[5,5] 和 [9,0] 单壁碳纳米管的电子结构和能量特性
Jerzy Cioslowski1, Niny Rao, David Moncrieff
1Department of Chemistry and Biochemistry and School of Computational Science & Information Technology, Florida State University, Tallahassee, Florida 32306, USA. jerzy@kyoko.chem.fsu.edu
Journal of the American Chemical Society
|July 11, 2002
概括
这项研究计算了有限长度单壁碳纳米管 (SWNT) 的性能. SWNT属性取决于长度,帽子的方向,并表现出与尺寸的缓慢融合.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 单壁碳纳米管 (SWNT) 具有独特的电子和结构性质.
- 了解这些特性对于设计先进的纳米材料至关重要.
研究的目的:
- 计算有限长度扶手椅和曲式SWNT的关键热力学和电子特性.
- 为了研究管道长度和帽子方向对SWNT特征的影响.
主要方法:
- 使用B3LYP/6-311G*理论水平进行密度函数理论 (DFT) 计算.
- 计算形成的标准度,电离潜力,电子亲和和带间隙.
主要成果:
- SWNT属性对管子长度和帽子方向 (对于齐格扎格的SWNT) 非常敏感.
- 有限长度扶手椅SWNT显示尺寸依赖的振荡行为,反映金属特征.
- 预测Zigzag SWNTs是半导体,无论上限如何.
结论:
- 随着管子长度的增加,SWNT的特性慢慢地趋同.
- 沿着SWNT轴线观察到小的辐射扭曲.
- 这项研究为SWNT属性的大小和结构依赖提供了宝贵的见解.
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