Variational calculation of dynamic polarizabilities

✍ Scribed by M. Krauss; D. Neumann

• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 256 KB
• Volume: 52
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(77)80518-6

✦ Synopsis

The finite field method of obtaining static multipole polarizabilitics is extended to the calculation of dynamic polarizabilitics. The first-order frequency dependent wavcfunction is obtained variationally using a trial function, h(w) Q,(O). I,!J~(O) is the first-order wavcfunction obtained in the static calculation.

The results are applied to the approximation of the dynamic polarizability at Imaginary frequencies. These are then used to calculate the coefficients for the inverse power series reprcscntatton of the interatomic potential energy. The method has been applied to two simple cases, hydrogen and helium. For hydrogen the present method yields results close to the exact values for the static dipoie polarizability and the dipole-dipole van dcr Waals cocfficicnt, c6. In the case of helium a simple Hartree-Fock function was perturbed but the results arc still encouraging with the dipole-dipole van der Waals coefficient, c6, calculated to within 7% of the accurate