Oligomerization in silica sols

• Published in: Journal of physical chemistry (1952) Vol. 94; no. 13; pp. 5351 - 5356
• Main Authors: Feuston, B. P, Garofalini, S. H
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01-06-1990
• Subjects: 400201 - Chemical & Physicochemical Properties; CALCULATION METHODS; CHALCOGENIDES; CHEMICAL REACTIONS; Chemistry; Colloidal gels. Colloidal sols; Colloidal state and disperse state; COLLOIDS; DISPERSIONS; ELEMENTS; Exact sciences and technology; General and physical chemistry; HYDROGEN; HYDROGEN COMPOUNDS; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; INTERATOMIC FORCES; MATHEMATICAL MODELS; MINERALS; NONMETALS; OXIDE MINERALS; OXIDES; OXYGEN; OXYGEN COMPOUNDS; POLYMERIZATION; SILICA; SILICON COMPOUNDS; SILICON OXIDES; SOLS; WATER; Water; Intermolecular interaction; Binary mixture; Oligomerization; Simulation; Silicic acid; Molecular dynamics; Theoretical study; Colloidal sol
• ISSN: 0022-3654; 1541-5740
• DOI: 10.1021/j100376a035

An empirical potential containing two- and three-body terms for silica-water interactions is proposed, with the oxygen-oxygen interaction treated identically in both the water and vitreous silica subsystems. The structures of water, H{sub 2}O dimers, H{sub 2}O trimers, and the H{sub 4}SiO{sub 4}-H{sub 2}O complex obtained by molecular dynamics simulations are in reasonable agreement with X-ray diffraction of water and ab initio calculations of molecules. Simulations of monomeric silicic acid sols provide a microscopic description of water producing oligomerization. The intermediate activation complexes are found to involve ionized monomers and pentacoordinate silicon.