CO product distribution from metastable levels of HCOXtilde;thinsp;2Arsquo;prepared by stimulated emission pumping

摘要

Vibrational and rotational distributions have been measured for the CO produced following dissociation of HCO prepared in metastable groundhyphen;state levels by stimulated emission pumping. The metastable levels are characterized by high vibrational excitation in the HCndash;O stretching coordinate. The CO (v=2) rotational distribution following dumping of population on theQR0(5) transition to the (0, 7, 0) level is rotationally cold and its distribution is in very good agreement with the theoretical prediction by Dixon. The linewidths for stimulated emission pumping transitions to the (0, 7, 0) and (0, 8, 0) levels are 1.0 and 1.6 cmminus;1, respectively. Since it is possible to prepare a wide variety of metastable HCO levels whose wave functions sample different regions of the HCO potential energy surface, measurement of the dissociation dynamics of HCO so prepared should provide a detailed picture of the potential surface at energies from 0ndash;10thinsp;000 cmminus;1above the dissociation limit.