Long-range interactions between alkali Rydberg atom pairs correlated to the<i>n</i>s–<i>n</i>s,<i>n</i>p–<i>n</i>p and<i>n</i>d–<i>n</i>d asymptotes

Abstract

We have calculated the long-range interaction potential curves of highly excited Rydberg atom pairs for the combinations Li–Li, Na–Na, K–K, Rb–Rb and Cs–Cs in a perturbative approach. The dispersion C-coefficients are determined for all symmetries of molecular states that correlate to the ns–ns, np–np and nd–nd asymptotes. Fitted parameters are given for the scaling of the C-coefficients as a function of the principal quantum number n for all homonuclear pairs of alkali metal atoms.