An accurate in-plane force field for porphine. A scaled quantum mechanical study

by Kozlowski, Pawel M.; Zgierski, Marek Z.; Pulay, Peter

The ground state geometry, force field, and vibrational intensity data of free-base porphine were determined by density functional theory. Calculations were carried out with the Becke-Lee-Yang-Parr composite exchange-correlation functional and 6-31G* basis set. The calculations predict a stable structure of D-2h symmetry. The resulting force field was transformed to internal coordinates and scaled by transferable scale factors from our previous work. There is very good agreement between the calculated and experimental frequencies and intensities, and between experimental and simulated spectra. The assignment of the in-plane modes is discussed and some reassignments are proposed. Finite field perturbation theory was used to obtain the Raman intensities.

Journal
Chemical Physics Letters
Volume
247
Issue
4-6
Year
1995
Start Page
379
ISBN/ISSN
1873-4448; 0009-2614
DOI
10.1016/S0009-2614(95)01247-8