To the right of each space group is a listing of coordinate points. These are
the coordinates to which a general point (x,y,z) is transformed by the space group. Origins (called "equivalent
points" in the International Tables), are additional points around
which the points are transformed. For example, (0,0,0) refers to a corner of the
unit cell, (1/2,1/2,1/2) to the center. All space groups have origin (0,0,0). For
a space group with an additional origin (1/2,1/2,1/2), point (x,y,z) is also transformed
to (1/2+x,1/2+y,1/2+z) and so on.
The six space groups shown here are shown from two vantage points: one along
the two-fold axes and one perpendicular to them. Coordinates are listed for both
orientations.
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10. P2/m
(x,y,z); (x,y,-z); (-x,-y,z); (-x,-y,-z)
P2/m
(x,y,z); (x,-y,z); (-x,y,-z); (-x,-y,-z)
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11. P21/m
(x,y,z); (-x,-y,-z); (-x,-y,1/2+z); (x,y,1/2-z)
P21/m
(x,y,z); (-x,-y,-z); (-x,1/2+y,-z); (x,1/2-y,z)
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12. B2/m
(x,y,z); (x,y,-z); (-x,-y,z); (-x,-y,-z);
Origins: (0,0,0); (1/2,0,1/2)
C2/m
(x,y,z); (x,-y,z); (-x,y,-z); (-x,-y,-z);
Origins: (0,0,0); (1/2,0,1/2)
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13. P2/b
(x,y,z); (-x,-y,-z); (-x,1/2-y,z); (x,1/2+y,-z)
P2/c
(x,y,z); (-x,-y,-z); (-x,y,1/2-z); (x,-y,1/2+z)
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14. P21/b
(x,y,z); (-x,-y,-z); (-x,1/2-y,1/2+z); (x,1/2+y,1/2-z)
P21/c
(x,y,z); (-x,-y,-z); (-x,1/2+y,1/2-z); (x,1/2-y,1/2+z)
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15. B2/b
(x,y,z); (-x,-y,-z); (-x,1/2-y,z); (x,1/2+y,-z);
Origins: (0,0,0); (1/2,0,1/2)
C2/c
(x,y,z); (-x,-y,-z); (-x,y,1/2-z); (x,-y,1/2+z);
Origins: (0,0,0); (1/2,0,1/2)
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