Finite-difference Dirac-Fock calculations of electric dipole polarisabilities for (ns)1and (ns)2atoms

Abstract
Finite-difference Dirac-Fock electric dipole polarisabilities alpha are reported for the (ns)1 ground states of Li, K, Rb and Cs and for the (ns)2 ground states of He, Be, Mg, Ca, Sr, Ba, Ra, Zn, Cd and Hg. The non-relativistic values increase from Ba to Ra and from Cd to Hg while the relativistic ones decrease. An alpha of about 240 au is predicted for Ra. Due to large correlation contributions, the present results are mainly of technical interest. The same numerical methods are used as in the previous Dirac-Fock one-centre expansion calculations. The principle of the program is explained here.