| Abstrakt: |
State-to-state vibrational energy transfer and electronic quenching in the lower vibrational levels, v′≤3, of the B 3∏(0u+) state of 79Br2 were investigated using spectrally resolved, temporally resolved laser induced fluorescence techniques. Emission from v′ = 1 to 3 after laser excitation of low rotational levels, J≊10, in v′ = 2–3 was observed for the following collision partners: He, Ne, Ar, Kr, Xe, N2, NO, O2,SF6, and Br2. The vibrational energy transfer is quite rapid in these levels and is adequately described by the Montroll–Shuler model for harmonic oscillators. The probability for V–T transfer from v′ = 1 to v′ = 0 ranged from P=0.048±0.006 for He collisions to 0.20±0.02 for Br2 collisions. The effect of predissociation on the evolution of the vibrational population distributions is analyzed. The present results are compared to similar studies of vibrational transfer in the B 3∏(0u+) states of IF, BrF, and BrCl by examining the scaling of V–T transfer probabilities with reduced mass of the collision pair and vibrational energy spacing. The range of the interaction potential is derived for the rare gas collision partners from the Schwartz, Slawsky, Herzfeld theory as 0.15 Å for Xe to 0.5 Å for He. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR] |
