金刚石单空位的分子动力学模拟

用分子动力学方法模拟了金刚石中单空位的最近邻原子和次近邻原子的弛豫过程，计算所用的碳原子间相互作用势为Tersoff多体经验势.结果表明，单空位的最近邻原子是向外弛豫的，平均弛豫幅度约为2×10

Molecular Dynamics Simulation of the Single Vacancy in Diamond

The relaxation process of the nearest and second nearest neighbor atoms around a vacancy in diamond was simulated by molecular dynamics. The atomic interaction was described by Tersoff's many-body empirical potential. The results show that the nearest neighbor atoms of the vacancy is 2×10-2 nm outward, which is in good agreement with the results obtained by ab-inito and cluster theory. The second nearest neighbor atoms move inward at the moment that the vacancy is introduced. Later, they vibrate outward or inward, and the average magnitude of relaxation is outward by 7×10-4 nm. In addition, the relaxation orientation of the nearest neighbor atoms has changed and deviates from 〈111〉 direction by 0.14° after the introduction of the vacancy. The average bond length between the nearest and second nearest neighbor atoms of the vacancy is 0.15 nm and shortened by 4×10-3 nm.