First-order excited state properties in the four-component Hartree-Fock approximation: The excited state electric dipole moments in CsAg and CsAu.

An implementation of the second-order residue of the quadratic response function is presented in the four-component Hartree-Fock approximation, and the calculation of first-order properties of electronically excited states can thereby be achieved. Results are presented for the excited state electric dipole moments of the valence excited states in CsAg and CsAu. For CsAg, and even more so for CsAu, nonscalar relativistic effects on this property may be substantial, e.g., at the four-component level of theory, the excited-to-ground state dipole moment difference Δμ ranges from 1.994 to 4.110 a.u. for the six components of the 1 ³Π state in CsAg, whereas, at the scalar relativistic level of theory, the common value of Δμ is 2.494 a.u. [ABSTRACT FROM AUTHOR]