摘要
α-石英、β-石英、α-方石英、β-方石英和超石英是自然界中SiO_2常见的五种晶型.本文利用第一性原理平面波赝势方法,系统计算了五种SiO_2晶体的体弹性模量、电荷密度、电子态密度,能带结构,并和可获得的实验进行了比较.α-英、β-石英和具有空间群F d3m结构的β-方石英显示间接的带隙,而α-方石英,超石英和具有空间群P2_13和I42d结构的β-方石英显示直接的带隙.五种晶型SiO_2的带隙宽度均大于5.5 eV,都是绝缘体.
In nature there are five different types of SiO2 crystals (α-quart, β-quar, α-cristobalite, β-cristohalite and stishovite). In this paper the atomic and electronic structures of these SiO2 crystals are investigated from the plane wave pseudopotential method, and compared with the available experimental data. α-quart, β-quar and β-cristobalite with the space-group Fd3m symmetry exhibit the indirect band gap, whereas the band gaps of α-cristobalite, stishovite, β-cristobalite with P213 and I42d are direct. The band gap values of all types of SiO2 crystals are more than 5.5eV, indicating that they are all insulators.
出处
《原子与分子物理学报》
CAS
CSCD
北大核心
2010年第3期560-568,共9页
Journal of Atomic and Molecular Physics
基金
浙江省钱江人才计划项目(2007R10028)
国家自然科学基金(50802089)
高性能陶瓷和超微结构国家重点实验室开放课题基金(SKL200805SIC)
国家教育部和国家人事部留学回国人员基金([2008]890)
浙江省自然科学基金(Y4090280)
关键词
SIO2
电子结构
第一性原理计算
SiO2, electronic structure, first-principles calculations