Vibrational relaxation and vibrational predissociation in DCl gas

The vibrational relaxation lifetime of compressed deuterium chloride is measured at room temperature as a function of density using time resolved laser induced fluorescence. The results, showing a deviation from the simple gas behavior, are interpreted as giving evidence of the role played by vibrational predissociation of dimers in vibrational relaxation, according to recent theories of vibrational predissociation. The lifetime measurement of low density deuterium chloride, obtained between −95 and +55 °C is first described and the results are quantitatively interpreted and compared to HCl gas.