THE DIODE-LASER SPECTRUM OF 3 ISOTOPIC FORMS OF PBH IN ITS 2-PI-1/2 GROUND-STATE

The infrared spectrum of three isotopic forms of the lead hydride radical in natural abundance (208PbH: 52.3%, 207PbH: 22.6%, 207PbH: 23.6%) in its ground electronic state (2Π 1 2) has been observed using a diode laser spectrometer. These measurements have provided the first information about the magnitude of the Λ-type doubling in PbH which is considerably larger than that observed in other 2Π diatomic hydrides. The wavenumber of 35 transitions of the fundamental band and the first hot band of each isotopic species have been measured with a nominal accuracy of ±0.001 cm-1. Analysis of these data has produced the first values for the Λ-doubling parameters and the most accurate set of ground-state parameters for PbH. © 1990.