Bilbao Crystallographic Server SYMMODES Classify the Subgroups Help

Classification of the subgroups of type P n a 21(33) of group P n m a(62) with index 2

Choose a subgroup
The following table contains all subgroups Hj= P n a 21(33) of G= P n m a(62) of index 2 distributed into classes of conjugate subgroups.

To view the graph related to one of the subgroups Hj, specify the subgroup and click the corresponding Show graph button.(The first subgroup of every class of conjugate subgroups is checked by default.)

Once the relevant subgroup Hj is chosen, it is possible to specify the crystal structure by selecting the Wyckoff positions of the occupied orbits of atoms.

The complete group - subgroup graph G>H can be viewed from the program


For the group G = P n m a there are 1 different subgroups Hj isomorphic to H = P n a 21 of index 2. These subgroups are distributed in 1 class of conjugate subgroups with respect to the group G.

In the tables below each table corresponds to one class. For each class are given the chains corresponding to the different subgroups in the class, and the obtained transformation matrices.

The list with the chains and transformation matrices that give identical subgroups can be seen by clicking on the button in the column Identical of the table.

Please, select one subgroup.

Class 1

Check Chain [indices] Chain with HM symbols Transformation Identical
1 062 033 [2] P n m a > P n a 21
[     1     0     0 ] [      0]
[     0     0     1 ] [      0]
[     0    -1     0 ] [      0]

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