Spectral-luminescent characteristics of Sr2Y8(SiO4)602: Eu powder crystal phosphor with the apatite structure and high-intensity luminescence of Eu3+ ions have been studied. The charge state of europium in the samples has been characterized by means of X-ray L-3-adsorption spectroscopy. It was established that Eu3+ forms two types of optical centers. Besides, luminescence of Eu(2+)ions was found. Reduction Eu3+ -> Eu2+ was considered, which may be due to V-Sr(parallel to) vacancy formation in the 4f crystal lattice position and to negative charge transfer by this vacancy to two Eu-gamma(3+) ions. Thus, in the silicate lattice there exist inhomogeneously distributed oxygen-deficient centers, which are responsible for nonradiative transfer of excitation energy to Eu3+ and Eu2+ ions. To study electron-vibrational interactions in the crystal phosphor samples, their IR and Raman spectra were examined. In the luminescence spectrum of Eu2+, a series of low-intensity bands caused by interaction of the 4f(6)5d state of Eu2+ with silicate lattice vibrations was observed. (C) 2010 Elsevier Inc. All rights reserved.