39. The order of cubic point group T h ðm3) is:
(a) 24
(b) 18
(c) 12
(d) 6
40. The order of cubic point group O h ðm3m) is:
(a) 12
(b) 24
(c) 36
(d) 48
41. The symmetry elements E, C 2 , r xz and r yz belong to the point group:
(a) C 2v (mm2)
(b) C 2h (2/m)
(c) D 2 (222)
(d) D 2h (mmm)
42. The symmetry elements E; C 2 , r h and i belong to the point group:
(a) C 2v (mm2)
(b) C 2h (2/m)
(c) D 2 (222)
(d) D 2h (mmm)
43. The symmetry elements E, C 2x , C 2y and C 2z belong to the point group:
(a) C 2v (mm2)
(b) C 2h (2/m)
(c) D 2 (222)
(d) D 2h (mmm)
44. The symmetry elements E, C 2x , C 2y , C 2z , i, r x , r y , and r z belong to the point
group:
(a) C 2v (mm2)
(b) C 2h (2/m)
(c) D 2 (222)
(d) D 2h (mmm)
45. The symmetry elements E, C 4 ; C
2
4 ; C
3
4 ; r x ; r y ; r 1 and r 2 belong to the point
group:
(a) C 4v (4 mm)
(b) C 4h (4/m)
(c) D 4 (422)
(d) D 2d ( 42m)
260
6 Unit Cell Symmeteries and Their Representations