Self-Consistent Perturbation Method. I. Calculation of Dipole Polarizability and Shielding Factor

A variation method has been described which yields self-consistent wave function for an atom or molecule subjected to a perturbing field of the type Σ i h 1 ( i ). Through minimization of the second-order energy, completely coupled perturbed orbitals are obtained in the Hartree-Fock scheme. A calculation of the dipole polarizability and shielding factor has been done for atoms and ions of He, Li and Be isoelectronic sequences. The present results are of much higher accuracy than those hitherto obtained by other methods.