#\#CIF_2.0
# Created by the Bilbao Crystallographic Server
# http://www.cryst.ehu.es
# Date: 10/30/2020

data_5yOhtAoR
_audit_creation_date            2020-10-30
_audit_creation_method          "Bilbao Crystallographic Server"

_chemical_name_common                    ?
_chemical_formula_moiety                 ?
_chemical_formula_structural             ?
_chemical_formula_analytical             ?
_chemical_formula_iupac                  ?
_chemical_formula_sum                    "Gd2 Ba Cu O5"
_chemical_formula_weight                 ?
_chemical_melting_point                  ?
_chemical_compound_source                ?
_chemical_absolute_configuration         ?


_citation_journal_abbrev        "PHYSICAL REVIEW RESEARCH"
_citation_journal_volume        2
_citation_page_first            ?
_citation_page_last             ?
_citation_article_id            023271
_citation_year                  2020
_citation_DOI                   10.1103/PhysRevResearch.2.023271

loop_
_citation_author_name
"P. Yanda"
"I.V. Golosovsky"
"I. Mirebeau"
"N.V. Ter-Oganessian"
"J. Rodriguez-Carvajal"
"A. Sundaresan"




_atomic_positions_source_database_code_ICSD  .
_atomic_positions_source_other               .

_transition_temperature     11.8
_experiment_temperature     9.8

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mLD2 2 1 general primary 12 .
mLD3 2 1 special primary 12 .


_exptl_crystal_magnetic_properties_details
;
NPD
Position structure (except lattice parameters) from a determination at room temperature.
Below 6K a lock-in phase exists with a commensurate propagation vector k=(0 0 1/2) and the 2-dim irrep mZ2 along a special direction as the active irrep.
;

_active_magnetic_irreps_details
;
1k incommensurate magnetic structure
Two 2-dim irreps are involved as primary. They are combined in quadrature, with a pi/2 relative shift of their spin waves.
The active irreps mLD2 and mLD3 in this phase are the two irreps compatible with the irrep mZ2 at the limit of the lock-in commensurate k-vector (0 0 1/2), which is the irrep relevant for the lock-in structure.
Polar symmetry along a. Type II multiferroic (spin driven ferroelectricity along a).
The present model varies from the one reported in the original article. It has a higher symmetry given by an orthorhombic magnetic superspace group, which is a supergroup of the monoclinic group considered in the article. The structure here is in accordance with the planned corrigendum of the article (private communication from J. Rodriguez-Carvajal).
;

_parent_space_group.name_H-M_alt  "P n m a"
_parent_space_group.IT_number             62
_parent_space_group.transform_Pp_abc  "a,b,c;0,0,0"

_cell_modulation_dimension               1

loop_
_cell_wave_vector_seq_id
_cell_wave_vector_x
_cell_wave_vector_y
_cell_wave_vector_z
1 0.00000 0.00000 0.44490


_parent_space_group.child_transform_Pp_abc  "a,b,c;0,0,0"

_space_group.magn_ssg_name  "P2_1ma1'(0,0,g)0s0s"
_space_group.magn_point_group_name  "mm21'"
_space_group.magn_point_group_number  7.2.21
_cell_length_a                 12.2282
_cell_length_b                 5.67992
_cell_length_c                 7.16183
_cell_angle_alpha              90.0000
_cell_angle_beta               90.0000
_cell_angle_gamma              90.0000

loop_
_space_group_symop_magn_ssg_operation.id
_space_group_symop_magn_ssg_operation.algebraic
1 x1,x2,x3,x4,1
2 x1+1/2,-x2+1/2,-x3+1/2,-x4,1
3 x1,-x2+1/2,x3,x4+1/2,1
4 x1+1/2,x2,-x3+1/2,-x4+1/2,1

loop_
_space_group_symop_magn_ssg_centering.id
_space_group_symop_magn_ssg_centering.algebraic
1 x1,x2,x3,x4,1
2 x1,x2,x3,x4+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
Gd1_1 Ho 0.28860 0.25000 0.11560 1
Gd1_2 Ho 0.71140 0.75000 0.88440 1
Gd2_1 Ho 0.07380 0.25000 0.39540 1
Gd2_2 Ho -0.0738 0.75000 0.60460 1
Cu_1 Cu 0.65920 0.25000 0.71290 1
Cu_2 Cu 0.34080 0.75000 0.28710 1
Ba1_1 Ba 0.90560 0.25000 0.9313 1
Ba1_2 Ba  0.59440 0.75000 0.4313 1
O1_1 O 0.43250 0.98800 0.1705  1
O1_2 O  0.06750 0.01200 0.6705 1
O2_1 O 0.22510 0.50500 0.345  1
O2_2 O  0.27490 0.49500 0.845 1
O3_1 O 0.09400 0.25000 0.069  1
O3_2 O  0.40600 0.75000 0.569 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
Gd1_1 0.00000 0.00000 0.00000 0,0,0
Gd1_2 0.00000 0.00000 0.00000 0,0,0
Gd2_1 0.00000 0.00000 0.00000 0,0,0
Gd2_2 0.00000 0.00000 0.00000 0,0,0
Cu_1 0.00000 0.00000 0.00000 0,0,0
Cu_2 0.00000 0.00000 0.00000 0,0,0

loop_
_atom_site_Fourier_wave_vector.seq_id
_atom_site_Fourier_wave_vector.q1_coeff
1 1

loop_
_atom_site_moment_Fourier.atom_site_label
_atom_site_moment_Fourier.axis
_atom_site_moment_Fourier.wave_vector_seq_id
_atom_site_moment_Fourier_param.cos
_atom_site_moment_Fourier_param.sin
_atom_site_moment_Fourier_param.cos_symmform
_atom_site_moment_Fourier_param.sin_symmform
Gd1_1 x 1 -2.775(13) 0.367   mxc1 mxs1
Gd1_1 y 1 0.00000 0.00000      0    0
Gd1_1 z 1 3.73(4) 5.631(18)    mzc1 mzs1
Gd1_2 x 1 5.496(15) 1.172(4)   mxc1 mxs1
Gd1_2 y 1 0.00000 0.00000      0    0
Gd1_2 z 1 2.583(11) 0.115    mzc1 mzs1
Gd2_1 x 1 0.848 2.019(6)        mxc1 mxs1
Gd2_1 y 1 0.00000 0.00000      0    0
Gd2_1 z 1 2.898(4) -7.11(8)    mzc1 mzs1
Gd2_2 x 1 -4.950(12) 2.301(9)  mxc1 mxs1
Gd2_2 y 1 0.00000 0.00000      0    0
Gd2_2 z 1 -1.25(2) 1.454(7)    mzc1 mzs1
Cu_1 x 1 0.070 -0.168           mxc1 mxs1
Cu_1 y 1 0.00000 0.00000       0    0
Cu_1 z 1 0.998 0.914(6)        mzc1 mzs1
Cu_2 x 1 0.735 0.481           mxc1 mxs1
Cu_2 y 1 0.00000 0.00000       0    0
Cu_2 z 1 0.182 -0.877(5)       mzc1 mzs1

