(b) (x, y), (x, y)
(c) (x, y), (x, y)
(d) (x, y), (x, y)
4. The set of fractional coordinates of equivalent positions related to a 2-fold
rotational symmetry parallel to z-axis in 3-D are:
(a) (x, y, z), (x, y, z)
(b) (x, y, z), (x, y, z)
(c) (x, y, z), (x, y, z)
(d) (x, y, z), (x, y, z)
5. The set of fractional coordinates of equivalent positions related to a 3-fold
rotational symmetry parallel to z-axis in 2-D are:
(a) (x, y), (y, x–y), (y-x, x)
(b) (x, y), (x, y), (x, y)
(c) (x, y), (x, y), (x, y)
(d) (x, y), (x, y), (x, y)
6. The set of fractional coordinates of equivalent positions related to a 4-fold
rotational symmetry parallel to z-axis in 2-D are:
(a) (x, y), (y, x), (y, x), (x, y)
(b) (x, y), (y, x), (x, y), (y, x)
(c) (x, y), (x, y), (x, y), (y, x)
(d) (x, y), (x, y), (x, y) (x, y)
7. The set of fractional coordinates of equivalent positions related to a 6-fold
rotational symmetry parallel to z-axis in 2-D are:
(a) (x, y), (y, x–y), (y-x, x), (x, y), (y-x, x), (y, y-x)
(b) (x, y), (x, y), (y-x, x), (y, y-x), (x, y), (x, y)
(c) (x, y), (x–y, x), (y, x–y), (x, y), (y-x, x), (y, y-x)
(d) (x, y), (x, y), (x, y), (y-x, x), (y, y-x), (x, y)
8. The set of fractional coordinates of equivalent positions related to 2 mm symmetry in 2-D are:
(a) (x, y), (y, x), (y, x), (x, y)
(b) (x, y), (y, x), (x, y), (y, x)
(c) (x, y), (x, y), (x, y), (y, x)
(d) (x, y), (x, y) (x, y), (x, y)
9. The set of fractional coordinates of equivalent positions related to 3 m symmetry
in 2-D are:
(a) (x, y), (y, x–y), (y-x, x), (y, x), (y-x, y), (x, x–y)
(b) (x–y, y), (x, y), (y-x, x), ( y, y-x), (x, y), (x, y)
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3 Unit Cell Calculations