金属铬的声子色散关系及振动特性  

Study on phonon dispersion relation and vibration characteristic of metal chromium

作　　者：张晓军[1,2] 王安祥[1] 陈长乐[2] 

机构地区：[1]西安工程大学理学院,陕西西安710048 [2]西北工业大学陕西省凝聚态结构与性质重点实验室,陕西西安710072

出　　处：《纺织高校基础科学学报》2015年第1期79-84,共6页Basic Sciences Journal of Textile Universities

基　　金：陕西省教育厅科研专项基金资助项目(14JK1301);陕西省自然科学基金资助项目(2012JM1011)

摘　　要：利用改进分析型嵌入原子法模型和晶格动力学理论,在谐和近似下重现体心立方金属铬沿[ζ00]、[ζζ0]和[ζζζ]3个高对称方向上声子色散关系的实验结果,预测沿[α1-αα]、[α1-α0]和[0.5 0.5α]3个低对称方向上的声子色散关系,并讨论不同对称方向上不同色散线的兼并特征和振动性质.结果发现:高对称方向上声子色散曲线的计算结果与实验结果整体一致,特别在低频附近二者相一致,在高频附近,计算结果与实验结果所对应的色散曲线形状相似,数值上稍有偏差.在[ζ00]和[ζζζ]2个高对称方向上,振动方向不同的两支声频横波线AT1和AT2兼并为一支声频横波线AT;在[ζζ0]高对称方向和低对称方向上都没有兼并现象.Using the modified analytic embedded atom method and the theory of lattice dynamics,the experimental results of the phonon dispersion relation in bcc metal chromium along three high symmetry directions[ζ00],[ζζ0]and[ζζζ]are reproduced and the phonon dispersion relations of strontium along three low symmetry directions [α1-αα],[α1-α0]and[0.5 0.5α]are predicted within the harmonic approximation.Then the merger characteristics and vibration properties of different dispersion curves are discussed along different directions.The results show that the calculated results are general consistent with available experimental results along high symmetry directions,especially for lower frequency,and the calculated dis-persion curves and experimental dot curves have a very similar shape near high frequency although the actual degree varies somewhat.Along[ζ00]and[ζζζ]directions,two acoustic dispersion curves with different vibration directions AT1 and AT2 merge into a dispersion curve AT.There is no merger phenomenon observed along[ζζ0]direction and low symmetry directions.

关 键 词：声子色散关系 晶格动力学 改进分析型嵌入原子法 

分 类 号：O326[理学—一般力学与力学基础]