本研究是以量子分子動力學模擬奈米碳管之電弧製程在不同製成參數上之探討。參數有管徑之大小、基板溫度、沉積原子的入射動能。
首先，原子間的勢能函數採用Tight-Binding 多體勢能來計算，
並遵循牛頓第二運動定律，在整個數值計算方面採用Leap-Frog 修正
法來計算系統原子受力後的位置和速度等物理量，並使用Verlet 鄰
近表列和截斷勢能法的演算法則來計算原子間的相互作用力，以減少
整個電腦數值模擬的運算時間。
由模擬結果發現：
1. 剛開始成長時，當管徑越小，越容易形成五角環，而管徑越大，越容易形成六角環。

2. 不管任何管徑，溫度越大，越容易形成封閉端，這是因為溫度越大，則管的端部原子震動頻率會加快，會增加管末端封閉的機會。
3. 管徑較小的碳管：當入射的原子動能越大，則促使端部的原子會有較大的位移，因此封閉時間會縮短，但當入射動能過大，會影響到封閉端原子的鍵結，會因此在端部無法形成封閉端，而會形成紊亂的結構。相對管徑較大的碳管：大管徑上形成的封閉結構，其封閉端的穩定性較小管徑的差，因此，雖然入射動能較大，會讓封閉更快速，但是能影響封閉端原子的鍵結之入射動能，就會相對比小管徑的還小。

In this study, the arc vaporization which makes nanotubes have been simulated by quantum molecular dynamics for different manufacture parameters. Parameters are radius of nanotube, substrate temperature and incident energy of droping atoms.
First, The many body potential functions for intermolecular are described by the tight-binding potential. Following the second law of Newton, the Leap-Frog method is adopted to calculate atom’s physical properties, such as position and velocity, etc. To reduce the computer simulation time, the algorithms of Verlet list and cut-off potential are applied to calculate the interactive force between atoms.
The results of loading :
1. When the radius of tube is getting small, it is easier to form the pentagon from the beginning of growth. And when the radius of tube is getting bigger, it is easier to form the hexagon.
2. No matter how the radius of tube is, when the temperature is getting hotter, it is easier to form the closed-end. This is because when the temperature gets hotter, the vibration frequencies of atoms in the end of the tube would get more quickly. And it would also increase the opportunities to seal the end of the tube.
3. The smaller radius tube of carbon nanotube: When the incident kinetic energy of atoms get larger, it would make a bigger displacement of atoms in the end of the tube; therefore it would shorten the closed-time. But while the incident kinetic energy is much larger, it would affect the binding of the closed-end of atoms and would form the disorder structures. In opposition, atoms in the end of the tube which the bigger radius tube is much stable than the small ones. So incident energy of bigger radius tube which can disturb the cap structure is less than small ones.

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