Journal of Chemical Physics, Vol.101, No.7, 5700-5707, 1994
V-E Energy-Transfer in Ethylene and Alkali Gas-Mixtures Using Infrared Multiphoton Excitation
V-E energy transfer in C2H4 and alkali gas system C2H4double dagger+M-->C2H4+M*(M=Na, K, Rb, and Cs, double dagger denotes high vibrationally excited state, * denotes electronically excited state) was investigated by using IR multiphoton excitation of C2H4 and probing the atomic fluorescence due to the above process. The atomic decay rates were determined as a function of alkali or ethylene gas concentration. The rate constants of V-E energy transfer were originally obtained by comparing the decay rate under different experimental conditions with the solution of the set of equations based on a proposed kinetic model. The kinetic information with respect to the inverse E-V energy transfer and the deexcitation process of the highly vibrationally excited state C2H4double dagger were also obtained which agreed well with the results obtained from other methods. The large cross sections of the V-E energy transfer and their weak dependence on temperature obtained were interpreted based on a harpooning mechanism.
Keywords:VIBRATIONAL-ENERGY;POLYATOMIC-MOLECULES;FOREIGN GASES;RELAXATION;COLLISIONS;STATE;PHOTODISSOCIATION;FLUORESCENCE;DEPENDENCE;CO