Petkov V, Billinge SJ, Shastri SD, Himmel B. Polyhedral units and network connectivity in calcium aluminosilicate glasses from high-energy X-Ray diffraction.
PHYSICAL REVIEW LETTERS 2000;
85:3436-3439. [PMID:
11030915 DOI:
10.1103/physrevlett.85.3436]
[Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2000] [Indexed: 05/23/2023]
Abstract
Structure factors for Ca (x/2)Al xSi 1-xO (2) glasses (x = 0,0.25,0. 5,0.67) extended to a wave vector of magnitude Q = 40 A (-1) have been obtained by high-energy x-ray diffraction. For the first time, it is possible to resolve the contributions of Si-O, Al-O, and Ca-O coordination polyhedra to the experimental atomic pair distribution functions. It has been found that the connectivity of Si/Al-O tetrahedral network decreases with increasing x due to the emerging of nonbridging oxygens located on Si-O tetrahedra. Calcium maintains a rather uniform coordination sphere for all values of x and so it plays a certain role in determining the glass structure.
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