MOLECULAR VIBRATIONS BY A MATRIX FORCE METHOD.

Abstract

The utility was ascertained of an existing very large IBM 7094 digital program, based on a matrix force method, to the area of molecular vibrations. The derivation of the matrix force method is outlined and compared with the matrix displacement method. Some structural elements, useful in consideration of molecular vibrations, are illustrated. The frequencies and normal vibrational modes of the molecule ethylene were computed. The excellence of the agreement between the computed and observed frequencies and between the normal modes calculated by the program and by conventional techniques demonstrates the extreme versatility of the computer program. A valence force field approximation was used. The computer program is of such generality that virtually any force field approximation may be employed (including the widely used Urey-Bradley force field and modifications of it). The capability of the program to handle extremely large problems opens new vistas in the theoretical study of vibrations of conventional molecules and of such large and complex systems as molecular and ionic crystals, molecules of biological interest and polymers.

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1964
Accession Number
AD0625874

Entities

People

  • David B. Hall
  • Joyce J. Kaufman
  • Stanley Kaufman

Tags

DTIC Thesaurus Topics

  • Agreements
  • Alkenes
  • Complex Systems
  • Computer Programs
  • Computers
  • Crystals
  • Displacement
  • Ethylenes
  • Frequency
  • Frequency Shift
  • Ionic Crystals
  • Molecules
  • Vibration

Readers

  • Polymer Science and Technology
  • Structural Dynamics.
  • Systems Analysis and Design