Two-component Calculations for the Molecules Containing Superheavy Elements

Young-Kyu Han, Cheolbeom Bae, Sang-Kil Son, and Yoon Sup Lee

[BibTeX]

The quantum mechanical calculations have been actively progressing by many theoretical chemists in the field of superheavy (or transactinide) element chemistry. In the theoretical calculations of electronic structure for such molecules, highly accurate treatments of correlation and relativity are necessary to obtain reliable results. Among many approximate approaches, relativistic effective core potential(RECP) method is probably one of the most successful ones. We have developed two-component Kramers¡¯ restricted Hartree-Fock(KRHF) which includes spin-orbit interactions from the HF level of theory using the RECP. The KRHF code utilizes the RECP with effective one-electron spin-orbit operator at the HF level and produces molecular spinors obeying the double group symmetry. We have implemented second-order Møller-Plesset perturbation, configuration interaction, and coupled-cluster methods based upon the KRHF molecular spinors. The geometry optimization using analytic gradient and normal mode analysis are also possible at the KRHF level for polyatomic molecules. Various dimmers and polyatomic molecules including superheavy elements have been calculated demonstrating that two-component approaches are very promising tools to study superheavy element chemistry.

Tags: superheavy element, spin-orbit effect, ECP, RECP, KAIST