#\#CIF_2.0
# Created by the Bilbao Crystallographic Server
# http://www.cryst.ehu.es
# Date: 09/22/2019

data_5yOhtAoR
_audit_creation_date            2019-09-22
_audit_creation_method          "Bilbao Crystallographic Server"


_citation_journal_abbrev        "Z. Phys. B - Condensed Matter"
_citation_journal_volume        77
_citation_page_first            95
_citation_page_last             104
_citation_article_id            ?
_citation_year                  1989
_citation_DOI                   10.1007/BF01313625

loop_
_citation_author_name
"G. Knopp"
"A. Loidl"
"K. Knorr"
"L. Pawlak"
"M. Duczmal"
"R. Caspary"
"U. Gottwick"
"H. Spille"
"F. Steglich"
"A.P. Murani"




_atomic_positions_source_database_code_ICSD  52848
_atomic_positions_source_other               .

_transition_temperature     4.1
_experiment_temperature     1.5

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mA1 8 1 . primary 1 .
mA2 8 1 . primary 2 .

_exptl_crystal_magnetic_properties_details
;
NPD
The model is a circular spin spiral with the plane of the spin rotation perpendicular to the propagation vector
The spin modulation components are here only approximate to reproduce the spin modulus, and also the perpendicularity of the spiral plane with respect to the propagation vector, which is not forced by symmetry.
;

_active_magnetic_irreps_details
;
1k incommensurate magnetic structure
The two possible irreps are involved with a pi/2 shift
The 2-fold symmetry of the structure is along the (1,-1,0) direction.
The MSSG only forces that the plane of the spin rotation includes the (1,-1,0) direction, and allows ellipcity of the spin rotation.
;

_parent_space_group.name_H-M_alt  "I 4/m m m"
_parent_space_group.IT_number             139
_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 0.280000 0.280000 0.540000


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

_space_group.magn_ssg_name  "I21'(a,a,g)0s"
_space_group.magn_point_group_name  "21'"
_space_group.magn_point_group_number  3.2.7
_cell_length_a                 4.158
_cell_length_b                 4.158
_cell_length_c                 10.227
_cell_angle_alpha              90
_cell_angle_beta               90
_cell_angle_gamma              90

loop_
_space_group_symop_magn_ssg_operation.id
_space_group_symop_magn_ssg_operation.algebraic
1 x1,x2,x3,x4,+1
2 -x2,-x1,-x3,-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+1/2,x2+1/2,x3+1/2,x4,+1
3 x1,x2,x3,x4+1/2,-1
4 x1+1/2,x2+1/2,x3+1/2,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
Ce1 Ce 0 0 0 1
Cu1_1 Cu 0 0.5 0.25 1
Cu1_2 Cu 0 -0.5 -0.25 1
Ge1 Ge 0 0 0.385 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
Ce1 0 0 0 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
Ce1 x 1 0.25 0.52 mxc1 mxs1
Ce1 y 1 0.25 -0.52 mxc1 -mxs1
Ce1 z 1 -0.65 0 mzc1 0



