The electronic structure of agr;hyphen;quartz: A periodic Hartreendash;Fock calculation

摘要

The electronic structure of agr;hyphen;quartz has been calculated using the periodic Hartreendash;Fock method. Charge density maps, band structure, and density of states have been computed and are discussed. An overall agreement with available experimental results and with previous calculations performed within different theoretical approaches is found. In particular it is shown that lsquo;lsquo;cluster typersquo;rsquo; calculations on molecules such as H6Si2O7accurately reproduce the charge density in the neighborhood of the bridging oxygen. Geometry optimizations yield realistic values of the SiO bond length and of the SiOSi angle.