A general expression is obtained for the leading long-range correction to the static interaction of a slowly moving charged or neutral system at a large distance from a spherically symmetric atom, and precise estimates are presented of the magnitude for the systems H, $\mathrm{He} (1\mathrm{}{}_{}{}^1{}_{}{}^{}S,2\mathrm{}{}_{}{}^1{}_{}{}^{}S, \mathrm{and} 2{}_{}{}^3{}_{}{}^{}S)$, Ne, Ar, Kr, Xe, ${\mathrm{Li}}^{+} (1\mathrm{}{}_{}{}^1{}_{}{}^{}S,2\mathrm{}{}_{}{}^1{}_{}{}^{}S, \mathrm{and} 2{}_{}{}^3{}_{}{}^{}S)$, Li, Na, K, Rb, Cs, ${\mathrm{H}}_2$, ${\mathrm{N}}_2$, and C${\mathrm{H}}_4$.

• Received 17 July 1968

DOI:https://doi.org/10.1103/PhysRev.176.194