Knowledge Bank

Infrared studies have been made of pure and mixed HCl and DCl crystals in the overtone region. In addition to the transitions resulting from the double excitation of one molecule, and the single excitation of two identical molecules, a relatively strong transition results from the simultaneous single excitation of one HCl molecule and one DCl molecule in the mixed crystals. The frequency shifts of the dilute isotopes from their gas phase values, and the effects of concentration, will be discussed.