#\#CIF_2.0
# Created by the Bilbao Crystallographic Server
# http://www.cryst.ehu.es
# Date: 10/16/2022

data_5yOhtAoR
_audit_creation_date            2022-10-16
_audit_creation_method          "Bilbao Crystallographic Server"

_chemical_name_systematic
;
;
_chemical_name_common                    ?
_chemical_formula_moiety                 ?
_chemical_formula_structural             ?
_chemical_formula_analytical             ?
_chemical_formula_iupac                  ?
_chemical_formula_sum                    "Ni1 Cr2 O4"
_chemical_formula_weight                 ?
_chemical_melting_point                  ?
_chemical_compound_source                ?
_chemical_absolute_configuration         ?

_citation_journal_abbrev        "PHYSICAL REVIEW B?"
_citation_journal_volume        91
_citation_page_first            .
_citation_page_last             .
_citation_article_id            024407
_citation_year                  2015
_citation_DOI                   10.1103/PhysRevB.91.024407

loop_
_citation_author_name
"M. Reehuis"
"M. Tovar"
"D. M. Tobbens"
"P. Pattison"
"A. Hoser"
"B. Lake"

_temperature_position_structure         2
_temperature_atom_positions             .
_temperature_non-magn_atom_positions    .
_temperature_cell_parameters            .

_atomic_positions_source_database_code_ICSD  241305
_atomic_positions_source_other               .

_transition_temperature     74
_experiment_temperature     36

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mGM5+ 2 2 special primary 4 .

_exptl_crystal_magnetic_properties_details
;
NPD
Position structure from a determination at 2K
Below 24K another more complex magnetic phase exists
The structure has a very small structural distortion which lowers the efective space group from I4_1/amd to Fddd. As this structural distortion is simultaneous with the magnetic ordering and consistent with the resulting MSG, it can be considered an induced effect, and we keep here the tetragonal space group as the parent symmetry.
The magnetic structure is described in the paper within the Fddd setting, and this description is mantained here.
The direction of the collinear moments on the plane xy, perpendiculat to the parent tetragonal axis, is undetermined. It is assumed to be along x (Fddd setting), for consistency with the weak induced Fddd structural distortion.
Ferrimagnetic along x (Fddd setting) or direction (1,-1,0) in the parent tetragonal setting
The FI direction is on the tetragonal basal plane, while in CuCr2O4, reported in the same paper, although it is also along the x direction of the Fddd setting used, this direction in this second case corresponds to the parent tetragonal axis (see #0.891)
;

_active_magnetic_irreps_details
;
1k magnetic structure
k-maximal magnetic symmetry
2-dim irrep along a special direction
;

_parent_space_group.name_H-M_alt  'I 4_1/a m d'
_parent_space_group.IT_number                       141
_parent_space_group.transform_Pp_abc  'a,b,c;0,0,0'

loop_
_parent_propagation_vector.id
_parent_propagation_vector.kxkykz
k1 [0 0 0]

_parent_space_group.child_transform_Pp_abc  'a-b,a+b,c;1/4,3/4,1/4'
_space_group_magn.transform_BNS_Pp_abc  'c,b,-a;0,1/4,1/4'

_space_group_magn.number_BNS  70.530
_space_group_magn.name_BNS  "F d' d' d"
_space_group_magn.point_group_name  "m'm'm"
_space_group_magn.point_group_number  "8.4.27"
_cell_length_a                 8.1661
_cell_length_b                 8.1794
_cell_length_c                 8.5623
_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 x,-y+1/4,-z+1/4,+1 
3 -x,-y+1/2,-z+1/2,+1 
4 -x,y+1/4,z+1/4,+1 
5 -x+1/4,-y+1/4,z,-1 
6 -x+1/4,y,-z+1/4,-1 
7 x+3/4,y+1/4,-z+1/2,-1 
8 x+3/4,-y+1/2,z+1/4,-1 

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

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Ni1 Ni 0.12500 0.12500 0.12500 1
Cr1 Cr 0.50000 0.50000 0.50000 1
O1 O 0.2572 0.2580 0.2681 1

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
_atom_site_moment.spherical_azimuthal
_atom_site_moment.spherical_polar
Ni1 -1.69(10) 0.0 0.0 mx,0,0 1.69(10) ? ?
Cr1 0.84(8) 0.0 0.0 mx,my,mz 0.84(8) ? ?

