Results 241 to 250 of about 3,070,377 (288)
Some of the next articles are maybe not open access.
Isotope Effects on Nuclear Magnetic Shielding in Molecular Hydrogen
The Journal of Physical Chemistry A, 2018The secondary isotope shifts of six molecular hydrogen isotopologues (H2, D2, T2, HD, HT, and DT) were measured using gas-phase nuclear magnetic resonance spectroscopy. It was found that these isotope shifts are in satisfying agreement with performed ab initio quantum chemistry computations.
Piotr Garbacz, Grzegorz Łach
openaire +2 more sources
Nuclear Magnetic Shielding for Hydrogen in Selected Isolated Molecules
The Journal of Physical Chemistry A, 2012We present the results of gas-phase NMR measurements designed to yield a new experimental value for the absolute (1)H magnetic shielding for an isolated hydrogen molecule and its deuterium isotopomers. The results are based on the original method of direct shielding measurements (Jackowski et al., 2010) and the density dependence of (1)H, (2)H, and (3 ...
Piotr, Garbacz +3 more
openaire +2 more sources
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
openaire +1 more source
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
openaire +2 more sources
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
openaire +2 more sources
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
openaire +2 more sources
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.
openaire +1 more source
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
openaire +3 more sources
A refined treatment of nuclear magnetic shielding
Molecular Physics, 1967化學系 ; 理學院 ...
openaire +1 more source
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.
openaire +1 more source
Nuclear Magnetic Shielding in Fluorine and Hydrogen Compounds
The Journal of Chemical Physics, 1951Measurements of the nuclear magnetic shielding of F19 and H1 are reported for a number of their respective binary covalent compounds. The applied fields required for the F19 and H1 nuclear magnetic resonances, at fixed frequency, vary in these compounds over a range of 3.98 and 0.122 gauss, respectively, at fields of about 6365 gauss.
H. S. Gutowsky, C. J. Hoffman
openaire +1 more source