C. Johann et al., ASYMPTOTIC THEORY FOR THE (2)SIGMA(U) VAN-DER-WAALS POTENTIALS OF ALKALI DIMER CATIONS, Chemical physics letters, 295(1-2), 1998, pp. 158-166
The (2)Sigma(u) state Van der Waals potentials of alkali dimer cations
Li-2(+), Na-2(+), K-2(+), Rb-2(+) and Cs-2(+) are calculated from the
asymptotic exchange and polarization energies. The potentials of all
these systems are generated by the same analytical formula with parame
ters depending only on the properties of the atomic constituents. The
results agree with accurate CI calculations. The dipole-dipole-quadrup
ole hyperpolarizability for these systems is large and it is necessary
to include this third-order term in the polarization energy for an ac
curate determination of the potential. However, the overlap correction
and the damping of the induction series, although conceptually import
ant, have only a minor effect. (C) 1998 Elsevier Science B.V. All righ
ts reserved.