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

data_5yOhtAoR
_audit_creation_date            2020-05-15
_audit_creation_method          "Bilbao Crystallographic Server"

_citation_journal_abbrev        "npj Quantum Materials"
_citation_journal_volume        5
_citation_page_first            ?
_citation_page_last             ?
_citation_article_id            23
_citation_year                  2020
_citation_DOI                   10.1038/s41535-020-0222-8

loop_
_citation_author_name
"R.W. Smaha"
"W. He"
"J.M. Jiang"
"J. Wen"
"Y.-F. Jiang"
"J.P. Sheckelton"
"C.J. Titus"
"S.G. Wang"
"Y.-S. Chen"
"S.J. Teat"
"A.A. Aczel"
"Y. Zhao"
"G. Xu"
"J.W. Lynn"
"H.-C. Jiang"
"Y.S. Lee"



_atomic_positions_source_database_code_ICSD  .
_atomic_positions_source_other               .

_transition_temperature     6
_experiment_temperature     2.7

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mGM4+GM6+ 2  2 general primary ? .
mGM2+ 1  1   .  secondary? ? yes

_exptl_crystal_magnetic_properties_details
;
NSD
Hexagonal Polymorph
Position structure from a determination at 15K
The moments of Cu split sites with partial occupancies, are assumed equal
;

_active_magnetic_irreps_details
;
1k magnetic structure
FM on the ab plane
Except for some signs of the spin cantings out of the ab plane and the moments at the Cu3 sites, the structure has the higher symmetry P6_3'/m', which corresponds to the irrep mGM2+. A model constrained to this higher symmetry was apparently not tried in the refinement, as FM was observed in macroscopic measurements.
The small deviation from P6_3'/m' symmetry is associated with the (physically irreducible) irrep mGM4+GM6+, which lowers the symmetry to the monoclinic MSG P2_1'/m'.
Although formally mGM4+GM6+ is the primary irrep yielding the observed symmetry break with respect to the paramagnetic symmetry, the mGM2+ distortion cannot be considered a secondary effect, but rather an independent primary order parameter distortion, as it is dominant in the model.
The prevalence of the P6_3'/m' arrangement in the structure suggests the existence of a previous phase transition into this higher symmetry. The  existence of two phase transitions separated by a few degrees, mentioned in the reference, could be related with this possible two order parameters mechanism with two transitions.
;

_parent_space_group.name_H-M_alt  "P 63/m"
_parent_space_group.IT_number                      176
_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,c;0,0,0"
_space_group_magn.transform_BNS_Pp_abc  "b,c,a;0,0,0"


_space_group_magn.number_BNS   11.54
_space_group_magn.name_BNS     "P 2_1'/m'"
_cell_length_a                 13.3208
_cell_length_b                 13.3208
_cell_length_c                 9.2662
_cell_angle_alpha              90
_cell_angle_beta               90
_cell_angle_gamma              120

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+1/2,-1
4 x,y,-z+1/2,-1

loop_
_space_group_symop_magn_centering.id
_space_group_symop_magn_centering.xyz
1 x,y,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
Cu1_1 Cu 0.50001 0.25046 0.5 1
Cu1_2 Cu -0.25046 0.24955 0.5 1
Cu1_3 Cu -0.24955 -0.50001 0.5 1
Cu2_1 Cu 0.24982 0.25019 0.49711 1
Cu2_2 Cu -0.25019 -0.00037 0.49711 1
Cu2_3 Cu 0.00037 -0.24982 0.49711 1
Cu3_1 Cu 0.37139 0.68572 0.25 0.3333
Cu3_2 Cu -0.68572 -0.31433 0.25 0.3333
Cu3_3 Cu 0.31433 -0.37139 0.25 0.3333
Cu4_1 Cu 0.31422 0.18552 0.25 0.2396
Cu4_2 Cu -0.18552 0.1287 0.25 0.2396
Cu4_3 Cu -0.1287 -0.31422 0.25 0.2396
Cu5_1 Cu 0.31438 0.12857 0.25 0.4274
Cu5_2 Cu -0.12857 0.18581 0.25 0.4274
Cu5_3 Cu -0.18581 -0.31438 0.25 0.4274
Cu6_1 Cu 0.37143 0.18552 0.25 0.334
Cu6_2 Cu -0.18552 0.18591 0.25 0.334
Cu6_3 Cu -0.18591 -0.37143 0.25 0.334
Br1_1 Br 0.66668 0.83382 0.25 1
Br1_2 Br -0.83382 -0.16714 0.25 1
Br1_3 Br 0.16714 -0.66668 0.25 1
Br2 Br 0.666667 0.333333 0.25 1
F1_1 F 0.50082 0.50085 0.25 1
F1_2 F -0.50085 -0.00003 0.25 1
F1_3 F 0.00003 -0.50082 0.25 1
F2 F 0 0 0.25 1
O1_1 O 0.60111 0.39932 0.59179 1
O1_2 O -0.39932 0.20179 0.59179 1
O1_3 O -0.20179 -0.60111 0.59179 1
O2_1 O 0.3989 0.10113 0.40759 1
O2_2 O -0.10113 0.29777 0.40759 1
O2_3 O -0.29777 -0.3989 0.40759 1
O3_1 O 0.39919 0.29845 0.40882 1
O3_2 O -0.29845 0.10074 0.40882 1
O3_3 O -0.10074 -0.39919 0.40882 1
O4_1 O 0.20187 0.10024 0.40823 1
O4_2 O -0.10024 0.10163 0.40823 1
O4_3 O -0.10163 -0.20187 0.40823 1
H1_1 H 0.5527 0.4272 0.628 1
H1_2 H -0.4272 0.1255 0.628 1
H1_3 H -0.1255 -0.5527 0.628 1
H2_1 H 0.4502 0.072 0.377 1
H2_2 H -0.072 0.3782 0.377 1
H2_3 H -0.3782 -0.4502 0.377 1
H3_1 H 0.428 0.3754 0.375 1
H3_2 H -0.3754 0.0526 0.375 1
H3_3 H -0.0526 -0.428 0.375 1
H4_1 H 0.1243 0.0516 0.37 1
H4_2 H -0.0516 0.0727 0.37 1
H4_3 H -0.0727 -0.1243 0.37 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
Cu1_1 -0.03 0.12 0.08 mx,my,mz
Cu1_2 -0.14 -0.17 0.0 mx,my,mz
Cu1_3 0.15 0.03 -0.08 mx,my,mz
Cu2_1 -0.10 -0.26 0.0 mx,my,mz
Cu2_2 0.23 0.14 -0.11 mx,my,mz
Cu2_3 -0.14 0.09 0.11 mx,my,mz
Cu3_1 -0.14 -0.12 0.0 mx,my,0
Cu3_2 -0.14 -0.12 0.0 mx,my,0
Cu3_3 -0.14 -0.12 0.0 mx,my,0
Cu4_1 0.15 0.075 0.0 mx,my,0
Cu4_2 -0.075 0.075 0.0 mx,my,0
Cu4_3 -0.075 -0.15 0.0 mx,my,0
Cu5_1 0.15 0.075 0.0 mx,my,0
Cu5_2 -0.075 0.075 0.0 mx,my,0
Cu5_3 -0.075 -0.15 0.0 mx,my,0
Cu6_1 0.15 0.075 0.0 mx,my,0
Cu6_2 -0.075 0.075 0.0 mx,my,0
Cu6_3 -0.075 -0.15 0.0 mx,my,0


