The crystal structure described by Mn4NiSe5 crystallizes in the orthorhombic Immm space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the second Mn site, Mn(2) is bonded in a 4-coordinate geometry to two equivalent Se(1) and four equivalent Se(2) atoms. Ni(1) is bonded to two equivalent Se(3) and four equivalent Se(1) atoms to form a mixture of corner and edge-sharing NiSe6 octahedra. The corner-sharing octahedra are not tilted. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Mn(1), two equivalent Mn(2), and two equivalent Ni(1) atoms to form a mixture of corner and edge-sharing SeMn4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-36°. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to two equivalent Mn(1) and four equivalent Mn(2) atoms. In the third Se site, Se(3) is bonded to four equivalent Mn(1) and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing SeMn4Ni2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mn4NiSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.658
_cell_length_b   10.658
_cell_length_c   10.658
_cell_angle_alpha   160.995
_cell_angle_beta   154.433
_cell_angle_gamma   32.052
_symmetry_Int_Tables_number   1
_cell_volume   170.016
_cell_formula_units_Z   1
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
  Mn  Mn0  1  0.621  0.621  0.000  1.0
  Mn  Mn1  1  0.169  0.169  0.000  1.0
  Mn  Mn2  1  0.831  0.831  0.000  1.0
  Mn  Mn3  1  0.379  0.379  0.000  1.0
  Ni  Ni4  1  0.000  0.000  0.000  1.0
  Se  Se5  1  0.917  0.417  0.500  1.0
  Se  Se6  1  0.700  0.200  0.500  1.0
  Se  Se7  1  0.300  0.800  0.500  1.0
  Se  Se8  1  0.500  0.000  0.500  1.0
  Se  Se9  1  0.083  0.583  0.500  1.0
[/CIF]
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The crystal structure described by Mn4NiSe5 crystallizes in the orthorhombic Immm space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the second Mn site, Mn(2) is bonded in a 4-coordinate geometry to two equivalent Se(1) and four equivalent Se(2) atoms. Ni(1) is bonded to two equivalent Se(3) and four equivalent Se(1) atoms to form a mixture of corner and edge-sharing NiSe6 octahedra. The corner-sharing octahedra are not tilted. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Mn(1), two equivalent Mn(2), and two equivalent Ni(1) atoms to form a mixture of corner and edge-sharing SeMn4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-36°. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to two equivalent Mn(1) and four equivalent Mn(2) atoms. In the third Se site, Se(3) is bonded to four equivalent Mn(1) and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing SeMn4Ni2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mn4NiSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.658
_cell_length_b   10.658
_cell_length_c   10.658
_cell_angle_alpha   160.995
_cell_angle_beta   154.433
_cell_angle_gamma   32.052
_symmetry_Int_Tables_number   1
_cell_volume   170.016
_cell_formula_units_Z   1
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
  Mn  Mn0  1  0.621  0.621  0.000  1.0
  Mn  Mn1  1  0.169  0.169  0.000  1.0
  Mn  Mn2  1  0.831  0.831  0.000  1.0
  Mn  Mn3  1  0.379  0.379  0.000  1.0
  Ni  Ni4  1  0.000  0.000  0.000  1.0
  Se  Se5  1  0.917  0.417  0.500  1.0
  Se  Se6  1  0.700  0.200  0.500  1.0
  Se  Se7  1  0.300  0.800  0.500  1.0
  Se  Se8  1  0.500  0.000  0.500  1.0
  Se  Se9  1  0.083  0.583  0.500  1.0
[/CIF]
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