Quantitative Analysis of Phosphorus and Aluminophosphate Complexes in Aluminophosphosilicate Glasses.

Raman spectroscopy has been used to quantitatively analyze phosphorus and aluminophosphate complexes in silica based glasses prepared by MCVD. A value of 8.15 x 10 sup (-delta) change in refractive index per mole percent Al0 sub 4 PO sub 4 complex has been determined. The refractive index of the compound glass may be represented accurately by a combination of the binary oxides Al sub 2 O sub 3 -SiO sub 2, P sub 2 O sub 5 -SiO sub 2 and AlPO sub 4 -SiO sub 2. The thermal expansion of these glasses does not fit a linear combination of the binary oxides, however, more work is planned in this area.