The crystal structure described by MgPrSe3 is Ilmenite structured and crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent Se(1) atoms to form MgSe6 octahedra that share corners with nine equivalent Pr(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Pr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-58°. Pr(1) is bonded to six equivalent Se(1) atoms to form distorted PrSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Pr(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-58°. Se(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Pr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_PrMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.100
_cell_length_b   7.100
_cell_length_c   7.723
_cell_angle_alpha   62.634
_cell_angle_beta   62.634
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   285.778
_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
  Mg  Mg0  1  0.161  0.161  0.518  1.0
  Mg  Mg1  1  0.839  0.839  0.482  1.0
  Pr  Pr2  1  0.352  0.352  0.945  1.0
  Pr  Pr3  1  0.648  0.648  0.055  1.0
  Se  Se4  1  0.214  0.956  0.258  1.0
  Se  Se5  1  0.786  0.044  0.742  1.0
  Se  Se6  1  0.956  0.572  0.258  1.0
  Se  Se7  1  0.044  0.428  0.742  1.0
  Se  Se8  1  0.572  0.214  0.258  1.0
  Se  Se9  1  0.428  0.786  0.742  1.0
[/CIF]
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The crystal structure described by MgPrSe3 is Ilmenite structured and crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent Se(1) atoms to form MgSe6 octahedra that share corners with nine equivalent Pr(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Pr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-58°. Pr(1) is bonded to six equivalent Se(1) atoms to form distorted PrSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Pr(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-58°. Se(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Pr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_PrMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.100
_cell_length_b   7.100
_cell_length_c   7.723
_cell_angle_alpha   62.634
_cell_angle_beta   62.634
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   285.778
_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
  Mg  Mg0  1  0.161  0.161  0.518  1.0
  Mg  Mg1  1  0.839  0.839  0.482  1.0
  Pr  Pr2  1  0.352  0.352  0.945  1.0
  Pr  Pr3  1  0.648  0.648  0.055  1.0
  Se  Se4  1  0.214  0.956  0.258  1.0
  Se  Se5  1  0.786  0.044  0.742  1.0
  Se  Se6  1  0.956  0.572  0.258  1.0
  Se  Se7  1  0.044  0.428  0.742  1.0
  Se  Se8  1  0.572  0.214  0.258  1.0
  Se  Se9  1  0.428  0.786  0.742  1.0
[/CIF]
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