The compound described by MgTi2(SiO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(3) and four equivalent O(2) atoms. Ti(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form distorted TiO6 pentagonal pyramids that share corners with four equivalent Si(1)O4 tetrahedra, edges with two equivalent Ti(1)O6 pentagonal pyramids, and  an edgeedge with one Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with four equivalent Ti(1)O6 pentagonal pyramids and  an edgeedge with one Ti(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Ti(1) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Ti(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 Ti(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_MgTi2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.338
_cell_length_b   5.622
_cell_length_c   5.622
_cell_angle_alpha   110.031
_cell_angle_beta   94.764
_cell_angle_gamma   120.014
_symmetry_Int_Tables_number   1
_cell_volume   154.800
_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  0.500  0.500  0.500  1.0
  Ti  Ti1  1  0.871  0.135  0.236  1.0
  Ti  Ti2  1  0.129  0.865  0.764  1.0
  Si  Si3  1  0.685  0.378  0.807  1.0
  Si  Si4  1  0.315  0.622  0.193  1.0
  O  O5  1  0.748  0.252  0.996  1.0
  O  O6  1  0.205  0.614  0.455  1.0
  O  O7  1  0.205  0.251  0.091  1.0
  O  O8  1  0.373  0.204  0.668  1.0
  O  O9  1  0.252  0.748  0.004  1.0
  O  O10  1  0.795  0.386  0.545  1.0
  O  O11  1  0.795  0.749  0.909  1.0
  O  O12  1  0.627  0.796  0.332  1.0
[/CIF]
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The compound described by MgTi2(SiO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(3) and four equivalent O(2) atoms. Ti(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form distorted TiO6 pentagonal pyramids that share corners with four equivalent Si(1)O4 tetrahedra, edges with two equivalent Ti(1)O6 pentagonal pyramids, and  an edgeedge with one Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with four equivalent Ti(1)O6 pentagonal pyramids and  an edgeedge with one Ti(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Ti(1) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Ti(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 Ti(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_MgTi2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.338
_cell_length_b   5.622
_cell_length_c   5.622
_cell_angle_alpha   110.031
_cell_angle_beta   94.764
_cell_angle_gamma   120.014
_symmetry_Int_Tables_number   1
_cell_volume   154.800
_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  0.500  0.500  0.500  1.0
  Ti  Ti1  1  0.871  0.135  0.236  1.0
  Ti  Ti2  1  0.129  0.865  0.764  1.0
  Si  Si3  1  0.685  0.378  0.807  1.0
  Si  Si4  1  0.315  0.622  0.193  1.0
  O  O5  1  0.748  0.252  0.996  1.0
  O  O6  1  0.205  0.614  0.455  1.0
  O  O7  1  0.205  0.251  0.091  1.0
  O  O8  1  0.373  0.204  0.668  1.0
  O  O9  1  0.252  0.748  0.004  1.0
  O  O10  1  0.795  0.386  0.545  1.0
  O  O11  1  0.795  0.749  0.909  1.0
  O  O12  1  0.627  0.796  0.332  1.0
[/CIF]
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