The material structure described by MgNdSe3 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 Nd(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Nd(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 37-58°. Nd(1) is bonded to six equivalent Se(1) atoms to form distorted NdSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Nd(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 37-58°. Se(1) is bonded in a distorted see-saw-like geometry to two equivalent Mg(1) and two equivalent Nd(1) atoms. is represented by the CIF file [CIF]
data_NdMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.036
_cell_length_b   7.036
_cell_length_c   7.707
_cell_angle_alpha   62.841
_cell_angle_beta   62.841
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   280.803
_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  0.162  0.162  0.513  1.0
  Mg  Mg1  1  0.838  0.838  0.487  1.0
  Nd  Nd2  1  0.352  0.352  0.943  1.0
  Nd  Nd3  1  0.648  0.648  0.057  1.0
  Se  Se4  1  0.209  0.962  0.252  1.0
  Se  Se5  1  0.791  0.038  0.748  1.0
  Se  Se6  1  0.962  0.577  0.252  1.0
  Se  Se7  1  0.038  0.423  0.748  1.0
  Se  Se8  1  0.577  0.209  0.252  1.0
  Se  Se9  1  0.423  0.791  0.748  1.0
[/CIF]
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The material structure described by MgNdSe3 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 Nd(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Nd(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 37-58°. Nd(1) is bonded to six equivalent Se(1) atoms to form distorted NdSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Nd(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 37-58°. Se(1) is bonded in a distorted see-saw-like geometry to two equivalent Mg(1) and two equivalent Nd(1) atoms. is represented by the CIF file [CIF]
data_NdMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.036
_cell_length_b   7.036
_cell_length_c   7.707
_cell_angle_alpha   62.841
_cell_angle_beta   62.841
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   280.803
_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  0.162  0.162  0.513  1.0
  Mg  Mg1  1  0.838  0.838  0.487  1.0
  Nd  Nd2  1  0.352  0.352  0.943  1.0
  Nd  Nd3  1  0.648  0.648  0.057  1.0
  Se  Se4  1  0.209  0.962  0.252  1.0
  Se  Se5  1  0.791  0.038  0.748  1.0
  Se  Se6  1  0.962  0.577  0.252  1.0
  Se  Se7  1  0.038  0.423  0.748  1.0
  Se  Se8  1  0.577  0.209  0.252  1.0
  Se  Se9  1  0.423  0.791  0.748  1.0
[/CIF]
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