Theoretical studies on the electronic states of BrOOCl

The electronic states of BrOOCl were investigated using computational approaches. The three forms (trans-, cis-, and twist-forms) of BrOOCl were optimized at the couple-cluster CCSD(T) level of theory with cc-pVTZ basis set. The vertical excitation energies were calculated for the six singlet and two triplet excited states of BrOOCl at the complete active space self-consistent field level of theory and the multi-reference internally contracted configuration interaction level of theory. The scalar relativistic effect on the electronic states of BrOOCl was estimated. The comparison was made for the electronic states of BrOOCl and BrOOBr.