杂质引起的双原子链晶格振动频率的变化

The Effect of Impurity on the Lattice Vibrational Spectum of a Diatomic Chain

对含单个杂质的双原子链的晶格振动模型的振动方程进行求解，得到了晶格振动频率和局域模频率的解析解，给出了该模型中杂质对双原子链的光学振动频率和声学振动频率的影响，并对局域模进行简要讨论。

The lattice vibrational equation of a diatomic chain with an impurity is solved. Theanalytic solutions of lattice vibrational frequency and local frequency are obtained. The effect of impurityon the optical and acoutic frequency of diatomic chain are given. The local mode is also discussed.