Molecular hydrogen isotopomers as traps of vibrational energy in low temperature matrices

The vibrational relaxation of 13C18O carbon monoxide in argon matrices doped with H2, D2 and HD has been studied. The effect of H2 addition is the strongest one when compared to other isotopomers of molecular hydrogen. The most probable mechanism of H2 interaction with vibrationally excited 13C18O is the V-R type of energy transfer, involving a ΔJ = 4 excitation of ortho-H2. For 13C18O/D2 and 13C18O/HD systems the evidence in favour of a V-V process, namely the exchange of two vibrational quanta of CO against one vibrational quantum of either D2 or HD, has been obtained.