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把分析型嵌入原子法(AEAM)和晶格动力学理论相结合,在三维布喇菲晶格振动模型的基础上模拟了面心立方金属Au、Ag、Pt、Cu和Ni沿[00ζ]、[0ζζ]、[ζζζ]和[0ζ1]4个对称方向的声子色散曲线.结果表明:模拟曲线与实验点线符合的较好,特别在低频附近二者几乎一致,而在纵波模(L)q=(001)2π/a,q=(111)2π/a和横波模(T2)q=(011)2π/a三个布里渊区边界点附近,两者在数值上略有差异;沿[00ζ]和[ζζζ]两个高对称性方向上,横模T1和T2简并为一个横模T;在同一对称方向上,五种面心立方金属Au、Ag、Pt、Cu和Ni的频率随原子质量的增大而依次减小.
Based on the three-dimensional Brafit lattice vibration model, the surface-centered cubic metal Au, Ag, Pt, Cu and Ni along the [00ζ], [0ζζ], [ζζζ] and [0ζ1] were obtained.The results show that the simulated curve is in good agreement with the experimental point line, especially near the low frequency, while in the longitudinal mode (L There is a slight difference in numerical value between the two Brillouin boundary points at q = (001) 2π / a, q = (111) 2π / a and the transverse mode (T2) q = In the direction of [00ζ] and [ζζζ], the transverse modes T1 and T2 are degenerated into a transverse mode T. In the same symmetry direction, the five face-centered cubic Au, Ag, Pt, Cu and The frequency of Ni decreases with the increase of atomic mass.