EXAFS study of alkali galliosilicate glasses

The extended X-ray absorption fine structure (EXAFS) of Na 2OGa 3SiO 2 glasses of 3 compositional series containing either a constant Na 2O or SiO 2 content, or a constant Ga/Na ratio of 1.0, analogous crystalline compounds and 4 potassium-containing glasses were measured on the SUNY X21 beamline of the National Synchrotron Light Source at Brookhaven National Laboratory. The data were analyzed to extract Ga K-edge position, coordination numbers and GaO bond lengths for each glass composition. This study indicates that the GaO bond length is 1.83 Å, and that the coordination number of oxygen about gallium is constant at 4, regardless of glass composition.