Theoretical Models of Silica Nanorings: First-Principles Calculations

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• 作者：Zexiao Xi ; Mingwen Zhao ; Ruiqin Zhang ; Shishen Yan ; Tao He ; Weifeng Li ; Xuejuan Zhang ; Xiaohang Lin ; Zhenhai Wang ; Xiangdong Liu ; Yueyuan Xia
• 刊名：Journal of Physical Chemistry C
• 出版年：2008
• 出版时间：November 6, 2008
• 年：2008
• 卷：112
• 期：44
• 页码：17071-17075
• 全文大小：222K
• 年卷期：v.112,no.44(November 6, 2008)
• ISSN：1932-7455

文摘

We performed first-principles calculations on silica nanorings (NRs) designed via the assembly of two- (2MR), three- (3MR), four- (4MR), and six-membered rings (6MR) in a number of different ways. The stable configurations, energetics, and electronic structures of these NRs are presented. The most stable configurations were found to be size-dependent and to possess different structural features at different size ranges. For small-size silica NRs (SiO₂)_n with n < 12, the configurations with 2MR−3MR hybrid structures (2−3MR-NRs) were energetically most stable. For 12 < n < 22, the NRs formed from linked 2MRs (2MR-NRs) became most favorable. For n > 22, the configurations composed of uniformly hybrid 2MRs and 4MRs (2−4MR-NRs) were the most stable structures. The 2−4MR-NRs had the narrowest HOMO−LUMO gaps, which decreased with decreasing n.