H3 potential surface in natural collision coordinates

Abstract

Potential energy contour maps of the ground and electronically excited Porter-Karplus H3 surfaces are presented. These maps are correlated with another set of figures showing molecular geometries. Particular attention is paid to the intersection of these electronic surfaces along the Jahn-Teller ridge. A difficulty with natural coordinates, “nonlinear schizophrenia”, is described and a simple procedure for avoiding the problem is presented.