Global fit of ab initio potential energy surfaces: II. 1. Tetraatomic systems ABCD

Global potential energy surfaces (GPES) for general tetraatomic molecular s ystems which fit ab initio data can be obtained preserving the accuracy of the ab initio points. The global fitting technique is based in a procedure for tetraatomic systems including the functional form previously proposed b y the authors. The global fit obtained fulfills the stringent criteria need ed for molecular dynamical calculations. The program writes out as output f ile a Fortran-77 program in a form such that the potential and its derivati ves with respect to coordinates can be evaluated readily and accurately at arbitrary geometries. (C) 2001 Elsevier Science B.V. All rights reserved.