采用密度泛函理论中的广义梯度近似对(SiO2)n-(n≤7)负离子团簇的几何构型进行了优化,并对能量和频率进行了计算.通过对计算结果的分析发现,与近邻尺寸的团簇比较,(SiO2)4-团簇最低能量结构更加稳定;(SiO2)n-(n≥4)团簇的最低能量结构是以(SiO2)4-为基础结构,具有一定的生长规律.
Geometric structures of(SiO2)n-(n≤7)anion clusters are optimized by using the generalized gradient approximation density functional theory.The energy and vibrational frequency have been calculated.The lowest energy(SiO2)4-cluster is found to be more thermodynamically favored compared with other neighboring sized cluster isomers.Additionally,the lowest energy(SiO2)n-(n≥4)clusters grow up regularly based on the lowest energy(SiO2) 4-cluster.