ROTATIONALLY INELASTIC-COLLISIONS OF LIH WITH HE .1. ABINITIO POTENTIAL-ENERGY SURFACE

The diagrammatic many-body perturbation theory is applied through third order in the correlation energy to the interaction potential between He and a rigid LiH molecule. The ab initio calculations are used to derive an analytic representation of the potential surface in terms of orthogonal polynomials. Several different basis sets are employed to demonstrate the sensitivity of the energies to the computational techniques. The resulting potential surfaces are highly anisotropic with respect to the LiH center-of-mass and allow for a weak binding (∼7 meV) of the He to the Li end of the LiH axis. © 1980 American Institute of Physics.