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Relativistic calculation of nuclear magnetic shieldings of xenon difluoride
The Journal of Chemical Physics, 2006A new method for calculating relativistic nuclear magnetic shieldings at the coupled Hartree-Fock (CHF) level, which is based on the theory of Barysz-Sadlej-Snijders (BSS), was applied to the evaluation of the shieldings in XeF2. Our calculation results were compared with the experimental results for the xenon and fluorine nuclear magnetic shielding ...
K, Kudo, Y, Ootani, M, Funaki, H, Fukui
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How nitrogen modifies the nuclear magnetic shielding in tetraazanaphthalenes
Physical Chemistry Chemical Physics, 2009Although for planar conjugated hydrocarbons the out-of-plane component of proton magnetic shielding is an unquestionable quantitative aromaticity indicator, the same is not true for tetraazanaphthalenes. As in these compounds the (core + sigma)-currents associated to the nitrogen nuclei diminish the perpendicular component of shielding, abnormal values
Inmaculada, García Cuesta +2 more
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The Journal of Chemical Physics, 2005
Two expressions for nuclear-magnetic-shielding tensor components based on analytically differentiating the electronic energy of a system are presented. The first is based on a second-order Douglas-Kroll-Hess approach, in which the off-diagonal block terms of the transformed Dirac Hamiltonian are diminished to second order with respect to both the ...
K, Kudo, H, Fukui
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Two expressions for nuclear-magnetic-shielding tensor components based on analytically differentiating the electronic energy of a system are presented. The first is based on a second-order Douglas-Kroll-Hess approach, in which the off-diagonal block terms of the transformed Dirac Hamiltonian are diminished to second order with respect to both the ...
K, Kudo, H, Fukui
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Electric and magnetic nuclear shielding tensors: A study of the water molecule
Physical Review A, 1986We introduce a series of new linear-response tensors which enable one to estimate the actual electric and magnetic fields at the nuclei of a molecule immersed in an external, spatially uniform, periodical electromagnetic field. The analysis is extended to the case of an electric field gradient.
Paolo Lazzeretti, ZANASI, Riccardo
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Nuclear Magnetic Shielding and Chirality
We investigate particular aspects of chirality and diastereomerism, focusing on how chirality and diastereomerism manifest in the NMR shielding tensor, in particular the antisymmetric components of the tensor. We show that the splitting of diastereomeric nuclear shielding elements serves as acute measures of chirality.Cynthia J. Jameson +2 more
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Correlations in Nuclear Magnetic Shielding, Part II
1976Publisher Summary A quarter of a century has elapsed since Proctor and Yu found “an annoying ambiguity,” in Bloch's phrase in their determination of the magnetic moment of 14N, using an ammonium nitrate solution, and since Ramsey proposed the theory of magnetic screening, based on Van Vleck's theory of magnetic susceptibility.
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On the nuclear magnetic shielding in the hydrogen molecule
Molecular Physics, 1958A simplified method is discussed for calculations of proton shielding in molecules by using wave functions which are constructed from gauge invariant atomic orbitals. The method is applied to the hydrogen molecule by means of a simple lcao mo description. The computed total nuclear shielding constant is 3·2×10−5.
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A refined treatment of nuclear magnetic shielding
Molecular Physics, 1967化學系 ; 理學院 ...
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Nuclear magnetic shielding constants in the CC2 model
Chemical Physics Letters, 1997Abstract Test calculations of nuclear magnetic shielding constants in the CC2 model are performed using the gauge-including atomic orbital approach. Absolute shielding constants are reported for reprsentative first-row hydrides, a few multiply bonded molecules and some challenging cases.
Ove Christiansen +2 more
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Calculations of nuclear magnetic shielding in paramagnetic molecules
The Journal of Chemical Physics, 2003We propose and evaluate first principles methods for calculating the nuclear shielding tensor in open-shell, paramagnetic molecules, dealing with the case of small spin–orbit coupling that, in turn, implies the best applicability to light, organic compounds.
Zilvinas Rinkevicius +3 more
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