The multi-reference state-specific coupled-cluster method with a complete-active-space reference (CASCC) developed by our group has been used to calculate the potential energy curves, spectroscopic parameters, and vibrational levels for the ground (X1Σ+) and excited (B1Σ +) states of 19FH. The working algorithm for the CASCC method was derived with a computer-based automated approach that generates the CC energy and amplitude equations and the corresponding coupled-cluster diagrams. The spin-orbital sets for the CASCC calculations have been obtained using the complete-active-space self-consistent-field method (CASSCF). As determined by comparing the theoretical results with experimental ones reconstructed using the Rydberg-Klein-Reese method, the CASCC energies are better than those obtained with the CCSD and EOM-CCSD methods.
ASJC Scopus subject areas
- General Physics and Astronomy
- Physical and Theoretical Chemistry