Nonadiabatic eigenfunctions can have conical nodes

摘要

It has been argued the total vibrational probability amplitude for a molecular nonadiabatic eigenfunction should not have nodes unless required by symmetry. For a model with two nonadiabatically coupled electronic states, exact factorization of nonadiabatic eigenfunctions into a total vibrational probability amplitude and a normalized electronic factor reveals zero-dimensional nodes in nonadiabatic eigenfunctions over a two-dimensional vibrational space. These conical nodes have the shape of a right elliptical cone with the node at the vertex. Low dimensionality nodes are likely when the number of nonadiabatically coupled electronic states is less than or equal to the dimensionality of the vibrational space. (C) 2017 Elsevier B. V. All rights reserved.