Vibrational relaxation processes in a diatomic gas coupled to translational and radiational heat baths
Y. Ben-Aryeh, Aharon Postan
The relaxation of vibrationally excited diatomic molecules of one kind is studied by second-quantization methods. The relaxation processes are described by interactions of the vibrational degree of freedom with translational and radiational heat baths. General quantummechanical expressions are developed for transition rates in vibration-translation, vibration-vibration, and vibration-radiation processes. These expressions include the broadening of spectral lines in a nonequilibrium gas. The line broadening is affected by the correlation function of both the dipole moment and the density matrix. In the interaction of the vibrational degree of freedom with a radiational heat bath, cooperative effects are studied. Cooperative molecular effects do not influence the induced emission and absorption, but lead to changes in the process of spontaneous emission.
Physical Review A•May 1, 1974•7 citations