生长中纳米碳管的电子结构

利用第一原理的离散变分方法计算了生长中纳米碳管团簇的电子结构,发现悬挂键的存在导致管口处的电子结构明显地不同于管体,对应的非键合价电子不仅直接改变管口处碳原子之间的键合模式,而且进一步增强管口处碳原子之间的结合,促使碳原子只向管芯移动,这与实验中观察到的封闭顶端的几何形态相一致;而且降低碳管的化学稳定性.与完整型纳米碳管截然不同的电子结构决定了生长中纳米碳管在合成纳米材料过程中具有不同的作用行为.

Electronic Structure of Carbon Nanotube in the Growth

The electronic structure of single walled carbon nanotube (SWNT) in the growth is studied by using the first principle discrete variable calculations. We find the electronic structure of the mouth is remarkably different from that of the body due to dangling bonds. The corresponding valence electrons not only directly change the bonding model of the mouth, strengthen the bonding between carbon atoms and induce carbon atoms shift to tube core along the radial, which is in good agreement with the morphology of perfect tip observed in the experiments, but also reduce the chemical stability of carbon nanotube. The electronic structure differing from the closed carbon nanotube determines the different operation behavior of carbon nanotube in the growth in the synthesis of nano material.