Nascent rotational and vibrational distributions in both products of the reaction Zn(4 1P1)+H2O→ZnH(X 2Σ+)+OH(X 2Π)

The reaction Zn(4 1P1)+H2O→ZnH(X 2Σ+)+OH(X 2Π) was studied under thermal equilibrium conditions at 700 K. The nascent internal state distributions of both products ZnH and OH were determined by using a pump-and-probe technique. The rotational distributions of ZnH and OH were both Boltzmann-like for their v″=0 vibrational levels. However, the rotational temperatures were significantly different—12 000 K for ZnH and 900 K for OH. ZnH was also vibrationally excited. The nascent vibrational distribution of ZnH was determined to be 10(v″=0):13(v″=1):7(v″=2):2(v″=3). In contrast, no excitation in the OH vibration was observed. Such a nonstatistical energy partitioning is explained by considering a short-lived Zn–H–OH intermediate in a nonlinear geometry.