First-Principles Study of Several Novel Silica Framework Structures
نویسندگان
چکیده
(ABSTRACT) Several novel silica structures have been generated using a simulated-annealing strategy with an ab-initio based covalent-bonding potential. First-principles total-energy pseu-dopotential methods have been used to examine several promising novel structures and to compare their structural parameters, cohesive energies and bulk moduli with those of low-quartz, low-cristobalite, silica-sodalite and stishovite. The cohesive energies of these novel structure types are found to be equivalent to those of low-quartz, low-cristobalite, silica-sodalite and significantly lower than that of stishovite.
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