纳米一维单原子晶体颗粒的原子均方位移

摘要

The formula of mean-square displacements of atoms in onedimensional monatomic nanoparticles is deduced by means of the theory of Greens function. The numerical results are obtained in the high-temperature limit, the results show that the mean-square displacements of all atoms are directly proportional to temperature, the mean-square displacements of inner atoms are smaller than those of surface atoms. The mean-square displacements of surface atoms and centeral atoms increase, and the mean value of mean-square displacements of all atoms also increases when the size of nanoparticle increases.%应用格林函数理论，推导了纳米一维单原子晶体颗粒的原子均方位移公式.数值计算结果表明，在高温近似下，所有原子的均方位移与温度成正比，纳米晶体颗粒内部原子的均方位移小于表面原子的均方位移.随纳米晶体颗粒的尺寸增加，表面和中央原子的均方位移都增加，而纳米晶体颗粒中的所有原子的均方位移的平均值也增加.