Author Name | Affiliation | E-mail | Ji-nan Lü | Department of Modern Mechanics, University of Science and Technology of China, CAS Key Laboratory
Mechanical Behavior and Design of Materials, Hefei 230027, China | | Hai-bo Chen* | Department of Modern Mechanics, University of Science and Technology of China, CAS Key Laboratory
Mechanical Behavior and Design of Materials, Hefei 230027, China | hbchen@ustc.edu.cn | Pin Lü | Department of Modern Mechanics, University of Science and Technology of China, CAS Key Laboratory
Mechanical Behavior and Design of Materials, Hefei 230027, China | | Pei-qiang Zhang | Department of Modern Mechanics, University of Science and Technology of China, CAS Key Laboratory
Mechanical Behavior and Design of Materials, Hefei 230027, China | |
|
Abstract: |
The modied molecular structural mechanics method (MMSMM) is extended to analyze the dynamic characteristics of single-walled carbon nanotubes (SWCNTs). In MMSMM, the deformation potential of SWCNT is decomposed and it can be easily expressed as the function of the positions of carbon atoms in molecular mechanics, and so the sti?ness matrix of SWCNT can be obtained. The elemental mass matrix is a diagonal one, so the natural frequency and vibration mode of SWCNT can be calculated e?ectively. In this work, the form of cantilevered nanotubes is analyzed. The natural frequencies of SWCNT computed by this algorithm are discussed. The frequency dependence on the tube diameter and length of SWCNT is conˉrmed and, it is shown that when the diameter of tube is small the frequency can reach the the GHz level. The frequency results and the vibration modes are comparable with those of other researchers. Furthermore, a new FEM continuum-model is proposed to analyze the dynamic character of SWCNT to compare with these results by MMSMM. |
Key words: Carbon nanotube, Molecular mechanics, Modiˉed molecular structural mechanics method, Natural frequency |
FundProject:the National Basic Research Program of China (No.2006CB300404) |
|
单壁碳纳米管的振动频率 |
吕计男,陈海波*,吕品,张培强
|
摘要: |
将修正的分子结构力学方法(MMSMM)扩展用来分析单壁碳纳米管的动态特性. 应用MMSMM方法分析了悬臂单壁碳纳米管的振动特性,对计算得到的单壁碳纳米管振动的基频进行了讨论. 发现单壁碳纳米管振动的基频与碳管的直径和长度有关,呈现出一定的尺度依赖性,当管径很小的时候,单壁碳纳米管的振动基频可以达到GHz.并尝试用有限元方法模拟碳管的振动问题. 两种方法得到的结果表明,在常用的原子模拟方法(如分子动力学方法)解决碳纳米管振动问题遇到困难时,通过扩展修正可以简单的处理这类问题,并可以保持很好的精度. |
关键词: 碳纳米管,分子力学,修正的分子结构力学,基频 |
DOI:10.1088/1674-0068/20/05/525-530 |
分类号: |