Electronic quenching of NH(C1π)

The fluorescence lifetime of NH(c,v,J) has been investigated for v = 0, J = 2-9 and v = 1, J = 1, 4. Rate constants for quenching of NH(c, v = O) in thermal equilibrium at 298 K have been measured for 15 collision partners and for NH(c, v = O) in nonequilibrium for 8 partners. Most rate constants are near gas kinetic and decrease as the energy of the colliding pair increases. Comparison with NH(A) shows in many cases roughly a factor of 2 difference in the cross sections while there is near quantitative agreement with the cross sections for OH(A). Comparisons with the cross sections for the quenching of O({sup 1}D) show a linear relationship with nonpolar and polar collision partners falling on separate parallel lines. Both the well-depth model and the complex-formation model show reasonable correlations with the data.