Charge transfer spectra of metal ions in glass

Many metal ions impair ultraviolet transparency when present in glass owing to charge transfer absorption bands. Existing relevant spectroscopic data, although limited, do indicate that the principle of optical electronegativity can be applied and that the onset of ultraviolet impairment is linked to the state of polarisation of the oxygen atoms. Linking optical electronegativity with optical basicity allows a rough estimation of frequency shift for changes in glass composition.