OPTICAL AND X-RAY ABSORPTION-MEASUREMENTS ON SUPERIONIC (AGI)X(AG2ONB2O3)1-X GLASSES

The glasses (AgI)//x(Ag//2O n B//2O//3)//1// minus //x have been studied by optical and X-ray absorption spectroscopy at various x and n concentrations. The optical absorption of the n equals 4 glasses shifts linearly at the increasing of the AgI content x. Extrapolating to x equals 1, the corresponding value for alpha -AgI is crossed. The comparison of the EXAFS (extended X-ray absorption fine structure) structures at the I L//3 edge of the n equals 3, x equals 0. 3 glass and of beta -AgI seems to indicate that the Ag-I coordination is substantially unmodified in the glass with respect to that in beta -AgI.