# Rotation-vibration eigenvalues and vectors

## Description

Abstract We describe a method for obtaining the bound ro-vibrational states of polyatomic molecules through the expansion of the potential in terms of appropriate functions of internal coordinates. Using this method, the calculation of potential matrix elements in greatly simplified and the algorithm is ideally suited to the vector machine like Cray. Programs for potential matrix calculation and matrix diagonalization are given with the results of a test run. Title of program: SLEIGC Catalogue Id: ABDT_v1_0 Nature of problem This routine finds the lowest eigenvalues and their associated eigenvectors of very large matrices. Versions of this program held in the CPC repository in Mendeley Data ABDT_v1_0; SLEIGC; 10.1016/0010-4655(88)90071-9 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)