title: Location of Two Seams in the Proximity of the C2v ππ* Minimum Energy Path of Formaldehyde.
abstract: Photochemical reactions rationalization is a key aspect for the understanding and setup of novel experiment and novel photoinitiated pathways. In this respect, the relationship between minimum energy paths over an excited-state and the intersection to lower potential energy surfaces is fundamental. In order to help the understanding of this relationship, in this study we present a novel kind of constraint for geometry optimizations, namely, an "orthogonality" constraint. Its possible applications are described. A complete example on how to retrieve the direct relationship between a minimum energy path over an excited-state potential energy surface and a conical intersection seam is given for C2v symmetry constrained formaldehyde. The advantages of using the novel constraint when rationalizing a (photo)chemical reaction are presented.
authors.affiliation: Department of Theoretical Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden.
authors.forename: Luca
authors.initials: L
authors.lastname: De Vico
authors.affiliation: Department of Theoretical Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden.
authors.forename: Roland
authors.initials: R
authors.lastname: Lindh