Detailed quantummechanical calculations of molecular vibration frequencies of benzene, naphthalene, anthracene and phenanthrene. Comparison of several quantumchemical methods
Date
1994
Authors
Grampp, G.
Journal Title
Journal ISSN
Volume Title
Publisher
R Oldenbourg Verlag
Abstract
The reliability of the MNDO/PM3 semiempirical self-consistent field molecular orbital (SCF-MO) method for the calculation of fundamental vibration frequencies, and the effect of scaling are studied. The vibration frequencies of naphthalene were calculated by various semiempirical SCF-MO methods like MNDO/PM3, AMI, and MINDO/3. Results from the ab initio STO-3G model are also included for comparison. The MNDO/PM3 frequencies and geometries are in better agreement with experiment than the other methods. The errors in the MNDO/PM3 frequencies of benzene, naphthalene, anthracene and phenanthrene are mostly characteristic for specific types of vibration. The mean percentage deviation is 5.5% for all the modes of the molecules under investigation. A scaling procedure leads to frequency errors only within 2.8%. This agreement with experiment offers hope that MNDO/PM3 calculations may usefully contribute to the determination of harmonic frequencies. Calculations of that type may be of practical use in assignments of vibrational frequencies, especially for large molecules.
Description
Keywords
Chemistry, Vibration frequencies, Quantum chemistry, Aromatic hydrocarbons, Constants, Mndo, Ir-spectrum, Orbital methods, Methods, Semiempirical, Theoretical prediction, Condensed aromatics, Ground-states, Force-field, Dipole-moment derivatives
Citation
Cebe, E. ve Grampp, G. (1994). ''Detailed quantummechanical calculations of molecular vibration frequencies of benzene, naphthalene, anthracene and phenanthrene. comparison of several quantumchemical methods''. Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, 187(1), 15-32.