LOCAL-STRUCTURE OF ER3+ IN MULTICOMPONENT GLASSES

Erbium environments in several multicomponent glasses are investigated using X-ray absorption fine structure spectroscopy on the Er L-III-ed ge. Glass hosts studied include aluminosilicate, fluorosilicate, phosp hosilicate, alkali phosphate, fluoride, and another multicomponent sil icate glass. The Er-O separation is found to vary only slightly betwee n 2.21 and 2.25 Angstrom. The first shell coordination number is depen dent on glass host ranging from 6.3 nearest neighbor anions in the alu minosilicate glass to 10.0 in the fluoride host. The Debye-Waller fact or for the first shell is also host dependent. It ranges from 0.021 An gstrom(2) in the phosphate hosts to 0.033 Angstrom(2) in the aluminosi licate glass. While Er-Er correlations are observed in the crystalline Er2O3 standard, no evidence of molecular or short-range clustering of Er3+ ions is found in the glasses. Photoluminescence spectra are also presented for each of the glass hosts examined. (C) 1938 Elsevier Sci ence B,V. All rights reserved.