Polarizabilities and Dispersion Coefficients

Zong-Chao Yan

The static dipole, quadrupole and octupole polarizabilities for the ground state of positronium hydride (PsH) are calculated using variational wavefunctions in Hylleraas coordinates. The two- and three-body dispersion coefficients for the interactions among PsH, H, He and Li are determined.

Xi Chu, A. Dalgarno, Gerrit C. Groenenboom

The dynamic scalar and tensor polarizabilities of Sc and Ti are computed with time-dependent density functional theory. These polarizabilities are used to compute the isotropic and anisotropic dispersion interactions in ScHe and TiHe. We find ${C}_{6,0}(\mathrm{ScHe})=30.00$, ${C}_{6,2}(\mathrm{ScHe})=\ensuremath{-}1.63$, ${C}_{6,0}(\mathrm{TiHe})=28.40$, and ${C}_{6,2}(\mathrm{TiHe})=\ensuremath{-}0.90$ $({E}_{h}{a}_{0}^{6})$. We show that an estimate of the dispersion anisotropy based on static polarizabilities results in an overestimation by a factor of 2.

J. Mitroy, M. W. J. Bromley

The van der Waals coefficients, ${C}_{6},{C}_{8},$ and ${C}_{10}$ for the alkali-metal (Li, Na, K, and Rb) and alkaline-earth-metal (Be, Mg, Ca, and Sr) atoms are estimated by a combination of ab initio and semiempirical methods. Polarizabilities and atom-wall coefficients are given as a diagnostic check, and the lowest order nonadiabatic dispersion coefficient, ${D}_{8}$ and the three-body coefficient, ${C}_{9}$ are also presented. The dispersion coefficients are in agreement with the available relativistic many-body perturbation theory calculations. The contribution from the core was included by using constrained sum rules involving the core polarizability and Hartree-Fock expectation values to estimate the f-value distribution.

Valerii S. Butylkin, Yury G. Khronopulo, A. E. Kaplan +1 more