The compound described by MgNiSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form NiO6 octahedra that share corners with two equivalent Ni(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form NiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Ni(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Mg(2), one Ni(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Ni(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Ni(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(2), one Ni(1), and one Ni(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(1), one Ni(1), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgSiNiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.291
_cell_length_b   6.853
_cell_length_c   8.466
_cell_angle_alpha   90.771
_cell_angle_beta   143.505
_cell_angle_gamma   74.486
_symmetry_Int_Tables_number   1
_cell_volume   164.679
_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  0.486  0.250  0.161  1.0
  Mg  Mg1  1  0.497  0.743  0.831  1.0
  Si  Si2  1  0.497  0.243  0.822  1.0
  Si  Si3  1  0.494  0.743  0.173  1.0
  Ni  Ni4  1  0.495  0.492  0.497  1.0
  Ni  Ni5  1  0.495  0.992  0.497  1.0
  O  O6  1  0.238  0.124  0.585  1.0
  O  O7  1  0.741  0.367  0.841  1.0
  O  O8  1  0.754  0.860  0.411  1.0
  O  O9  1  0.252  0.616  0.153  1.0
  O  O10  1  0.856  0.577  0.220  1.0
  O  O11  1  0.128  0.917  0.863  1.0
  O  O12  1  0.133  0.409  0.773  1.0
  O  O13  1  0.862  0.069  0.132  1.0
  O  O14  1  0.500  0.743  0.589  1.0
  O  O15  1  0.490  0.242  0.405  1.0
[/CIF]
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The compound described by MgNiSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form NiO6 octahedra that share corners with two equivalent Ni(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form NiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Ni(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Ni(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Mg(2), one Ni(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Ni(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Ni(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(2), one Ni(1), and one Ni(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(1), one Ni(1), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgSiNiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.291
_cell_length_b   6.853
_cell_length_c   8.466
_cell_angle_alpha   90.771
_cell_angle_beta   143.505
_cell_angle_gamma   74.486
_symmetry_Int_Tables_number   1
_cell_volume   164.679
_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  0.486  0.250  0.161  1.0
  Mg  Mg1  1  0.497  0.743  0.831  1.0
  Si  Si2  1  0.497  0.243  0.822  1.0
  Si  Si3  1  0.494  0.743  0.173  1.0
  Ni  Ni4  1  0.495  0.492  0.497  1.0
  Ni  Ni5  1  0.495  0.992  0.497  1.0
  O  O6  1  0.238  0.124  0.585  1.0
  O  O7  1  0.741  0.367  0.841  1.0
  O  O8  1  0.754  0.860  0.411  1.0
  O  O9  1  0.252  0.616  0.153  1.0
  O  O10  1  0.856  0.577  0.220  1.0
  O  O11  1  0.128  0.917  0.863  1.0
  O  O12  1  0.133  0.409  0.773  1.0
  O  O13  1  0.862  0.069  0.132  1.0
  O  O14  1  0.500  0.743  0.589  1.0
  O  O15  1  0.490  0.242  0.405  1.0
[/CIF]
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