The compound described by MgSiO3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with four equivalent Si(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Si(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SiO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with three equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(2), two equivalent Mg(1), and two equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing OMg3Si2 square pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(2) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a see-saw-like geometry to one Mg(1), one Mg(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_MgSiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.377
_cell_length_b   6.377
_cell_length_c   4.895
_cell_angle_alpha   84.046
_cell_angle_beta   84.046
_cell_angle_gamma   80.386
_symmetry_Int_Tables_number   1
_cell_volume   194.440
_cell_formula_units_Z   4
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  0.112  0.888  0.250  1.0
  Mg  Mg1  1  0.693  0.307  0.250  1.0
  Mg  Mg2  1  0.888  0.112  0.750  1.0
  Mg  Mg3  1  0.307  0.693  0.750  1.0
  Si  Si4  1  0.327  0.167  0.528  1.0
  Si  Si5  1  0.673  0.833  0.472  1.0
  Si  Si6  1  0.833  0.673  0.972  1.0
  Si  Si7  1  0.167  0.327  0.028  1.0
  O  O8  1  0.936  0.801  0.631  1.0
  O  O9  1  0.712  0.604  0.303  1.0
  O  O10  1  0.895  0.385  0.925  1.0
  O  O11  1  0.801  0.936  0.131  1.0
  O  O12  1  0.199  0.064  0.869  1.0
  O  O13  1  0.604  0.712  0.803  1.0
  O  O14  1  0.105  0.615  0.075  1.0
  O  O15  1  0.385  0.895  0.425  1.0
  O  O16  1  0.615  0.105  0.575  1.0
  O  O17  1  0.396  0.288  0.197  1.0
  O  O18  1  0.288  0.396  0.697  1.0
  O  O19  1  0.064  0.199  0.369  1.0
[/CIF]
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The compound described by MgSiO3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with four equivalent Si(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Si(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SiO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with three equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(2), two equivalent Mg(1), and two equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing OMg3Si2 square pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(2) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a see-saw-like geometry to one Mg(1), one Mg(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_MgSiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.377
_cell_length_b   6.377
_cell_length_c   4.895
_cell_angle_alpha   84.046
_cell_angle_beta   84.046
_cell_angle_gamma   80.386
_symmetry_Int_Tables_number   1
_cell_volume   194.440
_cell_formula_units_Z   4
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  0.112  0.888  0.250  1.0
  Mg  Mg1  1  0.693  0.307  0.250  1.0
  Mg  Mg2  1  0.888  0.112  0.750  1.0
  Mg  Mg3  1  0.307  0.693  0.750  1.0
  Si  Si4  1  0.327  0.167  0.528  1.0
  Si  Si5  1  0.673  0.833  0.472  1.0
  Si  Si6  1  0.833  0.673  0.972  1.0
  Si  Si7  1  0.167  0.327  0.028  1.0
  O  O8  1  0.936  0.801  0.631  1.0
  O  O9  1  0.712  0.604  0.303  1.0
  O  O10  1  0.895  0.385  0.925  1.0
  O  O11  1  0.801  0.936  0.131  1.0
  O  O12  1  0.199  0.064  0.869  1.0
  O  O13  1  0.604  0.712  0.803  1.0
  O  O14  1  0.105  0.615  0.075  1.0
  O  O15  1  0.385  0.895  0.425  1.0
  O  O16  1  0.615  0.105  0.575  1.0
  O  O17  1  0.396  0.288  0.197  1.0
  O  O18  1  0.288  0.396  0.697  1.0
  O  O19  1  0.064  0.199  0.369  1.0
[/CIF]
.