INTERACTION POTENTIALS FOR HE-F- AND NE-F-

Ab initio potential energy curves for the interaction of a fluoride an ion with a He atom and a Ne atom-are obtained by supermolecular CCSD(T ) calculations, that is, coupled cluster calculations in the space of: single and double substitutions corrected noniteratively for triple su bstitutions. The computations include full counterpoise corrections an d employ large basis sets with bond functions. The CCSD(T) potential e nergy curves have significantly deeper wells than their many-body pert urbation theory counterparts. Fits to functional forms that reproduce the CCSD(T) points with an average absolute error less than 0.3% are r eported. (C) 1998 American Institute of Physics. [S0021-9606(98)30132- 4].