The prediction of nuclear quadrupole moments from ab initio quantum chemical studies on small molecules. I. The electric field gradients at the 14N and 2H nuclei in N2, NO, NO+, CN, CN−, HCN, HNC, and NH3

1987 ◽  
Vol 86 (12) ◽  
pp. 6908-6917 ◽  
Author(s):  
Peter L. Cummins ◽  
George B. Bacskay ◽  
Noel S. Hush ◽  
Reinhart Ahlrichs
Keyword(s):  
Electric Field ◽  
Small Molecules ◽  
Quantum Chemical ◽  
Quadrupole Moments ◽  
Electric Field Gradients ◽  
Field Gradients ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Nuclear Quadrupole ◽  
Nuclear Quadrupole Moments

The nuclear quadrupole moment of 69Ga and 115In

2009 ◽  
Vol 87 (7) ◽  
pp. 802-805 ◽  
Author(s):  
Hana Yakobi ◽  
Ephraim Eliav ◽  
Uzi Kaldor
Keyword(s):  
Electric Field ◽  
Fock Space ◽  
Coupling Constants ◽  
Basis Sets ◽  
Coupled Cluster ◽  
Quadrupole Moments ◽  
Electric Field Gradients ◽  
Field Gradients ◽  
Nuclear Quadrupole ◽  
Nuclear Quadrupole Moments

Electric field gradients at the nuclei of gallim and indium are determined by finite field calculations of the atomic energies as functions of the nuclear quadrupole moments. The four-component Dirac–Coulomb–Gaunt Hamiltonian serves as framework, and all electrons are correlated by Fock-space coupled cluster with single and double excitations or by single reference coupled cluster with approximate triples. Large, converged basis sets (e.g., 28s24p20d13f5g4h for In) and virtual spaces are used. Together with experimental nuclear quadrupole coupling constants, known with high precision, the calculated electric field gradients yield the nuclear quadrupole moments. For 69Ga, we get Q = 174(3) mb, in agreement with the earlier 171(2) mb obtained from molecular calculations. The 115In moment is Q = 772(5) mb, considerably lower than the previously accepted 810 mb, and in good agreement with the recent molecular value of 770(8) mb.

An ab initio Study of the Molecular Electric-field Gradients of the Chlorsilanes

1996 ◽  
Vol 51 (1-2) ◽  
pp. 41-45
Author(s):  
H. U. Suter ◽  
D. M. Maric ◽  
P. F. Meier
Keyword(s):  
Electric Field ◽  
Ab Initio ◽  
Electron Correlation ◽  
Basis Sets ◽  
Quadrupole Moments ◽  
Electric Field Gradients ◽  
Field Gradients ◽  
Extended Basis ◽  
Good Agreement ◽  
Nuclear Quadrupole Moments

Abstract The electric field gradient (EFG) of chlorine in the chlorine containing silanes (SiCl4 , SiCl3H, SiCl2H2 , and SiClH3) was determined by means of ab initio methods and compared to recent experiments from which nuclear quadrupole moments are extracted. A careful estimation of the AO basis sets and the effect of the electron correlation is undertaken. The results showed the importance of the use of extended basis sets in the calculation of EFGs in second row atoms. Good agreement with deviations less than 5% from the experiments was found. The effect of the electron correlation was found to be small.

The Nuclear Quadrupole Moments of the 20 First Elements: High-Precision Calculations on Atoms and Small Molecules

1992 ◽  
Vol 47 (1-2) ◽  
pp. 189-196 ◽  
Author(s):  
Pekka Pyykkö
Keyword(s):  
Numerical Methods ◽  
Quantum Chemistry ◽  
Small Molecules ◽  
High Precision ◽  
Quantum Chemical ◽  
Coulomb Scattering ◽  
Quadrupole Moments ◽  
Recent Advances ◽  
Nuclear Quadrupole ◽  
Nuclear Quadrupole Moments

AbstractThe available values of the nuclear quadrupole moments for the elements H - Ca are reviewed and related to recent advances in numerical methods in quantum chemistry. For Li the quantum chemical and nuclear Coulomb scattering values now agree. For Mg, also the muonic result agrees with them. For Na and Al, the new, accurate atomic values deviate from the earlier muonic values

Sign in / Sign up

Export Citation Format

Share Document