The change of picture contribution to relativistic corrections to second-order properties

Citation
P. Turski et Aj. Sadlej, The change of picture contribution to relativistic corrections to second-order properties, CHEM P LETT, 338(4-6), 2001, pp. 345-352
Citations number
30
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
CHEMICAL PHYSICS LETTERS
ISSN journal
00092614 → ACNP
Volume
338
Issue
4-6
Year of publication
2001
Pages
345 - 352
Database
ISI
SICI code
0009-2614(20010427)338:4-6<345:TCOPCT>2.0.ZU;2-O
Abstract
The effect of the so-called change of picture for operators in approximate relativistic theories on the second-order properties arising from some exte rnal perturbation, is considered. By means of the direct perturbation theor y the general formula for the lowest-order relativistic correction to secon d-order properties is derived. The term which arises from the change of pic ture for the external perturbation operator is identified and evaluated for dipole and quadrupole polarizabilities. For the 1s(1/2) state of the hydro gen-like ions this term is found to bring about 16% and 7% of the total low est-order irelativistic correction to the dipole and quadrupole polarizabil ities, respectively. This finding is discussed in terms of its importance f or long range interactions between heavy systems. (C) 2001 Elsevier Science B.V. Ail rights reserved.