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Rusakov YY, Rusakova IL. An efficient method for generating property-energy consistent basis sets. New pecJ- n ( n = 1, 2) basis sets for high-quality calculations of indirect nuclear spin-spin coupling constants involving 1H, 13C, 15N, and 19F nuclei. Phys Chem Chem Phys 2021; 23:14925-14939. [PMID: 34223856 DOI: 10.1039/d1cp01984h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This paper presents a new method of generating property-energy consistent (PEC) basis sets that can be applied to any arbitrary molecular property. The PEC method generates a basis set that is optimized for the molecular property under interest, providing the least possible total molecular energy. The main algorithm of the PEC approach involves Monte Carlo simulations to generate random exponents in the predetermined range. In this work, the PEC method is introduced in the example of generation of new pecJ-n (n = 1, 2) basis sets suited for high-quality correlated calculations of indirect nuclear spin-spin coupling constants involving the most popular NMR-active nuclei: 1H, 13C, 15N, and 19F.
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Affiliation(s)
- Yuriy Yu Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russian Federation.
| | - Irina L Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russian Federation.
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2
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Blechta V, Sýkora J. STRONG INADEQUATE, an experiment for detection of small J(C,C) couplings in symmetrical molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2019; 57:1107-1120. [PMID: 31134675 DOI: 10.1002/mrc.4897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/10/2019] [Accepted: 05/20/2019] [Indexed: 06/09/2023]
Abstract
A new version of the two-dimensional INADEQUATE experiment was designed for detection of small couplings between equivalent carbon atoms separated in the molecule by several bonds, where other techniques fail due to rich line splitting and mutual peak cancellation in many molecules. As the proposed method is suitable for detection of couplings in strongly coupled systems in general, we propose the name STRONG INADEQUATE in the paper. Similar to other methods for detection of couplings between equivalent carbons, the STRONG INADEQUATE experiment utilizes one-bond carbon-proton coupling for creation of the effective chemical shift differences. The STRONG INADEQUATE experiment works superbly for n JCC , where n ≥ 3. Then the F1 pattern is reduced to a simple antiphase doublet with n JCC separation, and this pattern is also preserved when a symmetrical HC···C'H' system is coupled to other protons. Even in the measurement of 2 JCC couplings, the STRONG INADEQUATE experiment generates a much simpler pattern than the original pulse sequences for measurement of couplings between equivalent carbons.
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Affiliation(s)
- Vratislav Blechta
- Department of Analytical Chemistry, Institute of Chemical Process Fundamentals of the CAS, v. v. i., Prague 6, Czech Republic
| | - Jan Sýkora
- Department of Analytical Chemistry, Institute of Chemical Process Fundamentals of the CAS, v. v. i., Prague 6, Czech Republic
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3
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Blechta V, Sýkora J. Proton detection of carbon-carbon couplings in symmetrical molecules: Analytical explanation, SYMONA pulse sequence. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 298:107-114. [PMID: 30544014 DOI: 10.1016/j.jmr.2018.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/26/2018] [Accepted: 12/03/2018] [Indexed: 06/09/2023]
Abstract
The approach to the measurement of one-bond indirect spin-spin coupling constants between equivalent nuclei was revisited. The analytical formulas for development of the density matrix of strongly coupled symmetrical HC-C'H' spin systems were derived and the optimal duration of polarization delay in the original 2QHMBC pulse sequence is discussed. Based on the analytical formulas a new version of a robust indirect detection experiment, called SYMONA (SYmmetrical MOlecules Natural Abundance double-quantum experiment), was proposed for carbon-carbon coupling constants detection in symmetrical molecules. Additionally, application of the SYMONA experiment to more complicated spin systems than isolated HC-C'H' is discussed.
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Affiliation(s)
- Vratislav Blechta
- Institute of Chemical Process Fundamentals of the CAS, v. v. i., Rozvojova 135, 165 02 Prague 6, Czech Republic.
| | - Jan Sýkora
- Institute of Chemical Process Fundamentals of the CAS, v. v. i., Rozvojova 135, 165 02 Prague 6, Czech Republic
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Jokisaari J, Kantola AM, Vaara J. Magnetic field-induced effects on NMR properties. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 281:1-6. [PMID: 28494327 DOI: 10.1016/j.jmr.2017.04.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 04/16/2017] [Indexed: 06/07/2023]
Abstract
In principle, all the NMR observables, spin-spin coupling J, nuclear shielding σ and quadrupole coupling q, are magnetic field-dependent. The field dependence may be classified into two categories: direct and indirect (apparent) dependence. The former arises from the magnetic field-induced deformation of the molecular electronic cloud, while the latter stems from a slightly anisotropic orientation distribution of molecules, due to the interaction between the anisotropy of the molecular susceptibility tensor and the external magnetic field. Here we use 1,3,5-D3-benzene as a model system to investigate the indirect effect on the one-bond 1H-13C and 2H-13C spin-spin couplings (J couplings) and the 2H quadrupole coupling. Experiments carried out at four magnetic fields (4.7, 9.4, 14.1, and 18.8 T) show that the indirect effect is significant already at the magnetic fields commonly used in NMR spectrometers. A joint fit of the data extracted at the different field strengths provides experimental results for the susceptibility anisotropy, 2H quadrupole coupling constant and the related asymmetry parameter, as well as the one-bond CH and CD coupling constants extrapolated to vanishing field strength. The field-induced contributions are found to exceed the commonly assumed error margins of the latter. The data also indicate a primary isotope effect on the one-bond CH coupling constant. There is a tendency to further increase the magnetic field of NMR spectrometers, which leads to more pronounced indirect contributions and eventually significant direct effects as well.
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Affiliation(s)
- J Jokisaari
- University of Oulu, NMR Research Unit, P.O. Box 3000, FI-90014, Finland.
| | - A M Kantola
- University of Oulu, NMR Research Unit, P.O. Box 3000, FI-90014, Finland.
| | - J Vaara
- University of Oulu, NMR Research Unit, P.O. Box 3000, FI-90014, Finland.
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5
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Green TFG, Yates JR. Relativistic nuclear magnetic resonance J-coupling with ultrasoft pseudopotentials and the zeroth-order regular approximation. J Chem Phys 2014; 140:234106. [DOI: 10.1063/1.4882678] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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6
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Weininger U, Respondek M, Löw C, Akke M. Slow Aromatic Ring Flips Detected Despite Near-Degenerate NMR Frequencies of the Exchanging Nuclei. J Phys Chem B 2013; 117:9241-7. [DOI: 10.1021/jp4058065] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ulrich Weininger
- Department of Biophysical Chemistry,
Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Michal Respondek
- Department of Biophysical Chemistry,
Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Christian Löw
- Department of Medical Biochemistry
and Biophysics, Karolinska Institute, SE-171
77 Stockholm, Sweden
| | - Mikael Akke
- Department of Biophysical Chemistry,
Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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Blechta V, Schraml J. Small carbon-carbon couplings in monosubstituted benzenes--their signs and magnitudes determined by HCSE method. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2013; 51:378-381. [PMID: 23592227 DOI: 10.1002/mrc.3954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/19/2013] [Accepted: 03/19/2013] [Indexed: 06/02/2023]
Abstract
Signed values of all intra-ring (2,3,4) J(C,C) couplings in nine monosubstituted benzenes (C6H5-X where X = F, Cl, Br, CH3, OCH3, Si(CH3)3, C≡N, NO, NO2) are experimentally determined as well as nine couplings to substituent carbons. It is confirmed that while all the vicinal intra-ring (3)J(C,C) are positive and all geminal (2)J(C2,C4) are negative, both signs are found for geminal (2)J(C1,C3) couplings. All the determined signs agree with those already predicted by theoretical calculations.
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Affiliation(s)
- Vratislav Blechta
- Institute of Chemical Process Fundamentals of the ASCR, v.v.i., Prague 6, Czech Republic.
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Vähäkangas J, Ikäläinen S, Lantto P, Vaara J. Nuclear magnetic resonance predictions for graphenes: concentric finite models and extrapolation to large systems. Phys Chem Chem Phys 2013; 15:4634-41. [DOI: 10.1039/c3cp44631j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Weininger U, Diehl C, Akke M. ¹³C relaxation experiments for aromatic side chains employing longitudinal- and transverse-relaxation optimized NMR spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2012; 53:181-90. [PMID: 22752933 PMCID: PMC3405241 DOI: 10.1007/s10858-012-9650-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2011] [Accepted: 03/21/2012] [Indexed: 05/21/2023]
Abstract
Aromatic side chains are prevalent in protein binding sites, perform functional roles in enzymatic catalysis, and form an integral part of the hydrophobic core of proteins. Thus, it is of great interest to probe the conformational dynamics of aromatic side chains and its response to biologically relevant events. Indeed, measurements of (13)C relaxation rates in aromatic moieties have a long history in biomolecular NMR, primarily in the context of samples without isotope enrichment that avoid complications due to the strong coupling between neighboring (13)C spins present in uniformly enriched proteins. Recently established protocols for specific (13)C labeling of aromatic side chains enable measurement of (13)C relaxation that can be analyzed in a straightforward manner. Here we present longitudinal- and transverse-relaxation optimized pulse sequences for measuring R (1), R (2), and {(1)H}-(13)C NOE in specifically (13)C-labeled aromatic side chains. The optimized R (1) and R (2) experiments offer an increase in sensitivity of up to 35 % for medium-sized proteins, and increasingly greater gains are expected with increasing molecular weight and higher static magnetic field strengths. Our results highlight the importance of controlling the magnetizations of water and aliphatic protons during the relaxation period in order to obtain accurate relaxation rate measurements and achieve full sensitivity enhancement. We further demonstrate that potential complications due to residual two-bond (13)C-(13)C scalar couplings or dipolar interactions with neighboring (1)H spins do not significantly affect the experiments. The approach presented here should serve as a valuable complement to methods developed for other types of protein side chains.
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Affiliation(s)
- Ulrich Weininger
- Center for Molecular Protein Science, Department of Biophysical Chemistry, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Carl Diehl
- Center for Molecular Protein Science, Department of Biophysical Chemistry, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Mikael Akke
- Center for Molecular Protein Science, Department of Biophysical Chemistry, Lund University, P.O. Box 124, 22100 Lund, Sweden
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Kupka T, Nieradka M, Stachów M, Pluta T, Nowak P, Kjær H, Kongsted J, Kaminsky J. Basis Set Convergence of Indirect Spin–Spin Coupling Constants in the Kohn–Sham Limit for Several Small Molecules. J Phys Chem A 2012; 116:3728-38. [DOI: 10.1021/jp212588h] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Teobald Kupka
- Faculty of Chemistry, University of Opole, 45-052 Opole, Poland
| | | | - Michał Stachów
- Faculty of Chemistry, University of Opole, 45-052 Opole, Poland
| | - Tadeusz Pluta
- Institute of Chemistry, University of Silesia, 40-007 Katowice, Poland
| | - Piotr Nowak
- Technical University of Opole, Opole, Poland
| | - Hanna Kjær
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Jacob Kongsted
- Department of Physics, Chemistry
and Pharmacy, University of Southern Denmark, DK-5230 Odense, Denmark
| | - Jakub Kaminsky
- Institute of Organic Chemistry and Biochemistry, 166 10 Prague, Czech Republic
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11
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Celebre G, De Luca G, Di Pietro ME. Experimental assessment of the vibration-reorientation contribution to liquid crystal NMR dipolar couplings: the case of tetramethylallene dissolved in a nematic mesophase. J Phys Chem B 2011; 115:11119-26. [PMID: 21879737 DOI: 10.1021/jp2021598] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the present paper, the peculiar orientational behavior, studied by liquid crystal NMR (LXNMR) spectroscopy, of the D(2d) symmetry quasi-spherical molecule of tetramethylallene (TMA) dissolved in the nematic solvent I52 is exploited to attempt a quantitative experimental assessment of the correlation between molecular vibrations and overall rotations in weakly oriented molecules. The analysis of the very small D(HH) and (1)D((13)C-H) dipolar couplings, available from the natural abundance LXNMR spectra of TMA at different temperatures, allows for a derivation leading (by making a few approximations) to the quantification of the vibration-reorientation (also called nonrigid) contribution affecting the observed direct (1)D((13)C-H) dipolar coupling. The obtained results show that, under the particular conditions of the studied system (very weak orientational ordering of a highly symmetric molecule), this contribution is particularly important, in order to reproduce the whole value of the "observed" dipolar coupling. This issue is discussed and commented on at length in the work, also, by making reference to the analogy with perfectly symmetric molecules (such as methane and analogues) dissolved in liquid crystalline phases.
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Affiliation(s)
- Giorgio Celebre
- Dipartimento di Chimica, Università della Calabria, v. P. Bucci, I-87036 Rende (CS), Italy.
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12
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Kantola AM, Lantto P, Vaara J, Jokisaari J. Carbon and proton shielding tensors in methyl halides. Phys Chem Chem Phys 2010; 12:2679-92. [DOI: 10.1039/b923506j] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Ikäläinen S, Lantto P, Manninen P, Vaara J. NMR tensors in planar hydrocarbons of increasing size. Phys Chem Chem Phys 2009; 11:11404-14. [DOI: 10.1039/b919860a] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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14
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Witanowski M, Kamieńska-Trela K, Biedrzycka Z, Bechcicka M. Indirect carbon–carbon spin–spin couplings across one, two and three bonds in pyridine and diazine systems: experiment and theory. J PHYS ORG CHEM 2008. [DOI: 10.1002/poc.1276] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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15
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Joyce SA, Yates JR, Pickard CJ, Mauri F. A first principles theory of nuclear magnetic resonance J-coupling in solid-state systems. J Chem Phys 2007; 127:204107. [DOI: 10.1063/1.2801984] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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16
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Witanowski M, Kamieńska-Trela K, Biedrzycka Z. Indirect carbon–carbon couplings across one, two and three bonds in substituted benzenes: Experiment and theory. J Mol Struct 2007. [DOI: 10.1016/j.molstruc.2007.01.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Del Bene JE, Elguero J, Alkorta I, Yañez M, Mó O. An ab initio study of 15N-11B spin-spin coupling constants for borazine and selected derivatives. J Phys Chem A 2007; 110:9959-66. [PMID: 16898700 DOI: 10.1021/jp0628737] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ab initio equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) calculations have been performed to investigate substituent effects on coupling constants for borazine and selected substituted borazines. For molecules in which F atoms are not bonded to adjacent atoms in the ring, F substitution increases the one-bond (11)B-(15)N coupling constants involving the atom at which substitution occurs but leaves the remaining one-bond B-N coupling constants essentially unchanged. For these molecules, the magnitudes of one-bond B-N coupling constants are only slightly dependent on the number of F atoms present. Fluorine substitution at adjacent B and N atoms in the borazine ring further increases the one-bond B-N coupling constant involving the substituted atoms and has the same effect on the other one-bond coupling constants as observed for corresponding molecules in which substitution occurs at alternate sites. In contrast to the effect of F substitution, substitution of Li at either N or B decreases one-bond B-N coupling constants relative to borazine. The effects of F and Li substitution on one-bond B-N coupling constants for borazine are similar to F and Li substitution effects on (13)C-(13)C coupling constants for benzene.
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Affiliation(s)
- Janet E Del Bene
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, Instituto de Química, Médica, CSIC, Juan de la Cierva, 3, E-28006 Madrid, Spain.
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18
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Vaara J. Theory and computation of nuclear magnetic resonance parameters. Phys Chem Chem Phys 2007; 9:5399-418. [PMID: 17925967 DOI: 10.1039/b706135h] [Citation(s) in RCA: 192] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The art of quantum chemical electronic structure calculation has over the last 15 years reached a point where systematic computational studies of magnetic response properties have become a routine procedure for molecular systems. One of their most prominent areas of application are the spectral parameters of nuclear magnetic resonance (NMR) spectroscopy, due to the immense importance of this experimental method in many scientific disciplines. This article attempts to give an overview on the theory and state-of-the-art of the practical computations in the field, in terms of the size of systems that can be treated, the accuracy that can be expected, and the various factors that would influence the agreement of even the most accurate imaginable electronic structure calculation with experiment. These factors include relativistic effects, thermal effects, as well as solvation/environmental influences, where my group has been active. The dependence of the NMR spectra on external magnetic and optical fields is also briefly touched on.
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Affiliation(s)
- Juha Vaara
- Laboratory of Physical Chemistry, Department of Chemistry, FIN-00014, University of Helsinki, Finland.
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Anklin C, Alemany LB. Detailed analysis of coupling constants and isotope effects in NMR spectra of isotopomers of (12)C(68) (13)C(2). MAGNETIC RESONANCE IN CHEMISTRY : MRC 2006; 44:230-40. [PMID: 16477686 DOI: 10.1002/mrc.1749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A preliminary study of the long-range (i.e. two-bond or longer) (13)C--(13)C coupling constants in natural abundance C(70) shows, consistent with recent theoretical calculations by Peralta et al. that the largest long-range J(CC) values for the polar and equatorial sites are clearly smaller than the largest long-range J(CC) values for the other three sites. The unusually large size of the (2)J(CC) couplings between inequivalent carbons in a nonpolar pentagon in C(70) has no analog among (2)J(CC) data reported for planar aromatic compounds. No long-range J(CC) values appear to have been reported for any curved aromatic compounds. In addition, much more precise (1)J(CC) values were obtained for C(70) than was possible about 15 years ago. Comparing the chemical shifts for each of the five isotopomers of C(70) containing only one (13)C nucleus and the frequencies of the satellites for each of the four isotopomers containing two adjacent and inequivalent (13)C nuclei indicates that replacing (12)C with (13)C shields the adjacent (13)C nucleus by 15 to 23 ppb, consistent with the limited (1)Delta(13)C((13/12)C) isotope effect data available on a few small aromatic molecules. Such measurements become possible with natural abundance C(70) only by using a (13)C cryoprobe and a high-field spectrometer (700 MHz). The additional information that could be obtained from a spectrum obtained under ultrahigh resolution conditions is discussed. Secure identification of the singlets arising from the four (12)C(68) (13)C(2) isotopomers with equivalent adjacent (13)C nuclei is necessary to allow the largest long-range J(CC) values to be precisely determined. The presence of numerous isotopomers containing two or more (13)C nuclei would present a great challenge in interpreting the various signals in a spectrum obtained under ultrahigh resolution conditions.
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Affiliation(s)
- Clemens Anklin
- Bruker BioSpin, 15 Fortune Drive, Billerica, Massachusetts 01821, USA
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Claramunt RM, Sanz D, Alkorta I, Elguero J. A theoretical study of multinuclear coupling constants in pyrazoles. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2005; 43:985-91. [PMID: 16142838 DOI: 10.1002/mrc.1671] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The 243 coupling constants of eight N-R-pyrazoles [R=H, CH3, C6H5, COCH3, NH2, NO2, SO2CF3, Si(CH3)3] have been calculated and compared with 131 experimental values. The agreement is good and can be used to estimate new couplings. The whole collection has been statistically analyzed.
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Affiliation(s)
- Rosa M Claramunt
- Departamento de Química Orgánica y Bio-Orgánica, UNED, Facultad de Ciencias, Senda del Rey 9, E-28040 Madrid, Spain
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De Luca G, Longeri M, Pileio G, Lantto P. NMR Spectroscopy Investigation of the Cooperative Nature of the Internal Rotational Motions in Acetophenone. Chemphyschem 2005; 6:2086-98. [PMID: 16208750 DOI: 10.1002/cphc.200500134] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The proton NMR spectrum of the doubly enriched acetophenone-carbonyl,methyl-13C2 isotopomer dissolved in a liquid-crystalline solvent (LXNMR) was analyzed to yield a data set of 19 dipolar couplings. The presence of so many couplings, and in particular the dependence of some of them on the acetyl carbons enabled the investigation of the structure of the acetyl moiety and of possible cooperative motions about the aryl-carbonyl and carbonyl-methyl bonds. Methodological aspects, and approximations relating to the application of the vibrational correction procedure in the presence of large-amplitude torsional motions, are discussed. Results show that it is possible to discriminate between a continuous and a discrete conformer distribution about the angle phi(1) but not among a few proposed continuous shapes of U(iso)({phi}). In this study, the use of dipolar couplings with a non-negligible contribution from the indirect spin-spin coupling tensor J, (D(C8C9) in our case), for structural determination is extended from rigid to flexible molecules. The 1/2J(aniso)(C8C9) contribution was derived theoretically using the density functional theory linear response (DFT-LR) first-principles calculation of the J(C8C9) spin-spin coupling tensor.
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Affiliation(s)
- Giuseppina De Luca
- Universitá della Calabria, Dipartimento di Chimica, Via P. Bucci, 87030 Arcavacata di Rende Cs, Italy
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22
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Investigations of the 1J(13C1H) spin–spin coupling and 13C magnetic shielding of gaseous benzene-13C. J Mol Struct 2005. [DOI: 10.1016/j.molstruc.2004.10.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Theoretical NMR nJ(13C,13C) Scalar Couplings as Probes to Study Diamagnetic Ring Currents in Fullerenes. ADVANCES IN QUANTUM CHEMISTRY 2005. [DOI: 10.1016/s0065-3276(05)48009-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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De Kowalewski DG, Contreras * RH, Díez E, Esteban A. NMRJ(C,C) scalar coupling analysis of the effects of substituents on the keto–enol tautomeric equilibrium in 2-OH-n-X-pyridines. An experimental and DFT study. Mol Phys 2004. [DOI: 10.1080/00268970412331292902] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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25
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de Kowalewski DG, Díez E, Esteban AL, Barone V, Peralta JE, Contreras RH. Substituent effects on scalar J(13C, 13C) couplings in pyrimidines. An experimental and DFT study. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2004; 42:938-943. [PMID: 15386555 DOI: 10.1002/mrc.1426] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
One- two- and three 13C, 13C (n = 1, 2, 3) scalar couplings, (n)J(C,C) in a set of pyrimidine derivatives were studied both experimentally at natural abundance and theoretically by their DFT calculation of all four contributions. Trends of non-contact terms are discussed and substituent effects are rationalized, comparing some of them with the corresponding values in benzene and pyridine. Although substituent effects on non-contact terms are relatively important, the whole trend is dominated by the Fermi contact term. According to the current literature, substituent effects on 1J(C,C) couplings in benzene derivatives are dominated by the inductive effect, which, apparently, is also the case in nitrogen heteroaromatic compounds. However, some differences observed in this work for substituent effects on 1J(C,C) couplings in pyrimidine derivatives suggest that in the latter type of compounds substituent effects can be affected by the orientation of the ring nitrogen lone pairs.
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Affiliation(s)
- Dora G de Kowalewski
- Departamento de Física, FCEyN, Universidad de Buenos Aires, Ciudad Universitaria, P. 1 and CONICET (C1428EHA), Buenos Aires, Argentina
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Forgeron MAM, Gee M, Wasylishen RE. A Theoretical Investigation of One-Bond Phosphorus−Phosphorus Indirect Nuclear Spin−Spin Coupling Tensors, 1J(31P,31P), Using Density Functional Theory. J Phys Chem A 2004. [DOI: 10.1021/jp040034j] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michelle A. M. Forgeron
- Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - Myrlene Gee
- Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - Roderick E. Wasylishen
- Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
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27
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Ruden TA, Lutnæs OB, Helgaker T, Ruud K. Vibrational corrections to indirect nuclear spin–spin coupling constants calculated by density-functional theory. J Chem Phys 2003. [DOI: 10.1063/1.1569846] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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28
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Celebre G, De Luca G, Emsley JW, Foord EK, Longeri M, Lucchesini F, Pileio G. The conformational distribution in diphenylmethane determined by nuclear magnetic resonance spectroscopy of a sample dissolved in a nematic liquid crystalline solvent. J Chem Phys 2003. [DOI: 10.1063/1.1555631] [Citation(s) in RCA: 38] [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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29
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Solvent Effects on the Indirect Spin–Spin Coupling Constants of Benzene: The DFT-PCM Approach. Int J Mol Sci 2003. [DOI: 10.3390/i4030119] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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30
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MOLCHANOV SERGEY, GRYFF-KELLER ADAM. Nuclear spin relaxation and magnetic shielding tensors of atoms constituting cyanogen bromide molecule. Mol Phys 2002. [DOI: 10.1080/00268970210152764] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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31
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Lantto P, Vaara J, Helgaker T. Spin–spin coupling tensors by density-functional linear response theory. J Chem Phys 2002. [DOI: 10.1063/1.1502243] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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32
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Geller JM, Wosnick JH, Butler IS, Gilson DFR, Morin FG, Bélanger-Gariépy F. X-ray diffraction, Raman spectroscopic, and solid-state NMR studies of the group 14 metal-(tetracarbonyl)cobalt complexes Ph3MCo(CO)4 (M = Si, Sn, Pb). CAN J CHEM 2002. [DOI: 10.1139/v02-110] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Single-crystal X-ray diffraction studies illustrate that the three title compounds are isomorphous, belonging to the triclinic space group P[Formula: see text], with slightly distorted trigonal bipyramidal geometry about cobalt. The solid-state 29Si, 119Sn, and 207Pb cross-polarization magic angle spinning (CP MAS) NMR spectra are presented. The indirect spinspin coupling constant (J), quadrupolardipolar shift (d), direct dipolar coupling constant (D' ), anisotropy in spinspin coupling (ΔJ), and the chemical shift tensor were extracted. A plot of the reduced coupling constant vs. s-electron densities at the nucleus indicates that the Fermi contact term may be dominant for the tin and lead complexes; however, the large ΔJ for all complexes indicate that there are also significant anisotropic terms. Trends in the Raman scattering spectra are also discussed.Key words: 29Si, 119Sn, and 207Pb CP MAS NMR, tetracarbonyl cobalt, spinspin coupling, chemical shift tensor, quadrupole coupling, Fermi contact, cobaltgroup 14.
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33
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Syvitski RT, Burnell EE. Dipole-induced ordering in nematic liquid crystals. II. The elusive holy grail. J Chem Phys 2000. [DOI: 10.1063/1.1287336] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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34
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Syvitski RT, Burnell EE. Multiple quantum and high-resolution NMR, molecular structure, and order parameters of partially oriented ortho and meta dimethyl-, dichloro-, and chloromethylbenzenes codissolved in nematic liquid crystals. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2000; 144:58-73. [PMID: 10783274 DOI: 10.1006/jmre.1999.2013] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We develop a strategy for analyzing complex nuclear magnetic resonance (NMR) spectra of several solutes codissolved in liquid-crystal phases. Spectral parameters of solutes m- or o-xylene were estimated by analyzing 2D multiple-quantum NMR spectra using a modified version of a least-squares fitting routine which adjusts chemical shifts, order parameters, structural parameters, and/or dipolar couplings independently. These estimates were used to facilitate analysis of the high-resolution spectra which contain resonances from many solutes. Calculated spectra of m- or o-xylene were subtracted from the experimental high-resolution spectra leaving resonances from the other solutes readily visible. Accurate spectral parameters of all codissolved solutes were determined from the high-resolution spectra. Order parameters and structural parameters (including vibrationally corrected parameters) of m- and o-xylene, m- and o-chlorotoluene, and m- and o-dichlorobenzene were calculated from the dipolar couplings.
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Affiliation(s)
- R T Syvitski
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada.
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35
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Bryce DL, Wasylishen RE. Indirect Nuclear Spin−Spin Coupling Tensors in Diatomic Molecules: A Comparison of Results Obtained by Experiment and First Principles Calculations. J Am Chem Soc 2000. [DOI: 10.1021/ja9942134] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David L. Bryce
- Contribution from the Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada, B3H 4J3
| | - Roderick E. Wasylishen
- Contribution from the Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada, B3H 4J3
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36
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Czernek J, Lang J, Sklenář V. Ab Initio Calculations of Spin−Spin Coupling Constants in Anhydrodeoxythymidines. J Phys Chem A 2000. [DOI: 10.1021/jp9937050] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jiří Czernek
- Laboratory of Biomolecular Structure and Dynamics, Masaryk University, Kotlářská 2, CZ-611 37 Brno, Czech Republic, Institute of Chemical Technology, Laboratory of NMR Spectroscopy, CZ-166 28 Prague 6, Czech Republic, and Charles University, Faculty of Mathematics and Physics, CZ-121 16 Prague 2, Czech Republic
| | - Jan Lang
- Laboratory of Biomolecular Structure and Dynamics, Masaryk University, Kotlářská 2, CZ-611 37 Brno, Czech Republic, Institute of Chemical Technology, Laboratory of NMR Spectroscopy, CZ-166 28 Prague 6, Czech Republic, and Charles University, Faculty of Mathematics and Physics, CZ-121 16 Prague 2, Czech Republic
| | - Vladimír Sklenář
- Laboratory of Biomolecular Structure and Dynamics, Masaryk University, Kotlářská 2, CZ-611 37 Brno, Czech Republic, Institute of Chemical Technology, Laboratory of NMR Spectroscopy, CZ-166 28 Prague 6, Czech Republic, and Charles University, Faculty of Mathematics and Physics, CZ-121 16 Prague 2, Czech Republic
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Kaski J, Lantto P, Rantala TT, Schroderus J, Vaara J, Jokisaari J. Experimental and Theoretical Study of the Spin−Spin Coupling Tensors in Methylsilane. J Phys Chem A 1999. [DOI: 10.1021/jp9920491] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jaakko Kaski
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
| | - Perttu Lantto
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
| | - Tapio T. Rantala
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
| | - Jyrki Schroderus
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
| | - Juha Vaara
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
| | - Jukka Jokisaari
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
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38
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Syvitski RT, Burnell EE. NMR and molecular structure of partially oriented mono and para methyl- and chlorobenzenes dissolved in nematic liquid crystals. CAN J CHEM 1999. [DOI: 10.1139/v99-144] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spectral parameters, order parameters, and structural parameters, including the vibrationally corrected ralpha structure of the partially oriented solutes p-xylene, p-chlorotoluene, p-dichlorobenzene, toluene, and chlorobenzene dissolved in three liquid crystal mixtures, are reported. For samples containing the three solutes p-xylene, p-dichlorobenzene, and 1,3,5-trichlorobenzene, multiple quantum (MQ) nuclear magnetic resonance was used to aid in the analysis of the complex high-resolution spectra of the p-xylene. The high-resolution spectra of 1,3,5-trichlorobenzene and p-dichlorobenzene were easily identified and analyzed once the calculated p-xylene spectrum was subtracted from the experimental one. The methyl groups of p-xylene, p-chlorotoluene, and toluene have similar geometries when the structure is determined from dipolar couplings corrected for harmonic vibrations.Key words: nematic liquid crystal, NMR, molecular structure, order parameter.
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39
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Vaara J, Kaski J, Jokisaari J. Indirect Fluorine Coupling Anisotropies inp-Difluorobenzene: Implications to Orientation and Structure Determination of Fluorinated Liquid Crystals. J Phys Chem A 1999. [DOI: 10.1021/jp991295+] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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40
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Onak T, Jaballas J, Barfield M. Density Functional Theory/Finite Perturbation Theory Calculations of Nuclear Spin−Spin Coupling Constants for Polyhedral Carboranes and Boron Hydrides. J Am Chem Soc 1999. [DOI: 10.1021/ja9841097] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas Onak
- Contribution from the Departments of Chemistry, California State University, Los Angeles, Los Angeles, California 90032, and University of Arizona, Tucson, Arizona 85721
| | - Jojo Jaballas
- Contribution from the Departments of Chemistry, California State University, Los Angeles, Los Angeles, California 90032, and University of Arizona, Tucson, Arizona 85721
| | - Michael Barfield
- Contribution from the Departments of Chemistry, California State University, Los Angeles, Los Angeles, California 90032, and University of Arizona, Tucson, Arizona 85721
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41
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Helgaker T, Jaszuński M, Ruud K. Ab Initio Methods for the Calculation of NMR Shielding and Indirect Spinminus signSpin Coupling Constants. Chem Rev 1999; 99:293-352. [PMID: 11848983 DOI: 10.1021/cr960017t] [Citation(s) in RCA: 1035] [Impact Index Per Article: 41.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Trygve Helgaker
- Department of Chemistry, University of Oslo, Box 1033, Blindern, N-0315 Oslo, Norway
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42
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Ottiger M, Bax A. Determination of Relative N−HN, N−C‘, Cα−C‘, and Cα−Hα Effective Bond Lengths in a Protein by NMR in a Dilute Liquid Crystalline Phase. J Am Chem Soc 1998. [DOI: 10.1021/ja9826791] [Citation(s) in RCA: 200] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marcel Ottiger
- Contribution from the Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520
| | - Ad Bax
- Contribution from the Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520
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43
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Brown EC, Fico RM, Reiter RC, Stevenson CD. Does the Aromatic Dianion of 1,2-Di-13C-[8]annulene Automerize As Does 1,2-Di-13C-benzene? J Org Chem 1998. [DOI: 10.1021/jo9802933] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eric C. Brown
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160
| | - Rosario M. Fico
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160
| | - Richard C. Reiter
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160
| | - Cheryl D. Stevenson
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160
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44
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Kaski J, Lantto P, Vaara J, Jokisaari J. Experimental and Theoretical ab Initio Study of the 13C−13C Spin−Spin Coupling and 1H and 13C Shielding Tensors in Ethane, Ethene, and Ethyne. J Am Chem Soc 1998. [DOI: 10.1021/ja972936m] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jaakko Kaski
- Contribution from the NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland
| | - Perttu Lantto
- Contribution from the NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland
| | - Juha Vaara
- Contribution from the NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland
| | - Jukka Jokisaari
- Contribution from the NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland
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45
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Bernard GM, Wu G, Wasylishen RE. An Experimental and Theoretical Investigation of the Olefinic Carbon Chemical Shift Tensors in trans-Stilbene and Pt(η2-trans-stilbene)(PPh3)2. J Phys Chem A 1998. [DOI: 10.1021/jp980558h] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Guy M. Bernard
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J3
| | - Gang Wu
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J3
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46
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Vaara J, Kaski J, Jokisaari J, Diehl P. NMR Properties of Formamide: A First Principles and Experimental Study. J Phys Chem A 1997. [DOI: 10.1021/jp970287v] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juha Vaara
- NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland, and Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - Jaakko Kaski
- NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland, and Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - Jukka Jokisaari
- NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland, and Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - Peter Diehl
- NMR Research Group, Department of Physical Sciences, University of Oulu, FIN-90571 Oulu, Finland, and Department of Physics, University of Basel, CH-4056 Basel, Switzerland
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47
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Stahl M, Schopfer U, Frenking G, Hoffmann RW. Conformational Analysis with Carbon−Carbon Coupling Constants. A Density Functional and Molecular Mechanics Study. J Org Chem 1997. [DOI: 10.1021/jo970061o] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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