The structure described by MgSnSi2O6 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded in a see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. Sn(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Sn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Sn(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgSi2SnO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.302
_cell_length_b   7.302
_cell_length_c   5.512
_cell_angle_alpha   75.526
_cell_angle_beta   75.526
_cell_angle_gamma   84.559
_symmetry_Int_Tables_number   1
_cell_volume   275.354
_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  0.724  0.276  0.250  1.0
  Mg  Mg1  1  0.276  0.724  0.750  1.0
  Si  Si2  1  0.815  0.627  0.780  1.0
  Si  Si3  1  0.373  0.185  0.720  1.0
  Si  Si4  1  0.627  0.815  0.280  1.0
  Si  Si5  1  0.185  0.373  0.220  1.0
  Sn  Sn6  1  0.862  0.138  0.750  1.0
  Sn  Sn7  1  0.138  0.862  0.250  1.0
  O  O8  1  0.703  0.710  0.545  1.0
  O  O9  1  0.290  0.297  0.955  1.0
  O  O10  1  0.297  0.290  0.455  1.0
  O  O11  1  0.710  0.703  0.045  1.0
  O  O12  1  0.790  0.398  0.881  1.0
  O  O13  1  0.602  0.210  0.619  1.0
  O  O14  1  0.210  0.602  0.119  1.0
  O  O15  1  0.398  0.790  0.381  1.0
  O  O16  1  0.686  0.034  0.173  1.0
  O  O17  1  0.966  0.314  0.327  1.0
  O  O18  1  0.034  0.686  0.673  1.0
  O  O19  1  0.314  0.966  0.827  1.0
[/CIF]
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The structure described by MgSnSi2O6 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded in a see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. Sn(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Sn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Sn(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgSi2SnO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.302
_cell_length_b   7.302
_cell_length_c   5.512
_cell_angle_alpha   75.526
_cell_angle_beta   75.526
_cell_angle_gamma   84.559
_symmetry_Int_Tables_number   1
_cell_volume   275.354
_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  0.724  0.276  0.250  1.0
  Mg  Mg1  1  0.276  0.724  0.750  1.0
  Si  Si2  1  0.815  0.627  0.780  1.0
  Si  Si3  1  0.373  0.185  0.720  1.0
  Si  Si4  1  0.627  0.815  0.280  1.0
  Si  Si5  1  0.185  0.373  0.220  1.0
  Sn  Sn6  1  0.862  0.138  0.750  1.0
  Sn  Sn7  1  0.138  0.862  0.250  1.0
  O  O8  1  0.703  0.710  0.545  1.0
  O  O9  1  0.290  0.297  0.955  1.0
  O  O10  1  0.297  0.290  0.455  1.0
  O  O11  1  0.710  0.703  0.045  1.0
  O  O12  1  0.790  0.398  0.881  1.0
  O  O13  1  0.602  0.210  0.619  1.0
  O  O14  1  0.210  0.602  0.119  1.0
  O  O15  1  0.398  0.790  0.381  1.0
  O  O16  1  0.686  0.034  0.173  1.0
  O  O17  1  0.966  0.314  0.327  1.0
  O  O18  1  0.034  0.686  0.673  1.0
  O  O19  1  0.314  0.966  0.827  1.0
[/CIF]
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