The crystal structure described by MgTi2(SiO4)2 crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Ti(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 64-72°. Ti(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted TiO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Si(1)O4 tetrahedra, corners with three equivalent Si(2)O4 tetrahedra, and edges with two equivalent Ti(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with six equivalent Ti(1)O6 octahedra and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-55°. In the second Si site, Si(2) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with six equivalent Ti(1)O6 octahedra and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mg(1), one Ti(1), and one Si(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ti(1) and one Si(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ti(1) and one Si(1) atom. In the fourth O site, O(4) is bonded to one Mg(1), two equivalent Ti(1), and one Si(2) atom to form distorted edge-sharing OMgTi2Si tetrahedra. is represented by the CIF file [CIF]
data_MgTi2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.053
_cell_length_b   5.053
_cell_length_c   6.167
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   111.473
_symmetry_Int_Tables_number   1
_cell_volume   146.564
_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  0.665  0.335  0.250  1.0
  Ti  Ti1  1  0.009  0.991  0.536  1.0
  Ti  Ti2  1  0.009  0.991  0.964  1.0
  Si  Si3  1  0.652  0.348  0.750  1.0
  Si  Si4  1  0.345  0.655  0.250  1.0
  O  O5  1  0.766  0.234  0.534  1.0
  O  O6  1  0.228  0.772  0.461  1.0
  O  O7  1  0.766  0.234  0.966  1.0
  O  O8  1  0.228  0.772  0.039  1.0
  O  O9  1  0.770  0.699  0.750  1.0
  O  O10  1  0.701  0.759  0.250  1.0
  O  O11  1  0.241  0.299  0.250  1.0
  O  O12  1  0.301  0.230  0.750  1.0
[/CIF]
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The crystal structure described by MgTi2(SiO4)2 crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Ti(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 64-72°. Ti(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted TiO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Si(1)O4 tetrahedra, corners with three equivalent Si(2)O4 tetrahedra, and edges with two equivalent Ti(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with six equivalent Ti(1)O6 octahedra and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-55°. In the second Si site, Si(2) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with six equivalent Ti(1)O6 octahedra and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mg(1), one Ti(1), and one Si(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ti(1) and one Si(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ti(1) and one Si(1) atom. In the fourth O site, O(4) is bonded to one Mg(1), two equivalent Ti(1), and one Si(2) atom to form distorted edge-sharing OMgTi2Si tetrahedra. is represented by the CIF file [CIF]
data_MgTi2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.053
_cell_length_b   5.053
_cell_length_c   6.167
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   111.473
_symmetry_Int_Tables_number   1
_cell_volume   146.564
_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  0.665  0.335  0.250  1.0
  Ti  Ti1  1  0.009  0.991  0.536  1.0
  Ti  Ti2  1  0.009  0.991  0.964  1.0
  Si  Si3  1  0.652  0.348  0.750  1.0
  Si  Si4  1  0.345  0.655  0.250  1.0
  O  O5  1  0.766  0.234  0.534  1.0
  O  O6  1  0.228  0.772  0.461  1.0
  O  O7  1  0.766  0.234  0.966  1.0
  O  O8  1  0.228  0.772  0.039  1.0
  O  O9  1  0.770  0.699  0.750  1.0
  O  O10  1  0.701  0.759  0.250  1.0
  O  O11  1  0.241  0.299  0.250  1.0
  O  O12  1  0.301  0.230  0.750  1.0
[/CIF]
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