HYPERVIRIAL THEOREMS FOR MULTIPOLE MOMENT OPERATORS

Off-diagonal hypervirial theorems are constructed to allow an alternative method of evaluation of transition multipole matrix elements, and are applied to the Hartree-Fock-Slater self-consistent field calculations of electric quadrupole transition matrix elements of atomic lithium, which may become measurable through the quadrupole birefringence experiment. The results are compared with those obtained using numerical Hartree-Fock self-consistent functions and the Coulomb approximation.