Knowledge Bank

Infrared spectra of the connected rotational levels of jet-cooled CH$3$OD are recorded in the OD stretch region. The observed spectra in the range 2710 - 2740 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$ result from E-species transitions ($30\leftarrow 3-1$,$20\leftarrow 31$,$10\leftarrow 11$) of CH$3$OD. For the available rotational levels (K $\prime$ = 0 , K $\prime$ = 1 and K $\prime$ = 2), the reduced torsional energies follow a pattern similar to the ground state. The torsional tunneling splitting in the OD stretch excited state is deduced to be 2.4 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$ as compared to 2.6 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$ in the ground state.