The material described by Mg(NiO2)4 is beta indium sulfide-derived structured and crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra and corners with six equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-62°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with four equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Ni(2) and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ni(1) and two equivalent Ni(2) atoms. In the third O site, O(3) is bonded to one Mg(1), one Ni(2), and two equivalent Ni(1) atoms to form a mixture of corner and edge-sharing OMgNi3 tetrahedra. In the fourth O site, O(4) is bonded to one Mg(1), one Ni(1), and two equivalent Ni(2) atoms to form a mixture of distorted corner and edge-sharing OMgNi3 trigonal pyramids. is represented by the CIF file [CIF]
data_Mg(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.810
_cell_length_b   5.704
_cell_length_c   5.810
_cell_angle_alpha   60.603
_cell_angle_beta   58.486
_cell_angle_gamma   60.603
_symmetry_Int_Tables_number   1
_cell_volume   135.734
_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
  Mg  Mg0  1  0.113  0.137  0.113  1.0
  Ni  Ni1  1  0.501  0.502  0.501  1.0
  Ni  Ni2  1  0.501  0.996  0.501  1.0
  Ni  Ni3  1  0.994  0.502  0.502  1.0
  Ni  Ni4  1  0.502  0.502  0.994  1.0
  O  O5  1  0.749  0.723  0.305  1.0
  O  O6  1  0.750  0.714  0.750  1.0
  O  O7  1  0.253  0.275  0.697  1.0
  O  O8  1  0.252  0.719  0.252  1.0
  O  O9  1  0.252  0.277  0.252  1.0
  O  O10  1  0.697  0.275  0.253  1.0
  O  O11  1  0.305  0.723  0.749  1.0
  O  O12  1  0.750  0.286  0.750  1.0
[/CIF]
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The material described by Mg(NiO2)4 is beta indium sulfide-derived structured and crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra and corners with six equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-62°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with four equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Ni(2) and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ni(1) and two equivalent Ni(2) atoms. In the third O site, O(3) is bonded to one Mg(1), one Ni(2), and two equivalent Ni(1) atoms to form a mixture of corner and edge-sharing OMgNi3 tetrahedra. In the fourth O site, O(4) is bonded to one Mg(1), one Ni(1), and two equivalent Ni(2) atoms to form a mixture of distorted corner and edge-sharing OMgNi3 trigonal pyramids. is represented by the CIF file [CIF]
data_Mg(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.810
_cell_length_b   5.704
_cell_length_c   5.810
_cell_angle_alpha   60.603
_cell_angle_beta   58.486
_cell_angle_gamma   60.603
_symmetry_Int_Tables_number   1
_cell_volume   135.734
_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
  Mg  Mg0  1  0.113  0.137  0.113  1.0
  Ni  Ni1  1  0.501  0.502  0.501  1.0
  Ni  Ni2  1  0.501  0.996  0.501  1.0
  Ni  Ni3  1  0.994  0.502  0.502  1.0
  Ni  Ni4  1  0.502  0.502  0.994  1.0
  O  O5  1  0.749  0.723  0.305  1.0
  O  O6  1  0.750  0.714  0.750  1.0
  O  O7  1  0.253  0.275  0.697  1.0
  O  O8  1  0.252  0.719  0.252  1.0
  O  O9  1  0.252  0.277  0.252  1.0
  O  O10  1  0.697  0.275  0.253  1.0
  O  O11  1  0.305  0.723  0.749  1.0
  O  O12  1  0.750  0.286  0.750  1.0
[/CIF]
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