Application of empirical ionic models to SiO/sub 2/ liquid: potential model approximations and integration of SiO/sub 2/ polymorph data

Journal Article · Fri May 01 00:00:00 EDT 1987 · Geochim. Cosmochim. Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(87)90213-4· OSTI ID:6992527

Erikson, R L; Hostetler, C J

Structural and thermodynamic properties of crystalline SiO/sub 2/ and SiO/sub 2/ liquid have been examined with Monte Carlo (MC), molecular dynamics (MD), and energy minimization (EM) calculations using several ionic potential models obtained from the literature. The MC and MD methods calculate the same structural and thermodynamic properties for liquids when the same potential model is used. The EWALD (1921) method of calculating coulomb interactions reproduced most successfully the structure of liquid silica. The system internal energies show that liquid structures derived from random starting configurations can be metastable relative to structures calculated from crystalline starting configurations. The static lattice properties of the polymorphs alpha-quartz, coesite, and stishovite were used to evaluate further the accuracy of different sets of repulsive parameters for the full Ewald ionic model. Most of the models studied reproduced poorly the measured structures and elastic constants of the polymorphs. By using additional information to constrain the parameterization of the ionic model, such as estimated bond strengths and static properties of the silica polymorphs, a model more representative of the interparticle interactions may be obtained.

• Research Organization: Pacific Northwest Labs., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6992527
• Journal Information: Geochim. Cosmochim. Acta; (United States), Vol. 51:5
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
SILICA
GEOCHEMISTRY
MOLECULAR STRUCTURE
THERMODYNAMIC PROPERTIES
SILICATES
CRYSTAL LATTICES
CRYSTAL MODELS
MONTE CARLO METHOD
QUANTITATIVE CHEMICAL ANALYSIS
STRUCTURAL CHEMICAL ANALYSIS
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMISTRY
CRYSTAL STRUCTURE
MATHEMATICAL MODELS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SILICON COMPOUNDS
SILICON OXIDES
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