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On the angular dependence of the vicinal fluorine-fluorine coupling constant in 1,2-difluoroethane: deviation from a karplus-like shape
(American Chemical Society, 2006-06)
The angular dependence of the vicinal fluorine−fluorine coupling constant, 3JFF, for 1,2-difluoroethane has been investigated with several polarization propagator methods. 3JFF and its four Ramsey contributions were ...
Vibrational contributions to vicinal proton-proton coupling constants3JHH
(Taylor & Francis Ltd, 2010-03)
Vibrational contributions to the 3JHH couplings of six mono- and five 1,1-di-substituted ethanes, three mono-substituted cyclohexanes, three norbornane-type molecules, and 11 three-membered rings have been calculated at ...
The use of locally dense basis sets in the calculation of indirect nuclear spin–spin coupling constants: The vicinal coupling constants in H3C–CH2X (X=H, F, Cl, Br, I)
(American Institute of Physics, 2000-03)
We have calculated the vicinal indirect nuclear spin-spin coupling constants 3J1H1H3J1H1H in the series of molecules H3C–CH2XH3C–CH2X with X=H, F, Cl, Br, and I at the self-consistent field level and using the second order ...
On the Usage of Locally Dense Basis Sets in the Calculation of NMR Indirect Nuclear Spin–Spin Coupling Constants: Vicinal Fluorine–Fluorine Couplings
(Elsevier Inc, 2005)
Locally dense basis set were developed for correlated ab initio calculations of vicinal fluorine fluorine indirect nuclear spin spin couplings in several saturated and unsaturated fluorinated hydrocarbons. We find that ...
Unblocked statistical-coil tetrapeptides and pentapeptides in aqueous solution: a theoretical study
(Springer, 2002-03)
NMR studies of the molecular conformations of peptides and proteins rely on a comparison of the relevant spectral parameters with the corresponding values for so-called statistical-coilpolypeptides. For this reason, it is ...
Anomeric effect on geminal and vicinal J(HH) NMR coupling constants
(Amer Chemical SocWashingtonEUA, 2004)
Configurational assignments of diastereomeric γ-lactones using vicinal H-H NMR coupling constants and molecular modelling
(American Chemical Society, 2000-08)
The conformational features of four diastereomers of the γ-lactone 2-ethyl-4-methyl-5-oxotetrahydrofuran-3-carboxylic acid were investigated by calculations which included molecular mechanics (MM3), semiempirical (AM1) and ...
Stereochemical dependence of 3J CH coupling constants in 2-substituted 4-t-butyl-cyclohexanone and their alcohol derivatives
(American Chemical Society, 2011-11)
Theoretical and experimental studies on 3J C2H6eq NMR spin - spin coupling constants in both the 2-X-4-t-butyl-cyclohexanone (X = H, CH 3, F, Cl, and Br) and in their alcohol derivatives series are reported. Results thus ...
Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
(American Chemical Society, 2004-06)
The electronic origin of the Karplus-type behavior of vicinal NMR J couplings for H3X−C2H4−XH3, X = C, Sn model compound is analyzed within the framework of the polarization propagator formalism. It is shown that its whole ...
Nmr Spin-spin Coupling Constants: Bond Angle Dependence Of The Sign And Magnitude Of The Vicinal (3)j(hf) Coupling
(Royal Soc ChemistryCambrigde, 2016)