Ab initio vibrational analysis of 3,3-dimethyl-1-butene

The geometry of 3,3-dimethyl-1-butene was completely optimized by ab initio calculations at the HF/6-31G** and HF/6-31G** levels. The quantum-mechanic al force fields were calculated for the optimized geometries. Scale factors were determined to correct the HF/6-31G**//HF/6-31G** and HF/6-31G**//HF/6 -31G* quantum-mechanical force fields. The assignments of some experimental vibrational bands of 3,3-dimethyl-1-butene were revised.