Modified Semiempirical Approach to the H3 Potential-Energy Surface

Abstract

A modification of the Porter—Karplus potential‐energy surface for H₃ is formulated in which maximum use is made of diatomic potential‐energy functions for both H₂ and H₂⁺. In this formulation, the classical barrier height is found to vary by several kilocalories when scaling functions are altered slightly or when three‐center integrals are ignored. Results are compared with several other semiempirical surfaces and with presently available a priori calculations.