Higher order two- and three-body dispersion coefficients for alkali isoelectronic sequences by a variationally stable procedure

Using the variationally stable method of Gao and Starace, and the simple ground state wave function of the valence electron previously suggested by Patil and Tang, the multipolar polarizabilities of Li, Na, K, Rb, Cs, Be(+), Mg(+), Ca(+), Sr(+), Ba(+), the two-body dispersion coefficients of homonuclear and heteronuclear interactions from C(6) to C(40), as well as the three-body dispersion coefficients Z(L(1), L(2), L(3)) (up to L(i) = 5), are investigated. Higher order van der Waals dispersion coefficients C(n) (n > 24) and Z(L(1), L(2), L(3)) (L(i) > 3) are reported for the first time. Comparisons with previous calculations found in the literature show that this approach is capable of yielding precise and fast convergent values for higher order dispersion coefficients for alkali-metal atoms.