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We present a simple illustrative one-electron scheme for the calculation of polarizability anisotropies of systems involving charge transfer processes. The method relies upon a frozen core assumption and the use of atomic Hartree–Fock wave functions to deduce the form of the one-electron potential by means of an inversion scheme. A basis set expansion technique is then applied to this potential. Polarizability anisotropies have been calculated for LiCl and KCl for internuclear separations up to 13 a.u. The agreement with Hartree–Fock finite-field calculations (which is generally good) reveals the dominance of charge transfer effects in these cases.

We present a simple one-electron central potential method which allows atomic photoionization cross sections to be calculated to an accuracy comparable to that of the best Hartree–Fock calculations available. The method relies upon the frozen core assumption and the fact that a good approximation to the Hartree–Fock potential seen by the photoelectron can be obtained by inversion of the corresponding ground state orbital as tabulated in the literature. The potential is assumed to be local and independent of final state energy in distinction to the true Hartree–Fock potential which is generally nonlocal due to exchange. Subshell photoionization cross sections for photon energies between 0 and 1500 eV have been calculated for helium, neon, argon, and krypton and compared with the Hartree–Fock results of Kennedy and Manson and available experimental values. The agreement is good except for near-threshold cross sections for deep lying orbitals. The method is compared with the Herman–Skillman approximation. The simplicity and computational efficiency of the present method suggest that it will be of use in practical calculations, particularly for heavy atoms. It offers a promising alternative to the widely used Hartree–Slater and Herman–Skillman calculations.