Long-range interactions between alkali Rydberg atom pairs correlated to the ns-ns, np-np and nd-nd asymptotes

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.