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Theoretical and Experimental Chemistry

, Volume 22, Issue 5, pp 509–520 | Cite as

Investigation of the electronic structure and properties of cluster models of silica by the MNDQ method

  • Yu. I. Gorlov
  • V. A. Zaets
  • A. A. Chuiko
Article

Abstract

Using the LCAO MO SCF method in the MNDO valence approximation, we have carried out a systematic study of the electronic and spatial structure of cluster models of the bulk phase and the hydroxylated and chemically modified surface of silica surface. We propose a technique for taking into account the crystallochemical environment of the clusters modeling the bulk phase of SiO2, based on passivation of the abnormal valencies at the boundary of the clusters by hydrogen atoms, the geometrical location of which ensures homogeneity in the electron density distribution on the silicon atoms of the model fragment. We give a comparative analysis of the electronic characteristics of the studied cluster models. We consider the nature of the adsorption centers and the properties of the hydroxylated and modified silica surface.

Keywords

SiO2 Hydrogen Atom Silicon Atom Cluster Model Silica Surface 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Publishing Corporation 1987

Authors and Affiliations

  • Yu. I. Gorlov
    • 1
    • 2
  • V. A. Zaets
    • 1
    • 2
  • A. A. Chuiko
    • 1
    • 2
  1. 1.Division of Surface Chemistry, L. V. Pisarzhevskii Institute of Physical ChemistryAcademy of Sciences of the Ukrainian SSRUSSR
  2. 2.Institute of Colloidal Chemistry and Chemistry of WaterAcademy of Sciences of the Ukrainian SSRKiev

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