This project in the Theoretical and Computational Chemistry Program concerns the development and application of methods for approximate computation of coupled vibrational motions of nuclei in molecules. Applications will include studies of van der Waals molecule dissociation, intramolecular vibrational relaxation, isomerization reactions, and vibrational eigenvalue studies. Particular emphasis will be placed on development of mean-field techniques expressed in optimized general coordinates. Such a treatment will allow for consideration of more complex chemical systems than are currently accessible by exact quantum techniques.