石墨等电子体B_4C_3二维平面材料的结构与成键分析
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- 英文论文题名：Structure and Bonding of A B_4C_3 Nanosheet Isovalent With Graphene
- 论文作者：田欣欣 ; 穆跃文 ; 吕海港 ; 李思殿
- 英文论文作者：Xinxin Tian ; Yuewen Mu ; Hai-Gang Lu ; Si-Dian Li ; Nanocluster Laboratory ; Institute of Molecular Science ; Shanxi University
- 年：2016
- 作者机构：山西大学分子科学研究所;
- 论文关键词：B4C3 ; 二维材料 ; 全局搜索 ; 第一性原理计算
- 会议召开时间：2016-07-01
- 会议录名称：中国化学会第30届学术年会摘要集-第十八分会：电子结构理论方法的发展与应用
- 语种：中文
- 分类号：O613.81;O641.1
- 学会代码：ZGHY
- 会议名称：中国化学会第30届学术年会-第十八分会 ; 电子结构理论方法的发展与应用
- 会议地点：中国辽宁大连
- 主办单位：中国化学会
- 学会名称：中国化学会
- 页数：1
- 文件大小：349k
- 原文格式：D
- 会议级别：全国
摘要
石墨烯发现以后,纯B二维材料与B-C二维材料引起了人们的广泛关注。Tang等人~([1])理论预测了自由B二维材料的稳定结构(α-sheet)。该结构与石墨烯为等价电子体系,具有独特的六元环与填充六元环排布。B_4C_3二维材料是与石墨烯等价电子的B-C二元体系。本文采用Calypso软件~([2])和第一性原理计算对B_4C_3二维平面结构进行了全局搜索,发现其稳定结构具有六元环孔洞与填充六元环交替排布的特性,其中每个填充六元环被六个等价六元环孔洞包围,每个六元环孔洞周边均匀分布着三个填充六元环(Fig.1)。能带分析表明,不同于石墨烯、硼α-sheet及其它比例二维B-C材料的金属特性~([2]),B_4C_3二维材料为间接带隙半导体。SSAd NDP成键分析揭示了该二元结构独特的化学成键:每个B_4C_3结构单元形成6个3c-2eσ键和1个7c-2eπ键,并对其周边的6个2c-2eσ键及6个6c-2eπ键各贡献一半价电子(Fig.1)。换言之,每个填充六元环和六元环孔洞各覆盖一个离域π键,填充六元环之间通过定域σ键相连,而填充B原子同时参与3c-2e离域σ键和7c-2e离域π键。
Two-dimensional B_4C_3 nanostructure was predicted based on unbiased Calypso global research and theoretical calculations.It is found that the most stable structure has alternant distribution of empty and filled hexagons and results in an indirect bandgap semi-conducting behavior, which is different from other stoichiometric ratio 2D B-C nanostructures.Chemical bonding analysis by SSAd NDP indicate that, there are six 2c-2e σ bonds, six 3c-2e σ bonds, six 6c-2e π bonds and one 7c-2e π bond in each B_4C_3 unit cell(Fig.1).In other words, 6c or 7c-π bond found over every hexagon, the center B atom formed 3c-σ bond with each edge of hexagon, and all hexagons are bonded through 2c-σ bond.Such a bonding pattern is very similar to that of graphene.
Two-dimensional B_4C_3 nanostructure was predicted based on unbiased Calypso global research and theoretical calculations.It is found that the most stable structure has alternant distribution of empty and filled hexagons and results in an indirect bandgap semi-conducting behavior, which is different from other stoichiometric ratio 2D B-C nanostructures.Chemical bonding analysis by SSAd NDP indicate that, there are six 2c-2e σ bonds, six 3c-2e σ bonds, six 6c-2e π bonds and one 7c-2e π bond in each B_4C_3 unit cell(Fig.1).In other words, 6c or 7c-π bond found over every hexagon, the center B atom formed 3c-σ bond with each edge of hexagon, and all hexagons are bonded through 2c-σ bond.Such a bonding pattern is very similar to that of graphene.
引文
[1]Tang,H.;Ismail-Beigi,S.Phys.Rev.Lett.2007,99:115501.
[2]Luo,X.;Yang,J.;Liu,H.;Wu,X.;Wang,Y.;Ma,Y.;Wei,S.-H.;Gong,X.;Xiang,H.J.Am.Chem.Soc.2011,133:16285
[2]Luo,X.;Yang,J.;Liu,H.;Wu,X.;Wang,Y.;Ma,Y.;Wei,S.-H.;Gong,X.;Xiang,H.J.Am.Chem.Soc.2011,133:16285