基于曲率和电子结构的掺杂C50和C70富勒烯的稳定性研究

使用密度泛函理论(DFT)-B3LYP/6-31G^*方法研究了B、N、Si、P和Co在C₅₀和C₇₀中的掺杂能和电子结构, 并基于曲率理论和电子结构探讨了掺杂富勒烯的结构稳定性. 计算结果表明, 掺杂能随着原子曲率的增大而减小, 随着掺杂物种原子半径的增大而增大, B、N、P和Co的掺杂有利于C₅₀结构的稳定, 而B和N的掺杂不利于C₇₀结构的稳定; 除了用于反映原子活性的曲率主要决定掺杂反应性, 各不等价碳原子在C₅₀和C₇₀的最高占据分子轨道(HOMO)中所占成分对掺杂能的影响也很大, 且其成分越大越有利于掺杂. 此外, 掺杂原子得失电子情况与其电负性有关. 本工作将为富勒烯结构稳定性的研究提供理论依据.

Stability of Doped C50 and C70 Based on Curvature and Electronic Structures

The doping energies and electronic structures of B, N, Si, P, and Co in C₅₀ and C₇₀ were investigated using the density functional theory (DFT)-B3LYP/6-31G^* method, and the structural stabilities of doped fullerenes were investigated based on curvature theory and the electronic structures. The calculated results showed that the doping energies decreased with increasing curvature, and increased with increasing atomic radius of the doping species. Doping with B, N, P, and Co stabilized the C₅₀ structure. However, doping with B and N was disadvantageous for the structural stability of C₇₀. The doping reactivities were mainly determined by the curvature and related to the percentage of nonequivalent carbon atoms in the highest occupied molecular orbital (HOMO), and a large percentage was beneficial for the doping stability. In addition, whether the doped atoms accepted or lost electrons depended on their electronegativity. This work will be helpful for the stabilization of fullerene structures in experiment.