Effective-Field Calculations of Polarizabilities and Shielding Factors for He, Ne, A, and Kr Isoelectronic Series

Abstract

Electronic dipole and quadrupole polarizabilities and the Sternheimer shielding or antishielding factors are calculated for several closed-shell atomic systems. The calculations are carried out by an effective-field method using the perturbed orbitals, given by the uncoupled Hartree-Pock method, as trial functions. The external field is replaced either by a mean effective field taking into account the mean coupling between the deformations of the various orbitals or by a set of effective fields, each of them being relative to a particular perturbed orbital. Numerical results obtained for the He, Ne, A, and Kr isoelectronic series show a much better agreement with the corresponding coupled values than the initial uncoupled results.

Differential scaling of σ and π orbitals, and the geometric approximation for molecular polarizabilities

“…Results of a similar nature were obtained by Litt in connection with atomic calculations [4]. The multiple scaling had significance in relation to the detailed contributions but it had no importance in the overall results.…”

Static Dipole Polarizability of Atoms and Ions in the Thomas-Fermi Model

“…1. The dashed curve Za corresponds to the multiplythat formula (18) is valid if (2 -N ) / Z > 0.5 or 2 > 2N. Thus, knowing the nuclear charge Z and the number of electrons N and using the universal curves given on Figs.…”

Molecular mechanics study of ion binding by a cyclic pentapeptide

“…Except for the three amide protons, which were explicitly included, all hydrogen atoms were treated implicitly by regarding methyl and methylene groups as extended atoms (19). The polarizability of Li' , needed to compute the lithium nonbonded interaction parameters, was assigned the experinientally determined value of 0.025 A3 (21); 0.60A was used as the Li' van der Waals radius, and the effective number of Li'valence electrons was set to 2.…”