VIBRATIONAL-ENERGY TRANSFER AND QUENCHING OF OH A(2)SIGMA(+)(V'=1) MEASURED AT HIGH-TEMPERATURES IN A SHOCK-TUBE

Rate coefficients are reported for vibrational energy transfer and electronic quenching of OH A(2) Sigma(+)(v' = 1) by N-2, O-2, CO, CO2, NO, Ar, Kr, and Xe. Rate coefficients for electronic quenching of OH A(2) Sigma(+)(v' = 0) by the same set of collision partners are also reported. The measurements were performed at high temperatures (1900 and 2300 K) behind reproducible shock waves. The cross sections for quenching in v' = 1 were observed to be quite similar to the values found for quenching in v' = 0. For all of the species studied, the cross sections were found to be independent of temperature from 1900 to 2300 K. However, all of the high-temperature cross sections were found to be smaller than the previously reported values for quenching and vibrational energy transfer at 300 K. The decrease in the cross sections with temperature was observed to be more pronounced for vibrational energy transfer than for electronic quenching.