Infrared-Emission Studies of Electronic-to-Vibrational Energy Transfer. III. Hg* + NO

Electronic-to-vibrational transfer has been observed in the system Hg*(63P1,0)+NO. Both Hg*(63P1) and Hg*(63P0) have been found to be effective in bringing this about. A set of rate constants, kv (or cross sections σv2) for electronic-to-vibrational transfer were derived according to various models from an observed set of steady-state concentrations, Nv. The set of kv bear a qualitative resemblance to those for Hg*+CO (Part II). Hg*+NO exhibits a significant but slowly diminishing probability for vibrational excitation into vibrational levels up to v=16 or 17, and an insignificant probability for vibrational excitation into higher levels than v=16–17, corresponding to ⅔ of the electronic energy converted into vibration. The qualitative similarity of these results to those obtained for Hg*+CO suggests that a similar mechanism may be applicable here: Hg*+NO→HgNO*→HgNO→Hg+NO†. However, there exists in the present system an alternative mechanism which would involve electronic-to-electronic transfer: Hg*+NO(X 2Π)→Hg+NO*(4Π), followed by formation of NO† in the ground X 2Π state by collisional deactivation of NO*(4Π). The total cross section for electronic-to-vibrational transfer with Hg*(63P1) as the donor was estimated to be (σvib2)1=1–15 Å2, and that with Hg*0 as donor (σvib2)0=0.05–1.0 Å2.