Ultrafine Cr-doped Al2O3 prepared by detonation synthesis

Data are presented on the phase composition, particle size distribution, EPR, and luminescence of ultrafine chromium-doped alumina powders prepared by detonation synthesis. The largest particles in the powders are shown to consist mainly of a Cr2O3 solid solution in α-Al2O3. The luminescence spectrum of fine particles shows, in addition to lines characteristic of ruby, extra lines which are tentatively attributed to Cr3+ ions incorporated substitutionally into θ-Al2O3.