The crystal structure 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(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted MgO6 pentagonal pyramids that share corners with two equivalent Mg(2)O4 trigonal pyramids, corners with four equivalent Si(1)O4 trigonal pyramids,  an edgeedge with one Mg(2)O4 trigonal pyramid, and edges with two equivalent Si(1)O4 trigonal pyramids. In the second Mg site, Mg(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form MgO4 trigonal pyramids that share corners with two equivalent Mg(1)O6 pentagonal pyramids, corners with four equivalent Si(1)O4 trigonal pyramids, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted SiO4 trigonal pyramids that share corners with two equivalent Mg(1)O6 pentagonal pyramids, corners with two equivalent Mg(2)O4 trigonal pyramids, corners with two equivalent Si(1)O4 trigonal pyramids, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(1), one Mg(2), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Mg(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_MgSiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.041
_cell_length_b   7.765
_cell_length_c   7.765
_cell_angle_alpha   46.241
_cell_angle_beta   49.593
_cell_angle_gamma   49.593
_symmetry_Int_Tables_number   1
_cell_volume   217.493
_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  0.750  0.770  0.230  1.0
  Mg  Mg1  1  0.750  0.251  0.749  1.0
  Mg  Mg2  1  0.250  0.230  0.770  1.0
  Mg  Mg3  1  0.250  0.749  0.251  1.0
  Si  Si4  1  0.692  0.790  0.685  1.0
  Si  Si5  1  0.808  0.315  0.210  1.0
  Si  Si6  1  0.192  0.685  0.790  1.0
  Si  Si7  1  0.308  0.210  0.315  1.0
  O  O8  1  0.641  0.116  0.506  1.0
  O  O9  1  0.373  0.444  0.734  1.0
  O  O10  1  0.873  0.734  0.444  1.0
  O  O11  1  0.127  0.266  0.556  1.0
  O  O12  1  0.387  0.832  0.895  1.0
  O  O13  1  0.613  0.168  0.105  1.0
  O  O14  1  0.359  0.884  0.494  1.0
  O  O15  1  0.887  0.895  0.832  1.0
  O  O16  1  0.113  0.105  0.168  1.0
  O  O17  1  0.627  0.556  0.266  1.0
  O  O18  1  0.141  0.506  0.116  1.0
  O  O19  1  0.859  0.494  0.884  1.0
[/CIF]
.
The crystal structure 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(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted MgO6 pentagonal pyramids that share corners with two equivalent Mg(2)O4 trigonal pyramids, corners with four equivalent Si(1)O4 trigonal pyramids,  an edgeedge with one Mg(2)O4 trigonal pyramid, and edges with two equivalent Si(1)O4 trigonal pyramids. In the second Mg site, Mg(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form MgO4 trigonal pyramids that share corners with two equivalent Mg(1)O6 pentagonal pyramids, corners with four equivalent Si(1)O4 trigonal pyramids, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted SiO4 trigonal pyramids that share corners with two equivalent Mg(1)O6 pentagonal pyramids, corners with two equivalent Mg(2)O4 trigonal pyramids, corners with two equivalent Si(1)O4 trigonal pyramids, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(1), one Mg(2), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Mg(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_MgSiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.041
_cell_length_b   7.765
_cell_length_c   7.765
_cell_angle_alpha   46.241
_cell_angle_beta   49.593
_cell_angle_gamma   49.593
_symmetry_Int_Tables_number   1
_cell_volume   217.493
_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  0.750  0.770  0.230  1.0
  Mg  Mg1  1  0.750  0.251  0.749  1.0
  Mg  Mg2  1  0.250  0.230  0.770  1.0
  Mg  Mg3  1  0.250  0.749  0.251  1.0
  Si  Si4  1  0.692  0.790  0.685  1.0
  Si  Si5  1  0.808  0.315  0.210  1.0
  Si  Si6  1  0.192  0.685  0.790  1.0
  Si  Si7  1  0.308  0.210  0.315  1.0
  O  O8  1  0.641  0.116  0.506  1.0
  O  O9  1  0.373  0.444  0.734  1.0
  O  O10  1  0.873  0.734  0.444  1.0
  O  O11  1  0.127  0.266  0.556  1.0
  O  O12  1  0.387  0.832  0.895  1.0
  O  O13  1  0.613  0.168  0.105  1.0
  O  O14  1  0.359  0.884  0.494  1.0
  O  O15  1  0.887  0.895  0.832  1.0
  O  O16  1  0.113  0.105  0.168  1.0
  O  O17  1  0.627  0.556  0.266  1.0
  O  O18  1  0.141  0.506  0.116  1.0
  O  O19  1  0.859  0.494  0.884  1.0
[/CIF]
.