Vibrational frequencies and structural determination of dimethylketene

The vibrational frequencies and corresponding normal mode assignments of dimethylketene are examined theoretically using the Gaussian98 set of quantum chemistry codes. All normal modes were successfully assigned to one of nine types of motion predicted by a group theoretical analysis (C-H stretch, C-C stretch, CCO symmetric stretch, CCO asymmetric stretch, CCO bend, C-C-C bend, H-C-H bend, CH3 twist, and CH3 wag) utilizing the C2v symmetry of the molecule.