Electronic structure of silver halide doped glasses

A mechanism of enhancement of ionic conductivity by doping metal iodides into meta-silver phosphate glass has been investigated by ultra-violet spectroscopy and molecular orbital calculation. Absorption band around 4 eV was observed on AgI doped glasses. This band seems to be due to Ag–I molecule. At high concentration of AgI, the peak split and shifted. This spectral change coincides with the model of structural change of alternation and release of silver ion from non-bonding oxygen by the doped metal ion. Released silver ions seem to contribute to increased ionic conductivity.