Bilbao Crystallographic Server IDENTIFY GROUP

The program k-SUBGROUPSMAG

Given a space group of a paramagnetic phase (gray group) and a magnetic propagation wave vector, this program calculates all the posible magnetic space subgroups compatible with the propagation vector. The output of the program can be chosen to be the list of subgroups or a subgroup-tree. In both cases the groups are grouped into conjugacy-classes. More information about the conjugacy-classes and the subgroups can be obtained: members of the conjugacy classes, transformation matrix to a standard or reference (default) setting of every group, lists of general positions, etc... All the groups are given in the BNS setting.

Alternative input data.

Instead of the space group of a paramagnetic phase and a magnetic propagation wave-vector, the program allows the following alternative sets of input data:

• Clicking on Choose an alternative magnetic group a general magnetic group can be chosen, introducing its n.m symbol in the BNS setting.
• By default, the program calculates all the subgroups compatible with the input data, being the last subgroup (the subgroup with the lowest symmetry) P1( #1.1) or P_S1 (#1.3). Clicking on Choose the lowest magnetic subgroup to be considered an alternative end subgroup can be chosen.
• The option More wave-vectors needed allows to introduce more than a single propagation wave-vector.
• Checking the box Choose the whole star of the propagation vector(s) the whole set of vectors of the star(s) of the given wave-vectors (with respect to the point group of the given magnetic group) are considered as propagation wave-vectors. For intermediate cases, where a subset of vectors of the star have to be considered, the option Show the independent vectors of the star helps to identify the independent vectors of the star, i.e., those vectors of the star which whose difference does not belong to the reciprocal lattice.
• Instead of a set of propagation wave-vector, a set of basis vectors of the supercell can be given, clicking on Alternatively give the basis vectors of the supercell.

Alternative output.

There are four possible different outputs of the program: the complete (1) list or (2) graph of subgroups compatible with the input data, or the (3) list or (4) graph including only the maximal subgroups.