State-to-state and total rotational energy transfer rate constants for CN(B 2Σ+,v=0,N)+H2, CN(X 2Σ+,v=2,N)+H2, D2, and CN(X 2Σ+,v=3,N)+NO

Abstract

State-to-state and total rotational energy transfer (RET) rate constants were measured for collisions of CN(B 2Σ+,v=0,Ni=4,7,8,11) with H2, CN(X 2Σ+,v=2,Ni=4,11) with H2 and D2, and CN(X 2Σ+,v=3,Ni=4) with NO at room temperature and under single, or near-single, collision conditions. Rate constants were also measured for electronic quenching of CN(B 2Σ+,v=0,Ni=4,7,8,and 11) by H2. In general, state-to-state RET rate constants showed very small or no even–odd alternations as the final rotational state varied. Total rate constants for CN(X 2Σ+,v=2,N)/H2, D2 were found to decrease with increasing rotational quantum number, N. By contrast, total rate constants for CN(B 2Σ+,v=0,N)/H2 were found to be relatively independent of N. Exponential energy gap and angular momentum fitting functions were found to represent measured state-to-state RET rate constants very well and were substantially equally effective in this regard.