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1 Lead metal was vaporized and trapped in solid xenon at 12K. Electronic absorption and resonance Raman spectra were recorded of the resulting matrix, which was shown to contain Pb ? , Pbl , and possibly Pb 4 molecular species. The vibrational frequency for Pb 2 is determined to be 108 cm-1 for the ground state, with a dissociation energy of -18200 cm-1 . A 03h symmetry is indicated for the Pb3 species, with v l=117 cm-1 and v2= 96 cm-1. The existence of Pb 4 is suggested by a fundamental and overtone of 111 cm-1 spacing.