  An accurate long-range {\em ab initio} potential energy surface has been
calculated for the ground state ${}^2A'$ lithium trimer in the frozen diatom
approximation using all electron RCCSD(T). The {\em ab initio} energies are
corrected for basis set superposition error and extrapolated to the complete
basis limit. Molecular van der Waals dispersion coefficients and three-body
dispersion damping terms for the atom-diatomic dissociation limit are presented
from a linear least squares fit and shown to be an essentially exact
representation of the {\em ab initio} surface at large range.
