Knowledge Bank

The infrared spectra of $CH2SeH,CH2SeD,CD3SeH$ and $CD3SeD$ have been investigated from $250cm-1$ to $4000cm-1$ in both the vapor and the solid states. The Raman spectra of all four compounds in the liquid phase have been recorded. A complete vibrational assignment and normal coordinate calculation have been carried out. In $CD3SeH$ a large repulsion exists between the methyl wagging mode and the Se-H bending vibration. The far infrared spectrum of $CH3SeH$ has a broad band centered at about $145\pm 40cm-1$ which is assigned to the torsional vibration. A height of $320\pm 40cm-1$ for the barrier to internal rotation is calculated from the torsional frequency. Present address of Albert B. Harvey: U. S. Naval Research Laboratory, Washington, D.C.