Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-25T17:47:24.862Z Has data issue: false hasContentIssue false

Clustering and Extended Range Order in Binary Network Glasses

Published online by Cambridge University Press:  10 February 2011

Dmitry Nekhayev
Affiliation:
Department of Materials Science & Engineering, University of Illinois, Urbana IL 61801
John Kieffer
Affiliation:
Department of Materials Science & Engineering, University of Illinois, Urbana IL 61801
Get access

Abstract

The clustering in alkali silica glasses (M2O) x (SiO2)1-x, where M is either Na or Rb, and x ranges between 0 and 0.4, was studied using molecular dynamics simulations. Computations were performed using a semi-empirical potential, including two- and three-body terms as well as dynamic partial charge transfer. Characterization of the structures was based on pair correlation functions, neutron static structure factor and ring statistics. Results have shown a much stronger tendency to cluster in case of Na than of Rb. The irregular arrangement of Na is evidenced by a decay pattern in the Na-Na pair correlation function, which can be associated with a fractal dimension. The clustering tendency can be attributed to the differences in the way the network structure is able to accommodate the introduction of modifying cations. As opposed to Rb, the smaller Na cation can fit on sites only slightly larger than is required for Si. This would distort the structure but hardly alter its topology. Rb on the other hand, requires larger interstices, which results in a reconstruction of the network and a significantly different intermediate range order. Na can achieve a similar influence on the network structure if they group in pairs.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Zarzycki, J., Rivista della Staz. Sper. Vetro, 5(1990) 13.Google Scholar
2. Shramm, C.M., Long, B.H.W.S. De Parziale, V.E.J., J. Amer. Chem. Soc., 106(1984) 4396.Google Scholar
3. Farnan, I., J.F.Stebbins, J. Amer. Chem. Soc., 112(1990) 32.Google Scholar
4. Henderson, G.S., J. Non-Cryst. Solids, 183(1995) 43-50.Google Scholar
5. Hannon, A.C., Vessal, B., Parker, J.M., J. Non-Cryst. Solids, 150(1992) 97.Google Scholar
6. Warren, B.E., Biscoe, J., J. Am. Cer. Soc., 21(1938) 259.Google Scholar
7. Vessal, B., Greaves, G., Marten, P.T., Chadwick, A.V., R.Mole, S.Houde-Walter, Letters to Nature, 356(1992) 504.Google Scholar
8. Kieffer, J., C.A.Angell, J. Chem.Phys., 90(1989) 4982.Google Scholar
9. Anderson, D.C., Kieffer, J., Klarsfeld, S., J. Chem. Phys. 98(1993) 8978.Google Scholar
10. Dove, M.T., Introduction to Lattice Dynamics, Cambridge Univ. Press 1993 154159. Google Scholar
11. Sinclair, R.N., Wright, A.C., J. Non-Cryst. Solids 57(1983) 109.Google Scholar
12. Iyetomi, H., Vashishta, P., Phys. Rev. B, 47(1993) 3063.Google Scholar
13. Rino, J.P., Ebbsjo, I., Kalia, R.K., Nakano, A., Vashishta, P., Phys. Rev. B, 47(1993) 47.Google Scholar
14. Franzblau, D.S., Phys. Rev. B, 44(1991) 4925.Google Scholar