标题: Symmetry Operation [打印本页] 作者: OLS 时间: 2009-2-2 22:45 标题: Symmetry Operation Symmetry Operation * |( T3 C, m7 LSymmetry operations include the Improper Rotation, Inversion Operation, Mirror Plane, and Rotation. Together, these operations create 32 crystal classes corresponding to the 32 Point Groups. " I3 I; J; l/ E
The Inversion Operation takes 0 J6 Z- O9 M2 h2 ~+ g& K$ M
(x,y,z)=>(-x,-y,-z) 2 d4 s' b: ^* O o( }2 V" f% } and is denoted i. When used in conjunction with a Rotation, it becomes an Improper Rotation. An Improper Rotation by 360/n . For periodic crystals, the Crystallography Restriction allows only the Improper Rotations 1, 2, 3, 4, and 6. ) S* W' l4 G2 O5 v8 QThe Mirror Plane symmetry operation takes " H* F8 @8 t+ \/ H9 B
(x,y,z)=>(x,y,-z)=>(x,-y,z) ' O3 e: ^3 Z# n9 tetc., which is equivalent to 2.