Analytical potentials for triatomic molecules from spectroscopic data

Analytic functions have been derived for the potential energy surfaces of the ground states of HCN (HNC) and HSiN(HNSi) using a combination of spectroscopic data and ab initio calculations. The potentials derived give no barrier to the approach of H to CN at any angle, but there is a barrier when H approaches SiN, this being larger at the Si end.