#\#CIF_2.0
# Created by the Bilbao Crystallographic Server
# http://www.cryst.ehu.es
# Date: 22/11/2020

data_5yOhtAoR
_audit_creation_date            2020-11-22
_audit_creation_method          "Bilbao Crystallographic Server"

_citation_journal_abbrev        "J. Phys.: Condens. Matter"
_citation_journal_volume        29
_citation_page_first            ?
_citation_page_last             ?
_citation_article_id            045802
_citation_year                  2017
_citation_DOI                   10.1088/1361-648X/29/4/045802

loop_
_citation_author_name
"C. Ritter"
"A. Provino"
"P. Manfrinetti"
"A.K. Pathak"



_atomic_positions_source_database_code_ICSD  257404
_atomic_positions_source_other               ?

_transition_temperature  36
_experiment_temperature  5

loop_
_irrep_id
_irrep_dimension
_irrep_small_dimension
_irrep_direction_type
_irrep_action
_irrep_modes_number
_irrep_presence
mM5-  2  2  general  primary  1  .
mM1-  1  1    .    primary  1  .


_exptl_crystal_magnetic_properties_details
;
NPD
Between 48K and 36K another magnetic phase is reported with the moments on the basal plane (see #1.376)
Strong magnetostructural effect with a magnetic induced strain
;

_active_magnetic_irreps_details
;
1k magnetic structure
Two irreps are active as primary, i.e. two order parameters are necessary in the sense of Landau theory.
The other magnetic structure at higher temperature with the moments on the ab plane is associated a single order parameter according to one of the two irreps: mM5- (see #1.376)
The magnetic ordering of this model only reduces the parent symmetry into a monoclinc MSG, as the mM5- ordering is along a special direction. The monoclinic axis is along the (-1,1,0) direction of the parent structure. The unit cell strain of the reported triclinic unit cell with respect to the tetragonal one complies within its tolerances with monoclinic symmetry.
The reduction from monoclinic into a a triclinic symmetry is only produced by small displacements on the xy plane of the Ce1 and Ge1 atoms, from their (0,0,z) parent positions.
This small atomic displacements, which break further the symmetry, cannot be considered an induced effect of the magnetic ordering. It is either an artefact of the model or an additional symmetry-breaking structural distortion, i.e. a additional independent order parameter.
An older version (30/04/2020) of this entry has been corrected.
;

_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'

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  '-c,b,a-b+3c;1/4,1/4,1/4'



_space_group_magn.number_BNS  2.7
_space_group_magn.name_BNS  "P_S -1"
_cell_length_a             4.3359(3)
_cell_length_b             4.3347(3)
_cell_length_c             15.9628(3)
_cell_angle_alpha          90.22(1)
_cell_angle_beta           90.26(4)
_cell_angle_gamma          89.992(2)

loop_
_space_group_symop_magn_operation.id
_space_group_symop_magn_operation.xyz
1 x,y,z,+1
2 -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
Ce1 Ce 0.989(2) 0.010(2) 0.3233(1) 1.
Sc1_1 Sc 0.00000 0.50000 0.00000 1
Sc1_2 Sc  0.50000 0.00000 0.00000 1
Ge1 Ge 0.007(1) 0.996(1) 0.1207(8) 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
Ce1 0.60(1) 0.60 1.15(4) mx,my,mz 1.42(4)

