Predictive abilities of scaled quantum mechanical molecular force fields: application to 2,3-dimethylbuta-1,3-diene

• Published in: Structural chemistry Vol. 19; no. 5; pp. 793 - 799
• Main Authors: Panchenko, Yurii N., Bock, Charles W., Larkin, Joseph D., Abramenkov, Alexander V.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-10-2008
• Subjects: Chemistry; Chemistry and Materials Science; Computer Applications in Chemistry; Original Research; Physical Chemistry; Theoretical and Computational Chemistry; Vibrational analysis; Scaled quantum-mechanical force field; 2,3-Dimethylbuta-1,3-diene; MP2(FC)/aug-cc-pVDZ; Rotational isomers
• ISSN: 1040-0400; 1572-9001
• DOI: 10.1007/s11224-008-9366-z

In connection with the appearance of new experimental vibrational data on the high-energy rotational isomer of 2,3-dimethylbuta-1,3-diene (
I
) in a low-temperature matrix and in neat crystals, the ab initio-based vibrational analysis of this molecule has been re-evaluated. Calculated wavenumbers derived from a scaled quantum-mechanical force field analysis at the MP2(FC)/aug-cc-pVDZ//MP2(FC)/aug-cc-pVDZ computational level are compared with experimental data. Several reassignments of the fundamental wavenumbers for
I
have been suggested in the course of the current analysis, and the existence of a high-energy non-planar
s-gauche
conformer of 2,3-dimethylbuta-1,3-diene has been confirmed.