Energetic, geometric, and electronic evolutions of K-doped single-wall carbon nanotube ropes with K intercalation concentration
Energetic, geometric, and electronic evolutions of K-doped single-wall carbon nanotube ropes with K intercalation concentration
复制标题
DOI：
10.1103/physrevb.69.205304
复制
发表时间：
2004-05
影响因子：
3.7
通讯作者：
Jing Lu;S. Nagase;Shuang Zhang;Lianmao Peng
中科院分区：
文献类型：
--
作者：
Jing Lu;S. Nagase;Shuang Zhang;Lianmao Peng
采用第一性原理计算方法，系统研究了含K掺杂单壁（10，10）碳纳米管绳在K嵌入浓度下的能量、几何和电子演化.第一次从理论上证实了存在一个稳定的中间相（KexoC13.3）饱和（KexoC6.7）外的K掺杂（管外）之前。在具有开口端的单壁碳纳米管绳中的最佳K嵌入密度被预测为高达约KC 4.2，几乎是石墨中众所周知的值的两倍。简单的电荷转移模型只适用于低K掺杂水平的制度。近自由电子态与K4s轨道耦合，当管外和管内K掺杂浓度分别超过KexoC20和KendoC80时，较低的杂化态穿过费米能级.
The energetic, geometric, and electronic evolutions of a K-doped single-wall (10, 10) carbon nanotube rope with K intercalation concentration are systematically investigated by using first principles calculations. The existence of a stable intermediate phase (K exo C 13.3) before saturation (K exo C 6.7) for exohedral K doping (outside the tube) is first theoretically confirmed. The optimum K intercalation density in single-wall carbon nanotube ropes with open ends is predicted to be as high as about KC 4.2, nearly twice the well-known value in graphite. The simple charge transfer model is applicable only in the low-K doping level regime. The nearly free electron states of the nanotube couple with the K 4 s orbital, and the lower hybridized states do cross the Fermi level as the exohedral and endohedral (inside the tube) K doping densities exceed K exo C 20 and K endo C 80, respectively.