Hydroxyl groups in phosphosilicate glass for optical fibers

To gain insight into the local environment of impurity hydroxyl groups in phosphosilicate glass and determine its signatures in the vibration spectrum, the IR absorption spectra of phosphosilicate glasses containing up to 20 mol % P2O5 were analyzed. The interaction of hydroxyl groups with phosphorus-containing centers was studied with the use of a cluster model and the PM3 and MNDO quantum-chemical methods. The observed changes in the OH-stretching region of the absorption spectrum were interpreted using the modeling results.