The room-temperature photoluminescence spectrum of SiO2 glass : 0.1% Cr prepared by sol-gel method is reported. It consists of a broad band centered at 14 900 cm(-1) with a width of 4200 cm(-1) and a lifetime in the mu S Order and is attributed to the d-d transition of Cr5+ ions (3d(1) electron configuration). Absorption and emission spectra give no evidence for the presence of Cr3+ Or Cr4+ ions.