#\#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        "Acta Cryst. A"
_citation_journal_volume        28
_citation_page_first            580
_citation_page_last             588
_citation_article_id            .
_citation_year                  1972
_citation_DOI                   10.1107/S0567739472001482

loop_
_citation_author_name
"E. F. Bertaut"
"J. Dulac"

_temperature_position_structure         77
_temperature_atom_positions             .
_temperature_non-magn_atom_positions    .
_temperature_cell_parameters            .

_atomic_positions_source_database_code_ICSD  37023
_atomic_positions_source_other               .

_transition_temperature     ?
_experiment_temperature     4.2

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mM4 2 2 general primary 6 .

_exptl_crystal_magnetic_properties_details
;
NPD
Position structure from a determination at 77K by another study
Non-standard parent setting I4_1/amd (origin 1)
Transition temperature is not given
In this phase, two propagation vectors, k=0 and k=(0,0,1) (or equivalently (1,1,1)), are observed. It is not clear if they correspond to two coexisting phases or to a single phase. In this databse, for simplicity, we describe separately the two corresponding magnetic arrangements. That corresponding to k=(1,1,1) is given here.
For the spin arrangement proposed for k=(0,0,0), see #0.895. If the two magnetic propagation vectors are present in a single phase, these two arrangements are superposed on the same system.
;

_active_magnetic_irreps_details
;
1k magnetic structure
k-maximal symmetry
2-dim irrep along a general direction
The MSG label assigned in the paper is incorrect. The correct MSG label in the OG setting that it is used there would be I_p2_12_12_1 (24.4.53).
See #1.685 for a different model, where the same irrep with respect to the tetragonal space group is involved, but restricted to a special direction of higher symmetry, namely P_I4_32_12. The reduction of the MSG to an orthorhombic symmetry being due to the Fddd distortion of the positional structure the present in that model, but not here.
;

_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;0,1/4,-1/8'

loop_
_parent_propagation_vector.id
_parent_propagation_vector.kxkykz
k1 [1 1 1]

_parent_space_group.child_transform_Pp_abc  'a,b,c;0,0,0'
_space_group_magn.transform_BNS_Pp_abc  'a,b,c;0,1/4,-1/8'

_space_group_magn.number_BNS  19.30
_space_group_magn.name_BNS  "P_I 2_1 2_1 2_1"
_space_group_magn.point_group_name  "2221'"
_space_group_magn.point_group_number  "6.2.18"
_cell_length_a                 5.76000
_cell_length_b                 5.76000
_cell_length_c                 8.50000
_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+1/2,-y,-z+3/4,+1 
3 -x,y+1/2,-z+1/4,+1 
4 -x+1/2,-y+1/2,z+1/2,+1 

loop_
_space_group_symop_magn_centering.id
_space_group_symop_magn_centering.xyz
1 x,y,z,+1 
2 x+1/2,y+1/2,z+1/2,-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 0.00000 0.00000 0.00000 1
Cr1_1 Cr 0.00000 0.25000 0.62500 1
Cr1_2 Cr 0.25000 0.50000 0.87500 1
O1_1 O 0.00000 0.23900 0.39200 1
O1_2 O 0.76100 0.50000 0.64200 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 0.0 0.58 0.0 mx,my,0 0.58 ? ?
Cr1_1 0.0 0.73 -0.45 0,my,mz ? ? ?
Cr1_2 0.0 0.0 0.86 mx,0,mz ? ? ?

