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<pre>
Result of symbol lookup:
  Space group number: 74
  Schoenflies symbol: D2h^28
  Hermann-Mauguin symbol: I m m a
  Hall symbol: -I 2b 2

Input space group symbol: I m m a
Convention: Default

Number of lattice translations: 2
Space group is centric.
Number of representative symmetry operations: 4
Total number of symmetry operations: 16

Parallelepiped containing an asymmetric unit:
  0&lt;=x&lt;=1/4; 0&lt;=y&lt;=1/4; 0&lt;=z&lt;1

List of symmetry operations:
</pre><table border=2 cellpadding=2>
<tr>
<th>Matrix
<th>Rotation-part type
<th>Axis direction
<th>Screw/glide component
<th>Origin shift
</tr>
<tr>
<td><tt>x,y,z</tt>
<td>1<td>-<td>-<td>-
</tr>
<tr>
<td><tt>-x,-y+1/2,z</tt>
<td>2<td>[0,0,1]<td>0,0,0<td>0,1/4,0
</tr>
<tr>
<td><tt>x,-y,-z</tt>
<td>2<td>[1,0,0]<td>0,0,0<td>0,0,0
</tr>
<tr>
<td><tt>-x,y+1/2,-z</tt>
<td>2<td>[0,1,0]<td>0,1/2,0<td>0,0,0
</tr>
<tr>
<td><tt>-x,-y,-z</tt>
<td>-1<td>-<td>-<td>0,0,0
</tr>
<tr>
<td><tt>x,y-1/2,-z</tt>
<td>-2<td>[0,0,1]<td>0,-1/2,0<td>0,0,0
</tr>
<tr>
<td><tt>-x,y,z</tt>
<td>-2<td>[1,0,0]<td>0,0,0<td>0,0,0
</tr>
<tr>
<td><tt>x,-y-1/2,z</tt>
<td>-2<td>[0,1,0]<td>0,0,0<td>0,-1/4,0
</tr>
<tr>
<td><tt>x+1/2,y+1/2,z+1/2</tt>
<td>1<td>-<td>-<td>-
</tr>
<tr>
<td><tt>-x+1/2,-y+1,z+1/2</tt>
<td>2<td>[0,0,1]<td>0,0,1/2<td>1/4,1/2,0
</tr>
<tr>
<td><tt>x+1/2,-y+1/2,-z+1/2</tt>
<td>2<td>[1,0,0]<td>1/2,0,0<td>0,1/4,1/4
</tr>
<tr>
<td><tt>-x+1/2,y+1,-z+1/2</tt>
<td>2<td>[0,1,0]<td>0,1,0<td>1/4,0,1/4
</tr>
<tr>
<td><tt>-x+1/2,-y+1/2,-z+1/2</tt>
<td>-1<td>-<td>-<td>1/4,1/4,1/4
</tr>
<tr>
<td><tt>x+1/2,y,-z+1/2</tt>
<td>-2<td>[0,0,1]<td>1/2,0,0<td>0,0,1/4
</tr>
<tr>
<td><tt>-x+1/2,y+1/2,z+1/2</tt>
<td>-2<td>[1,0,0]<td>0,1/2,1/2<td>1/4,0,0
</tr>
<tr>
<td><tt>x+1/2,-y,z+1/2</tt>
<td>-2<td>[0,1,0]<td>1/2,0,1/2<td>0,0,0
</tr>
</table><pre>

List of Wyckoff positions:
</pre><table border=2 cellpadding=2>
<tr>
<th>Wyckoff letter
<th>Multiplicity
<th>Site symmetry<br>point group type
<th>Representative special position operator
</tr>
<tr>
<td>j<td>16<td>1<td><tt>x,y,z</tt>
</tr>
<tr>
<td>i<td>8<td>m<td><tt>x,1/4,z</tt>
</tr>
<tr>
<td>h<td>8<td>m<td><tt>0,y,z</tt>
</tr>
<tr>
<td>g<td>8<td>2<td><tt>1/4,y,1/4</tt>
</tr>
<tr>
<td>f<td>8<td>2<td><tt>x,0,0</tt>
</tr>
<tr>
<td>e<td>4<td>mm2<td><tt>0,1/4,z</tt>
</tr>
<tr>
<td>d<td>4<td>2/m<td><tt>1/4,1/4,-1/4</tt>
</tr>
<tr>
<td>c<td>4<td>2/m<td><tt>1/4,1/4,1/4</tt>
</tr>
<tr>
<td>b<td>4<td>2/m<td><tt>0,0,1/2</tt>
</tr>
<tr>
<td>a<td>4<td>2/m<td><tt>0,0,0</tt>
</tr>
</table><pre>

Harker planes:
</pre><table border=2 cellpadding=2>
<tr>
<th>Algebraic
<th>Normal vector
<th>A point in the plane
</tr>
<tr>
<td><tt>2*x,2*y+1/2,0</tt><td>[0,0,1]<td>0,1/2,0
</tr>
<tr>
<td><tt>0,2*y,2*z</tt><td>[1,0,0]<td>0,0,0
</tr>
<tr>
<td><tt>2*x,1/2,2*z</tt><td>[0,1,0]<td>0,1/2,0
</tr>
</table><pre>

Additional generators of Euclidean normalizer:
  Number of structure-seminvariant vectors and moduli: 2
    Vector    Modulus
    (1, 0, 0) 2
    (0, 1, 0) 2

Grid factors implied by symmetries:
  Space group: (2, 2, 2)
  Structure-seminvariant vectors and moduli: (2, 2, 1)
  Euclidean normalizer: (2, 2, 2)

  All points of a grid over the unit cell are mapped
  exactly onto other grid points only if the factors
  shown above are factors of the grid.

</pre>
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