L. Cervinka et al., AN X-RAY STUDY OF PHOSPHATE-GLASSES OF THE COMPOSITION [M(PO3)(2)](N)(M=ZN, CU, MN, CA AND MG), Journal of non-crystalline solids, 193, 1995, pp. 121-124
An X-ray scattering study was undertaken of five phosphate glasses of
the general formula [M(II)(PO3)(2)](n), where M(II) = Zn, Cu, Mn, Ca a
nd Mg. Their melting temperatures and macroscopic densities as well as
X-ray scattering curves indicate an anomalous behaviour for the Mg ph
osphate glass. The first scattering peak (FSP) of the X-ray pattern is
located for all except the Mg phosphate glass at 1.7 Angstrom(-1) whi
le for the latter its position is 1.55 Angstrom(-1). Hence medium-rang
e density fluctuations of the order 5 Angstrom may be expected in the
Mg phosphate glass and of the order of 4.5 Angstrom for the remaining
glasses. The radial electron density distribution curves are all chara
cterized by the P-O coordination sphere at 1.55 Angstrom resulting fro
m the basic PO4/2 building block. The Me-O distances exhibit a linear
dependence on atomic number, with the exception of the Mg phosphate gl
ass (Mg-O = 1.9 Angstrom).