VIBRONIC ABSORPTION-SPECTRA OF P4+ AND P3 IN SOLID ARGON

White phosphorus vapor (P4) was passed through a short argon discharge and subjected to vacuum ultraviolet radiation during condensation with excess argon. Visible absorption spectra revealed two vibronic band systems. A photosensitive progression with 436-nm origin and 550 ± 10-cm-1 vibrational interval maps the photoelectron spectrum of P4+, which confirms this assignment. A broader band with a 427-nm origin and 480 ± 20-cm-1 interval increased on visible photolysis and decreased on sample annealing; this absorption is assigned to the P3 radical. © 1990 American Chemical Society.