Structure and properties of low-silica calcium aluminosilicate glasses

The structure of three calcium aluminosilicate glasses with low-silica content (61CaO.39Al(2)O(3) (Ca0.39), 55CaO.35Al(2)O(3).10SiO(2) (Ca10.35) and 49CaO.31Al(2)O(3).20SiO(2) (Ca20.31)), synthesized by a standard quenching technique, were studied by X-ray and neutron diffraction. The data are consistent with the hypothesis that Si and Al are present in tetrahedral sites and Ca in octahedral sites for all compositions. Si-T (T = Si or Al) and Si-O-2 contributions (where O2 means the second nearest oxygen) appear at 10 mol% silica content, which indicate that silicon enters the aluminate network. (C) 2000 Elsevier Science B.V. All rights reserved.