# ViPA: A computer program for vector projection analysis of normal vibrational modes of molecules

## Description

Abstract We describe a program designed to give a quantitative comparison of the normal vibrational modes of similar molecules by using calculated force constant matrices. The program uses the normal modes of one molecule to form a basis set to describe the normal modes of a second, similar molecule. Vibrational projection analysis, a specific application of vector projection analysis, is thus used to determine a percentage similarity by calculating the dot product between each of the 3N normal modes ... Title of program: ViPA Catalogue Id: ADID_v1_0 Nature of problem Provide a quantitative comparison of the normal vibrational modes [1] of similar molecules, including molecules related by a perturbation of atomic masses, chemical bonding, electronic states, non-covalent contacts or some other factor. This virtually automates the process of transferring normal mode descriptions from one molecule to another, structurally similar molecule. Versions of this program held in the CPC repository in Mendeley Data ADID_v1_0; ViPA; 10.1016/S0010-4655(98)00038-1 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)