The potential energy surfaces at different levels of ab initio electronic structure theory with correlation effects included are reported for rotation about the C(sp3)-C(aryl) bond in N-methylbenzamide. The results reveal a minimum at a C=C-C=O dihedral angle of ? 28? with barrier heights (MP2/aug-cc-pVTZ// BLYP/DZVP2/A2) of 0.48 kcal/mol at 0? and 2.80 kcal/mol at 90?. Fully optimized geometries are in good agreement with crystal structure data and potential energy surfaces are consistent with the experimental dihedral angle distribution. The results are used to assign MM3 force field parameters to allow calculation on N-methyl benzamide and other benzamide derivatives.
Revised: January 14, 2003 |
Published: February 1, 2001
Citation
Vargas-Fosada R.V., J. Garza-Olguin, D.A. Dixon, and B.P. Hay. 2001.C(sp(2))-C(aryl) Bond Rotation Barrier in N-Methylbenzamide.Journal of Physical Chemistry A 105, no. 4:774-778.PNNL-SA-33631.