Deuteron quadrupole coupling constants

The one-electron properties such as the deuteron quadrupole coupling constant have been less studied until recently, but Dixon et al33 have recently reported the results for this property and also values of the diamagnetic shielding and susceptibility computed with a medium-size basis set. Moderate agreement with experiment was obtained. 

NH4+ has received rather little attention recently. Pople and co-workers studied the geometry with the 4-31G basis set,67 and Hopkinson and Csizmadia58 reported calculations with a (8,3/3) ->[2,1/1] basis. In a rather differently motivated study, basis sets of ca. DZ quality were used by Claxton et al.59 who varied 7 (NH) and the proton exponent in calculations of the deuteron quadrupole coupling constants. These... 

Burnett, L. J. and Muller, B. H. (1971). Deuteron quadrupole coupling constants in three solid deuterated paraffin hydrocarbons C2Dg, C4D1Q, C5D14. J. Chem. Phys. 55 5829. 

EXPERIMENTAL DETERMINATION OF DEUTERON QUADRUPOLE COUPLING CONSTANTS... 

Deuterium has a nuclear spin of unity (/ = 1) and a small nuclear quadrupole moment, Q = 2.7965 X 10"27 cm2.35 In compounds containing deuterium, the molecular environment of the deuterium nucleus usually has a symmetry less than Tnuclear quadrupole moment and the electric field gradient have small values. The reported values of e2qQ/h for deuterium are always less than 400 kHz. 

The general cases of symmetric and asymmetric tops have been reviewed.56 For deuterium, the nuclear quadrupole interaction is small and the hyperfine structure is not always resolved, so that the deuteron quadrupole coupling constant must be obtained by curve-fitting. The accuracy of the data diminishes as the size and the asymmetry of the molecule increases. 

Multireference Cl calculations gave the adiabatic ionization potential Ej = 20.7 eV [30,33] in good agreement with Ej = 20.5 eV from a one-center SCF MO investigation [20]. The deuteron quadrupole coupling constant in PDJ [22], multipole moments, the magnetic susceptibility, and the polarizability of PHJ [12, 21] were calculated by one-center SCF MO procedures. 

R. Ludwig, F. Weinhold, and T. C. Farrar. Experimental and theoretical determination of the temperature dependence of deuteron and oxygen quadrupole coupling constants of liquid water. J. Chem. Phys. 103, 6941-50 (1995). 

Relaxation and self-diffusion techniques in solution are widely used to study hydrogen-bonded systems. The nuclear quadrupole coupling constant (NQCC) presents a sensitive probe for the strength of hydrogen bonding. Unfortunately in the liquid phase this property cannot be measured in a direct way. Two new indirect methods are now presented for determining NQCC in H-bonded liquids. Ferris and Farrar showed that for the OD deuteron of ethanol the DQCC is related to the chemical shift of the hydroxy proton by a linear equation. Thus the straightforward measurement of the chemical shift... 

Fig. 8. H-MAS NMR line shapes with different MAS rates for deuterons undergoing 180° flips at rates indicated. The deuteron quadrupole interaction tensors are taken to be axially symmetric, oriented at 60° to the jump axis with a quadrupole coupling constant of 170 kHz. (Adapted with permission from Ref. 132 http //www.tandf.co.uk/joumals/.)...

Recently, Ernst et al. [106] and Freude et al. [107] suggested the quadrupole coupling constant, Cq, of OD groups in zeoHtes as a scale of acid strength. The electric field gradient at the hydroxyl deuterons studied by NMR spectroscopy... 

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