Journal of Sol-Gel Science and Technology

, Volume 8, Issue 1–3, pp 55–58 | Cite as

Atomistic modeling of silica based sol-gel processes

  • J. C. G. Pereira
  • C. R. A. Catlow
  • G. D. Price
  • R. M. Almeida
Article

Abstract

Density Functional Theory is used to study water, methanol, ethanol, TMOS, and TEOS molecules and the most important silica clusters participating in sol-gel processes. Calculated bond lengths, bond angles and electric dipole moments compare well with experimental data. The energy of these molecules is reported and used to discuss the energetics of the hydrolysis and condensation reactions. Molecular Dynamics is employed to simulate liquid water, methanol, ethanol, TMOS, TEOS and experimental sol-gel solutions. Calculated densities and enthalpies of vaporisation compare well with experimental data. Preliminary results are presented for MD simulations of sol-gel solutions.

Keywords

Molecular Dynamics Density Functional Theory sol-gel solutions silica clusters 

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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • J. C. G. Pereira
    • 1
  • C. R. A. Catlow
    • 1
  • G. D. Price
    • 2
  • R. M. Almeida
    • 3
  1. 1.The Royal Institution of Great BritainLondonUK
  2. 2.Dept. Geol. SciencesUniversity College LondonLondonUK
  3. 3.Dept. Eng. MateriaisInstituto Superior TécnicoLisboaPortugal

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