Synthesis, Optical Absorption, and Site-Selective Excitation of the ³P₀ Levels in Y₄Al₂O₉:Pr³⁺

Y4Al2O9:Pr3+ was prepared by two methods: starting from the citrates and direct sintering of the oxides. The latter method gave more single-phased samples. Optical spectroscopy was utilized to obtain the emission spectra from the individual sites of the crystal structure. Absorption, excitation spectra, and site-selective excitation into the 3P0 levels were utilized. Only three sites out of four were detected, and their energy levels were singled out. The crystal-field parameters of each set were determined, and an attempt was made to correlate optical spectra and crystallographic sites.