搜索

x
中国物理学会期刊

R1+εFe4B4化合物中游标卡尺结构对称性表示的两种途径

CSTR: 32037.14.aps.38.1687

TWO APPROACHES TO SYMMETRY REPRESENTATION OF VERNIER STRUCTURE IN R1+εFe4B4 COMPOUNDS

CSTR: 32037.14.aps.38.1687
PDF
导出引用
  • 本文从R1+εFe4B4(ε=0.1)的两个亚结构各自的对称性出发,由两种途径对该化合物的游标卡尺结构对称性进行了描述。结果表明:通过建立公度的长周期超结构模型,可以恢复Rp(Fe4B4)q三维空间对称性,并和p,q的奇偶性组合有关。在p,q同为奇数,p为偶数而q为奇数和p为奇数而q为偶数的情况下,其对称性分别由P42/n,Pccn

     

    The crystal structures of all R1+εFe4B4 compounds are composed of two intepe-netrating tetragonal substructures. and form the Vernier structures. The symmetries of R1+εFe4B4 are characterized by two approaches, those of the space group under the commensurate model Rp(Fe4B4)q and the superspace group. The results indicate that the space gtoup symmetry can be applied to R1+εFe4B4 by constructing a long period superstructure Rp(Fe4B4)q, whose symmetries have been shown to be dependent on the parity of p and q. Space groups P42/n, Pccn, and Ccca(in a revised supercell) can cover the symmetry of Rp(Fe4B4)q for the different parity combinations of p and q, which is in agreement with the experimental results. The supersymmetry of all these compounds can be represented by an orthogonal superspace group PssiCmma. The related systematic extinctions are discussed, and the selection rules of Vernier structures, those can not be explained by three-dimensional space group, are obtained.

     

    目录

    /

    返回文章
    返回
    Baidu
    map