Triatomic potential surfaces. A catalogue of intersections

Abstract

Intersections of adiabatic electronic orbital potential energy surfaces for triatomic systems can be classified according to the point group in which the intersection occurs, and the following geometrical properties. The locus of the intersection in the three-dimensional configuration space of the system may be a surface, a curve or a point. When the locus is a curve, it may be of finite or infinite extent. In the neighbourhood of the intersection, the separation of the surfaces may be a linear, quadratic or higher order function of the displacement coordinates. In the asymptotic case, the surfaces intersect only when one atom is infinitely far from the other two. The various types of intersections are described and examples cited.