Time-dependent four-component relativistic density-functional theory for excitation energies. II. The exchange-correlation kernel.
We extend our previous formulation of time-dependent four-component relativistic density-functional theory [J. Gao, W. Liu, B. Song, and C. Liu, J. Chem. Phys. 121, 6658 (2004)] by using a noncollinear form for the exchange-correlation kernel. The new formalism can deal with excited states involving moment (spin)-flipped configurations which are otherwise not accessible with ordinary exchange-correlation functionals. As a first application, the global potential-energy curves of 16 low-lying omega omega-coupled electronic states of the AuH molecule have been investigated. The derived spectroscopic parameters, including the adiabatic and vertical excitation energies, equilibrium bond lengths, harmonic and anharmonic vibrational constants, fundamental frequencies, and dissociation energies, are grossly in good agreement with those of ab initio multireference second-order perturbation theory and the available experimental data.
Gao
Jun
J
Institute of Theoretical Chemistry, Shandong University, Jinan 250100, People's Republic of China.
Zou
Wenli
W
Liu
Wenjian
W
Xiao
Yunlong
Y
Peng
Daoling
D
Song
Bo
B
Liu
Chengbu
C