Knowledge Bank

The theory of torsion-vibration-rotation interaction in ethane is presented and applied to the high resolution infra-red spectra of the bands $\nu 11 + \nu 4$, $\nu 12 + \nu 4$, and $\nu 8$. The barriers to internal rotation in the states $\nu 11$ and $\nu 12$ are found and compared to that of the ground state.