The material described by NdYbSe3 crystallizes in the orthorhombic Cmcm space group. Yb(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form a mixture of edge and corner-sharing YbSe6 octahedra. The corner-sharing octahedral tilt angles are 69°. Nd(1) is bonded in a 8-coordinate geometry to two equivalent Se(1) and six equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(1) and two equivalent Nd(1) atoms to form SeYb2Nd2 tetrahedra that share corners with eight equivalent Se(2)Yb2Nd3 square pyramids, corners with four equivalent Se(1)Yb2Nd2 tetrahedra, and edges with six equivalent Se(2)Yb2Nd3 square pyramids. In the second Se site, Se(2) is bonded to two equivalent Yb(1) and three equivalent Nd(1) atoms to form distorted SeYb2Nd3 square pyramids that share corners with nine equivalent Se(2)Yb2Nd3 square pyramids, corners with four equivalent Se(1)Yb2Nd2 tetrahedra, edges with six equivalent Se(2)Yb2Nd3 square pyramids, and edges with three equivalent Se(1)Yb2Nd2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_YbNdSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.533
_cell_length_b   7.533
_cell_length_c   9.287
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.281
_symmetry_Int_Tables_number   1
_cell_volume   277.107
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Yb  Yb0  1  0.000  0.000  0.000  1.0
  Yb  Yb1  1  0.000  0.000  0.500  1.0
  Nd  Nd2  1  0.249  0.751  0.750  1.0
  Nd  Nd3  1  0.751  0.249  0.250  1.0
  Se  Se4  1  0.110  0.890  0.250  1.0
  Se  Se5  1  0.890  0.110  0.750  1.0
  Se  Se6  1  0.641  0.359  0.575  1.0
  Se  Se7  1  0.359  0.641  0.425  1.0
  Se  Se8  1  0.641  0.359  0.925  1.0
  Se  Se9  1  0.359  0.641  0.075  1.0
[/CIF]
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The material described by NdYbSe3 crystallizes in the orthorhombic Cmcm space group. Yb(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form a mixture of edge and corner-sharing YbSe6 octahedra. The corner-sharing octahedral tilt angles are 69°. Nd(1) is bonded in a 8-coordinate geometry to two equivalent Se(1) and six equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(1) and two equivalent Nd(1) atoms to form SeYb2Nd2 tetrahedra that share corners with eight equivalent Se(2)Yb2Nd3 square pyramids, corners with four equivalent Se(1)Yb2Nd2 tetrahedra, and edges with six equivalent Se(2)Yb2Nd3 square pyramids. In the second Se site, Se(2) is bonded to two equivalent Yb(1) and three equivalent Nd(1) atoms to form distorted SeYb2Nd3 square pyramids that share corners with nine equivalent Se(2)Yb2Nd3 square pyramids, corners with four equivalent Se(1)Yb2Nd2 tetrahedra, edges with six equivalent Se(2)Yb2Nd3 square pyramids, and edges with three equivalent Se(1)Yb2Nd2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_YbNdSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.533
_cell_length_b   7.533
_cell_length_c   9.287
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.281
_symmetry_Int_Tables_number   1
_cell_volume   277.107
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Yb  Yb0  1  0.000  0.000  0.000  1.0
  Yb  Yb1  1  0.000  0.000  0.500  1.0
  Nd  Nd2  1  0.249  0.751  0.750  1.0
  Nd  Nd3  1  0.751  0.249  0.250  1.0
  Se  Se4  1  0.110  0.890  0.250  1.0
  Se  Se5  1  0.890  0.110  0.750  1.0
  Se  Se6  1  0.641  0.359  0.575  1.0
  Se  Se7  1  0.359  0.641  0.425  1.0
  Se  Se8  1  0.641  0.359  0.925  1.0
  Se  Se9  1  0.359  0.641  0.075  1.0
[/CIF]
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