei F, Zanasi R. Anisotropy of the nuclear spin coupling in PH−2, PH3, and PH+4molecules. J Chem Phys 1982. [DOI: 10.1063/1.443621] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Prado FR, Giessner-Prettre C, Pullman B. Non-empirical calculations of the nuclear magnetic resonance spectra of imidazole and hydrated imidazole. ACTA ACUST UNITED AC 1981. [DOI: 10.1002/mrc.1270160208] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kowalewski J, Laaksonen A, Saunders VR. Coupled Hartree–Fock and finite perturbation–configuration interaction calculations of nuclear spin–spin coupling constants in the second‐row hydrides. J Chem Phys 1981. [DOI: 10.1063/1.441362] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ribas Prado F, Giessner-Prettre C, Pullman A, Hinton JF, Harpool D, Metz KR. Non empirical quantum mechanical calculations of the1H,13C,15N and17O magnetic shielding constants and of the spin-spin coupling constants in formamide, hydrated formamide and N-methylformamide. ACTA ACUST UNITED AC 1981. [DOI: 10.1007/bf00574436] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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