Ab initio studies of AuH, AuCl, HgH and HgCl/sub 2/ using relativistic effective core potentials

Journal Article · Tue Aug 01 00:00:00 EDT 1978 · J. Chem. Phys.; (United States)

OSTI ID:6737999

Hay, P J; Wadt, W R; Kahn, L R; Bobrowicz, F W

Relativistic effective core potentials (ECP) are derived for Au and Hg atoms, where the ECP incorporates the Coulomb and exchange contributions of the core orbitals, the core-orthogonality terms for the valence orthogonality terms for the valence orbitals, and the effect of the ''mass--velocity'' and ''Darwin'' relativistic effects on the valence orbitals. The results of atomic valence-electron (VE) calculations with the ECP's compare favorably with relativistic Hartree--Fock and Dirac--Hartree--Fock calculations and with experiment, when the effects of spin--orbit coupling are included in the VE calculations. Nonrelativistic calculations, by contrast, lead to erroneous predictions and to differences in excitation energies of 1.5--3.5 eV. The large relativistic effects in the atoms carry over into the AuH, AuCl, and HgCl/sub 2/ molecules, as they are important in determining correct bond lengths and bond energies and in influencing the charge distributions. Similarly large relativistic effects are encountered in ionization potentials calculated for HgCl/sub 2/ from orbital energies and from SCF calculations. Spin--orbit coupling is introduced to compare with the experimental photoelectron spectrum. An extensive study of the lowest electronic states of HgH is presented, where the effects of spin--orbit coupling are critical in describing the potential energy curves of the excited /sup 2/Pi/sub 1/2/ and 2/sup 2/..sigma../sup +//sub 1/2/ states.

• Research Organization: Theoretical Division, Los Alamos Scientific Laboratory, University of California, Los Alamos, New Mexico 87545
• OSTI ID: 6737999
• Journal Information: J. Chem. Phys.; (United States), Vol. 69:3
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
GOLD CHLORIDES
ELECTRONIC STRUCTURE
GOLD HYDRIDES
MERCURY CHLORIDES
ATOMIC MODELS
HARTREE-FOCK METHOD
L-S COUPLING
POTENTIAL ENERGY
CHLORIDES
CHLORINE COMPOUNDS
COUPLING
ENERGY
GOLD COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HYDRIDES
HYDROGEN COMPOUNDS
INTERMEDIATE COUPLING
MATHEMATICAL MODELS
MERCURY COMPOUNDS
MERCURY HALIDES
TRANSITION ELEMENT COMPOUNDS
640305* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Theory- (-1987)