GBasIReps
The GUI to BasIReps has the following important fields that are used to generate input, "codefile.smb", and output files (after running BasIReps from the corresponding menu or button): "codefile.bsr" and "codefile.fp".
Code of files
Common code of files for the run
Working Directory
Complete path name of the working directory. This may be selected using the Browse button.
Title
A character string used as a title for the run
SpaceGroup or generators
A character string with different meanings. The user may input different things:
Example: x,-y,z+1/2 ; -x,y,z ; -x,-y,-z
K-vector
Components of the propagation vector in reciprocal lattice units.
The reciprocal basis vectors are defined, through the well known dual relations, using direct basis vector of the conventional unit cell. This is the common practice in diffraction physics and crystallography.
Warning: The components of k-vectors in most textbooks of group theory are given with respect to the reciprocal basis of the primitive direct basis vectors. For primitive Bravais lattices there is no problem.
Brillouin Zone Label
Whatever character used for identification purposes. Up to two letters!
Example: GG
Polar vector/Axial vector
Checking one of the two alternatives will select the behaviour of the symmetry operators upon acting on vectors.
Number of atoms
Number of atoms.
Explicit Sublattices
The "Number of atoms" coincides with the number of sites (NS). The program will generate automatically all sublattices and, eventually, modify the number of sites if the propagation vector group cannot connect part of the sublattices generated by the full space group. The "Symbol" of the atom should have a maximum of four characters. Usually the chemical symbol is enough. The fractional coordinates are given in the fields "x/a", "x/b", "x/c". The GUI generates NS ATOM lines.
The "Number of atoms" is really the total number of atoms in the unit cell. In this case the name of the atoms cannot be arbitrarily given. For a particular site they must share the same atom code and the different sublattices are distinguished by an added underscore "_" followed by the number of the sublattice. The GUI generates a list of SUBL block of lines, deduced from the "Symbol". For example, to generate the SUBL blocks in the example of SUBL keyword above we have to write Number of atoms = 8, check the "Explicit Sublattices" box and provide the list:
Tb_1 0.00000 0.00000 0.50000
Tb_2 0.25000 0.75000 0.75000
Tb_3 0.50000 0.00000 0.00000
Tb_4 0.25000 0.25000 0.25000
Fe_1 0.00000 0.00000 0.00000
Fe_2 0.50000 0.00000 0.50000
Fe_3 0.75000 0.25000 0.75000
Fe_4 0.75000 0.75000 0.25000
BE CAREFUL! if the provided sublattices do not correspond are not related by operators in the propagation vector group (little group) the obtained results are wrong! If you are not sure it is safer to use the first atom of sites and let the program generate the sublattices.
Atoms in unit cell
If this box is checked the program will put all generated atoms within the reference cell all coordinates values (v) verifying 0.0 <= v < 1.0.
NOTE: This is only operative if the box "Explicit Sublattices" is not checked.
FullProf Suite 2010