Symmetry Operation + [" ?2 ?, s+ ?; g1 Z2 M: ISymmetry operations include the Improper Rotation, Inversion Operation, Mirror Plane, and Rotation. Together, these operations create 32 crystal classes corresponding to the 32 Point Groups. 2 u+ p+ C! t }4 m* S% ^
The Inversion Operation takes ' k' ]7 s9 r3 d(x,y,z)=>(-x,-y,-z) : |0 ~0 X8 g% D9 O, {: [( `, Q. L 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. 4 E7 H+ E) D+ Q- N3 j
The Mirror Plane symmetry operation takes & c, y' w! n+ K+ M4 m2 g; _(x,y,z)=>(x,y,-z)=>(x,-y,z) - l, c$ O1 F4 y1 Y) {1 ~etc., which is equivalent to 2.