扶椅型碳纳米管能隙和电子结构密度泛函研究  

Density Functional Theory Study on the Energy Gap and Electronic Structure of Armchair Carbon Nanotube

作　　者：杨凯[1] 汪岳峰[1] 周全[1] 殷智勇[1] 强继平[1] 王军阵[1] 白慧君[1] 

机构地区：[1]军械工程学院电子与光学工程系,河北石家庄050003

出　　处：《材料科学与工程学报》2013年第5期748-751,702,共5页Journal of Materials Science and Engineering

摘　　要：本文建立了碳纳米管的结构模型,用平面波赝势方法,采用广义梯度近似的密度泛函理论,对扶椅型碳纳米管(5,5),(7,7)和(9,9)的能带结构和电子密度分布进行了计算,其能带间隙分别为0.024,0.142和0.147。计算结果表明碳纳米管(5,5)(7,7)(9,9)均为导体,在费米能级的电子密度均不为0,体现出金属性质。从电子结构上可以看出碳纳米管的电子分布在s亚层和p亚层上,由于碳纳米管弯曲,会形成不同形式的sp杂交轨道,但任何形式的碳纳米管在费米能级处的电子主要分布在p轨道。The structural models of （5,5）, （7,7） and （9,9） type carbon nanotubes were schematically constructed, and the energy gap as well as the electron distribution of these nanotubes were calcualted using the method of plan-wave pseudo-potential based on the scheme of generalized gradient approximation. The values of the energy gap of the three type carbon nanotubes are 0. 024eV, 0. 142eV and 0. 147eV, respectively. It indicates that carbon nanaotube （5,5） （7,7） and （9,9） are all conductors. Numbers of electrons are in Brillouin zone so that they behave like metals. It can be seen that the electrons are distributed in s and p orbits based on the electrical structure. Different type sp hybridization orbits are formed due to curved carbon nanotubes. The electron is distributed to p orbit near the Fermi energy.

关 键 词：扶椅型碳纳米管 密度泛函 能带间隙 电子结构 

分 类 号：O562[理学—原子与分子物理]