#\#CIF_2.0
# Created by the Bilbao Crystallographic Server
# http://www.cryst.ehu.es
# Date: 11/19/2017 17:03:52
# Database entry: 1.0.1 Ag2CrO2
# Cif-like file for the case 1.0.1


data_5yOhtAoR
_audit_creation_date            2017-11-19
_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                    'Ag2 Cr O2'
_chemical_formula_weight                 ?
_chemical_melting_point                  ?
_chemical_compound_source                ?
_chemical_absolute_configuration         .


_citation_journal_abbrev        "PHYSICAL REVIEW B"
_citation_journal_volume        85
_citation_page_first            ?
_citation_page_last             ?
_citation_article_id            144407
_citation_year                  2012
_citation_DOI                   10.1103/physrevb.85.144407

loop_
_citation_author_name
"M. Matsuda"
"C. de la Cruz"
"H. Yoshida"
"M. Isobe"
"R.S. Fishman"





_atomic_positions_source_database_code_ICSD  .
_atomic_positions_source_other               .

_transition_temperature     24
_experiment_temperature     4

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mLD2(k1) 6 1 . primary ? ?
mLD1(k2) 6 1 . secondary ? ?

_exptl_crystal_magnetic_properties_details
;
NPD
Reported weak ferromagnetism is not compatible with the magnetic structure. FM not allowed by its symmetry.
Partial disordered sites symmetry-forced.

The reported simultaneous structural transition is in fact part of the magnetic symmetry break, i.e. an induced effect. The magnetic ordering decreases the effective space group for the nuclear positions to C2/m, with same unit cell as the magnetic cell. Expected primary  modulations for the nuclear positions with wave vector (2/5,2/5,0). The reported C2/m nuclear structure is an average structure with a cell five times smaller. The reference disregards the allowed modulation of nuclear positions.

The reference reports magnetic reflections of type (4/5, 1/5, L) which are not consistent with the magnetic structure proposed.

The equality of the moments of the two independent Cr sites of the model requires the presence of a third harmonic in the spin modulation with propagation vector (2/5, 2/5, 0). Satellites of this type not reported in the reference.
;

_active_magnetic_irreps_details
;
1k magnetic structure
k-maximal magnetic symmetry
;

_parent_space_group.name_H-M_alt  'P  -3m  1'
_parent_space_group.IT_number                       164
_parent_space_group.transform_Pp_abc  'a,b,c;0,0,0'

loop_
_parent_propagation_vector.id
_parent_propagation_vector.kxkykz
k1 [1/5 1/5 0]
k2 [2/5 2/5 0]

_parent_space_group.child_transform_Pp_abc  'a-b,-5a-5b,-c;0,0,0'
_space_group_magn.transform_BNS_Pp_abc  'a,b,c;0,0,0'


_space_group_magn.number_BNS  12.60
_space_group_magn.name_BNS  "C  2'/m"
_space_group_magn.point_group_name  "2'/m"
_space_group_magn.point_group_number  "5.3.14"
_cell_length_a                 5.07976(16)
_cell_length_b                 14.58493(4)
_cell_length_c                 8.66164(2)
_cell_angle_alpha              90.00
_cell_angle_beta               90.0723(3)
_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,z,+1
3 -x,y,-z,-1
4 -x,-y,-z,-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

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Ag1 Ag 0.8375 0.90000 0.3719 1
Ag2 Ag 0.3375 0.80000 0.3719 1
Ag3 Ag 0.3375(11) 0.00000 0.3719(4) 1
Cr1 Cr 0.00000 0.00000 0.00000 1
Cr2 Cr 0.00000 0.40000 0.00000 1
Cr3 Cr 0.00000 0.80000 0.00000 1
O1 O 0.8309 0.90000 0.1195 1
O2 O 0.3309 0.80000 0.1195 1
O3 O 0.3309(12) 0.00000 0.1195(4) 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
Cr1 0 0 0 0,0,0
Cr2 0.0 0.0 2.9(1) mx,0,mz
Cr3 0.0 0.0 2.9(1) mx,0,mz

