#\#CIF_2.0
# Created by the Bilbao Crystallographic Server
# http://www.cryst.ehu.es
# Date: 01/03/2021 

data_5yOhtAoR
_audit_creation_date            2021-03-01
_audit_creation_method          "Bilbao Crystallographic Server"

_citation_journal_abbrev        "Phys. Scr."
_citation_journal_volume        44
_citation_page_first            27
_citation_page_last             32
_citation_article_id            .
_citation_year                  1991
_citation_DOI                   10.1088/0031-8949/44/1/002

loop_
_citation_author_name
"F. Bouree-Vigneron"

_atomic_positions_source_database_code_ICSD  150834
_atomic_positions_source_other               .

_transition_temperature  17
_experiment_temperature  12

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mLD4(k1)  2  1  special  primary  1  .
mLD4(3k1) 2  1  special  secondary 1  no

_exptl_crystal_magnetic_properties_details
;
NPD
Below 10.25K a more complex phase with an additional propagation vector (1/2,1/2,1/2) exists, and it is not fully characterised.
The propagation vector of the structure is incorrectly identified in the article as (0,0,1/4), but the correct one is (0,0,3/4) or (1,0,1/4), which for this parent centred lattice is NOT equivalent.
The structure is modelled by means of a longitudinal sinusoidal wave with a specific initial phase. Probably the data is unsensitive to this phase and other alternative models with different phases could also fit the data. The phase chosen is one of those that keep maximal symmetry.
;

_active_magnetic_irreps_details
;
1k magnetic structure
k-maximal magnetic symmetry
1-dim irrep as primary
A secondary irrep (third harmonic) is symmetry allowed. Its absence makes the two independent moments to be correlated by a factor 2^0.5 through the primary irrep modulation.
At lower temperatures third order satellites are detected, indicating the presence of the secondary irrep and the squaring up of the modulation.
;

_parent_space_group.name_H-M_alt  'I 4/m m m'
_parent_space_group.IT_number                       139
_parent_space_group.transform_Pp_abc  'a,b,c;0,0,0'

loop_
_parent_propagation_vector.id
_parent_propagation_vector.kxkykz
k1 [0 0 3/4]

_parent_space_group.child_transform_Pp_abc  'a,b,4c;0,0,0'
_space_group_magn.transform_BNS_Pp_abc  'a,b,c;0,0,1/4'



_space_group_magn.number_BNS  124.360
_space_group_magn.name_BNS  "P_c 4/m c c"
_cell_length_a             4.03620
_cell_length_b             4.03620
_cell_length_c             39.11160
_cell_angle_alpha          90.00
_cell_angle_beta           90.00
_cell_angle_gamma          90.00

loop_
_space_group_symop_magn_operation.id
_space_group_symop_magn_operation.xyz
1 x,y,z,+1 
2 -y,x,z,+1 
3 y,-x,z,+1 
4 x,-y,-z,+1 
5 -x,y,-z,+1 
6 -x,-y,z,+1 
7 y,x,-z,+1 
8 -y,-x,-z,+1 
9 -x,-y,-z+1/2,+1 
10 y,-x,-z+1/2,+1 
11 -y,x,-z+1/2,+1 
12 -x,y,z+1/2,+1 
13 x,-y,z+1/2,+1 
14 x,y,-z+1/2,+1 
15 -y,-x,z+1/2,+1 
16 y,x,z+1/2,+1 

loop_
_space_group_symop_magn_centering.id
_space_group_symop_magn_centering.xyz
1 x,y,z,+1 
2 x,y,z+1/2,-1 

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Tb1_1 Tb 0.00000 0.00000 0.00000
Tb1_2 Tb  0.50000 0.50000 0.12500
Tb1_3 Tb  0.00000 0.00000 0.25000
Ni1_1 Ni 0.00000 0.50000 0.06250
Ni1_2 Ni  0.50000 0.00000 0.18750
Ge1_1 Ge 0.00000 0.00000 0.09200
Ge1_2 Ge  0.50000 0.50000 0.21700
Ge1_3 Ge  0.50000 0.50000 0.03300
Ge1_4 Ge  0.00000 0.00000 0.34200

loop_
_atom_site_moment.label
_atom_site_moment.crystalaxis_x
_atom_site_moment.crystalaxis_y
_atom_site_moment.crystalaxis_z
_atom_site_moment.symmform
_atom_site_moment.magnitude
Tb1_1 0.00000 0.00000 0.00000 0,0,0   0.0
Tb1_2 0.00000 0.00000 6.22 0,0,mz     6.22
Tb1_3 0.00000 0.00000 -8.8 0,0,mz     8.8

