Abstract
The structures of
xCuO
·
(1
−
x)P
2O
5 glasses (0
⩽
x
⩽
0.50) prepared in vacuum sealed silica ampoules were investigated using vibrational spectroscopies. With the addition of CuO, both infrared and Raman spectra indicate a systematic transformation from a three-dimensional ultraphosphate network dominated by
Q
3 tetrahedra into a chain-like metaphosphate structure dominated by
Q
2 tetrahedra. IR spectra clearly show two distinct
Q
3 sites with bands at 1378 and 1306
cm
−1, assigned to P
O bonds on isolated
Q
3 tetrahedra and P
O bonds on
Q
Cu
3
tetrahedra that participate in the coordination environments of the Cu-octahedra, respectively. As CuO content increases, the intensity of the P
O band associated with the
Q
Cu
3
tetrahedra increases to a maximum
x
∼
0.33, then decreases with a concomitant increase of the intensity of the band at 1265
cm
−1, due to the asymmetric vibration of the PO
2 groups on
Q
2 tetrahedra. When
x
>
0.33 the isolated Cu-octahedra begin to share common oxygens to form a sub-network in the phosphate matrix. The effects of glass structure on the glass properties, including density, refractive index, and glass transition temperature, are discussed.