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496. POLYMODE: Vibrational Energies for Coupled
Anharmonic Oscillators
by Hubert Romanowski and Joel M. Bowman, Department of Chemistry, Illinois Institute of Technology, Chicago, Illinois 60616 POLYMODE is a program to calculate vibrational eigenenergies and eigenvectors by variational CI method for up to 10 coupled anharmonic oscillators. The calculations in either normal coordinates with the full Watson Hamiltonian (J=O), i.e., with vibration-rotation (Coriolis) interaction for nonrotating molecules, or in internal coordinates with constant G-matrix, may be performed in uncoupled anharmonic oscillators bases and/orinvibrationalself-consistent-field (VSCF)/virtual bases. The primitive bases (modals) are represented by linear combinations of harmonic oscillator eigenfunctions (LCHO). The potential energy is accepted in both types of coordinates in the form of Taylor expansion up to quartic order. FORTRAN 77 (VAX) Lines of Code: 2527 |