The material described by Mg2W9O13 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(3), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form distorted MgO6 octahedra that share corners with two equivalent W(5)O6 octahedra, corners with two equivalent W(2)O5 square pyramids, edges with two equivalent Mg(1)O6 octahedra, edges with three equivalent W(5)O6 octahedra, and edges with two equivalent W(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 14-15°. There are five inequivalent W sites. In the first W site, W(1) is bonded in a linear geometry to two equivalent O(7) atoms. In the second W site, W(2) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted WO5 square pyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent W(2)O5 square pyramids, and edges with three equivalent W(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 56-57°. In the third W site, W(3) is bonded to one O(5), two equivalent O(6), and two equivalent O(7) atoms to form WO5 square pyramids that share corners with two equivalent W(5)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with three equivalent W(5)O6 octahedra, and edges with two equivalent W(3)O5 square pyramids. The corner-sharing octahedral tilt angles are 13°. In the fourth W site, W(4) is bonded in a 6-coordinate geometry to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms. In the fifth W site, W(5) is bonded to one O(2), one O(7), two equivalent O(5), and two equivalent O(6) atoms to form WO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent W(3)O5 square pyramids, edges with two equivalent W(5)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, and edges with three equivalent W(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 14-15°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent W(4) and four equivalent W(2) atoms to form OW6 octahedra that share corners with two equivalent O(2)Mg2W2 tetrahedra, corners with eight equivalent O(3)MgW4 trigonal bipyramids, edges with two equivalent O(1)W6 octahedra, and edges with two equivalent O(3)MgW4 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Mg(1), one W(4), and one W(5) atom to form OMg2W2 tetrahedra that share  a cornercorner with one O(1)W6 octahedra, corners with four equivalent O(5)Mg2W3 square pyramids,  a cornercorner with one O(7)W4 tetrahedra, corners with two equivalent O(2)Mg2W2 tetrahedra,  an edgeedge with one O(5)Mg2W3 square pyramid, edges with two equivalent O(6)MgW4 square pyramids, and edges with two equivalent O(3)MgW4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°. In the third O site, O(3) is bonded to one Mg(1), two equivalent W(2), and two equivalent W(4) atoms to form distorted OMgW4 trigonal bipyramids that share corners with four equivalent O(1)W6 octahedra,  a cornercorner with one O(6)MgW4 square pyramid, corners with two equivalent O(5)Mg2W3 square pyramids,  an edgeedge with one O(1)W6 octahedra, edges with two equivalent O(2)Mg2W2 tetrahedra, and edges with two equivalent O(3)MgW4 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 16-67°. In the fourth O site, O(4) is bonded in a trigonal non-coplanar geometry to one W(2) and two equivalent W(4) atoms. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one W(3), and two equivalent W(5) atoms to form OMg2W3 square pyramids that share corners with two equivalent O(6)MgW4 square pyramids, corners with four equivalent O(2)Mg2W2 tetrahedra, corners with two equivalent O(3)MgW4 trigonal bipyramids, edges with two equivalent O(5)Mg2W3 square pyramids, edges with three equivalent O(6)MgW4 square pyramids,  an edgeedge with one O(2)Mg2W2 tetrahedra, and edges with two equivalent O(7)W4 tetrahedra. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent W(3), and two equivalent W(5) atoms to form OMgW4 square pyramids that share corners with two equivalent O(5)Mg2W3 square pyramids, corners with four equivalent O(7)W4 tetrahedra,  a cornercorner with one O(3)MgW4 trigonal bipyramid, edges with two equivalent O(6)MgW4 square pyramids, edges with three equivalent O(5)Mg2W3 square pyramids,  an edgeedge with one O(7)W4 tetrahedra, and edges with two equivalent O(2)Mg2W2 tetrahedra. In the seventh O site, O(7) is bonded to one W(1), one W(5), and two equivalent W(3) atoms to form OW4 tetrahedra that share corners with four equivalent O(6)MgW4 square pyramids,  a cornercorner with one O(2)Mg2W2 tetrahedra, corners with three equivalent O(7)W4 tetrahedra,  an edgeedge with one O(6)MgW4 square pyramid, and edges with two equivalent O(5)Mg2W3 square pyramids. is represented by the CIF card [CIF]
data_Mg2W9O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.223
_cell_length_b   5.527
_cell_length_c   19.148
_cell_angle_alpha   96.349
_cell_angle_beta   88.321
_cell_angle_gamma   106.258
_symmetry_Int_Tables_number   1
_cell_volume   325.407
_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  0.185  0.476  0.236  1.0
  Mg  Mg1  1  0.815  0.524  0.764  1.0
  W  W2  1  0.000  0.000  0.500  1.0
  W  W3  1  0.618  0.280  0.050  1.0
  W  W4  1  0.382  0.720  0.950  1.0
  W  W5  1  0.643  0.481  0.395  1.0
  W  W6  1  0.357  0.519  0.605  1.0
  W  W7  1  0.847  0.765  0.116  1.0
  W  W8  1  0.153  0.235  0.884  1.0
  W  W9  1  0.903  0.971  0.313  1.0
  W  W10  1  0.097  0.029  0.687  1.0
  O  O11  1  0.000  0.000  0.000  1.0
  O  O12  1  0.792  0.699  0.222  1.0
  O  O13  1  0.208  0.301  0.778  1.0
  O  O14  1  0.196  0.464  0.118  1.0
  O  O15  1  0.804  0.536  0.882  1.0
  O  O16  1  0.466  0.012  0.123  1.0
  O  O17  1  0.534  0.988  0.877  1.0
  O  O18  1  0.533  0.236  0.290  1.0
  O  O19  1  0.467  0.764  0.710  1.0
  O  O20  1  0.264  0.700  0.341  1.0
  O  O21  1  0.736  0.300  0.659  1.0
  O  O22  1  0.018  0.224  0.411  1.0
  O  O23  1  0.982  0.776  0.589  1.0
[/CIF]
.
The material described by Mg2W9O13 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(3), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form distorted MgO6 octahedra that share corners with two equivalent W(5)O6 octahedra, corners with two equivalent W(2)O5 square pyramids, edges with two equivalent Mg(1)O6 octahedra, edges with three equivalent W(5)O6 octahedra, and edges with two equivalent W(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 14-15°. There are five inequivalent W sites. In the first W site, W(1) is bonded in a linear geometry to two equivalent O(7) atoms. In the second W site, W(2) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted WO5 square pyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent W(2)O5 square pyramids, and edges with three equivalent W(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 56-57°. In the third W site, W(3) is bonded to one O(5), two equivalent O(6), and two equivalent O(7) atoms to form WO5 square pyramids that share corners with two equivalent W(5)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with three equivalent W(5)O6 octahedra, and edges with two equivalent W(3)O5 square pyramids. The corner-sharing octahedral tilt angles are 13°. In the fourth W site, W(4) is bonded in a 6-coordinate geometry to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms. In the fifth W site, W(5) is bonded to one O(2), one O(7), two equivalent O(5), and two equivalent O(6) atoms to form WO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent W(3)O5 square pyramids, edges with two equivalent W(5)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, and edges with three equivalent W(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 14-15°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent W(4) and four equivalent W(2) atoms to form OW6 octahedra that share corners with two equivalent O(2)Mg2W2 tetrahedra, corners with eight equivalent O(3)MgW4 trigonal bipyramids, edges with two equivalent O(1)W6 octahedra, and edges with two equivalent O(3)MgW4 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Mg(1), one W(4), and one W(5) atom to form OMg2W2 tetrahedra that share  a cornercorner with one O(1)W6 octahedra, corners with four equivalent O(5)Mg2W3 square pyramids,  a cornercorner with one O(7)W4 tetrahedra, corners with two equivalent O(2)Mg2W2 tetrahedra,  an edgeedge with one O(5)Mg2W3 square pyramid, edges with two equivalent O(6)MgW4 square pyramids, and edges with two equivalent O(3)MgW4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°. In the third O site, O(3) is bonded to one Mg(1), two equivalent W(2), and two equivalent W(4) atoms to form distorted OMgW4 trigonal bipyramids that share corners with four equivalent O(1)W6 octahedra,  a cornercorner with one O(6)MgW4 square pyramid, corners with two equivalent O(5)Mg2W3 square pyramids,  an edgeedge with one O(1)W6 octahedra, edges with two equivalent O(2)Mg2W2 tetrahedra, and edges with two equivalent O(3)MgW4 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 16-67°. In the fourth O site, O(4) is bonded in a trigonal non-coplanar geometry to one W(2) and two equivalent W(4) atoms. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one W(3), and two equivalent W(5) atoms to form OMg2W3 square pyramids that share corners with two equivalent O(6)MgW4 square pyramids, corners with four equivalent O(2)Mg2W2 tetrahedra, corners with two equivalent O(3)MgW4 trigonal bipyramids, edges with two equivalent O(5)Mg2W3 square pyramids, edges with three equivalent O(6)MgW4 square pyramids,  an edgeedge with one O(2)Mg2W2 tetrahedra, and edges with two equivalent O(7)W4 tetrahedra. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent W(3), and two equivalent W(5) atoms to form OMgW4 square pyramids that share corners with two equivalent O(5)Mg2W3 square pyramids, corners with four equivalent O(7)W4 tetrahedra,  a cornercorner with one O(3)MgW4 trigonal bipyramid, edges with two equivalent O(6)MgW4 square pyramids, edges with three equivalent O(5)Mg2W3 square pyramids,  an edgeedge with one O(7)W4 tetrahedra, and edges with two equivalent O(2)Mg2W2 tetrahedra. In the seventh O site, O(7) is bonded to one W(1), one W(5), and two equivalent W(3) atoms to form OW4 tetrahedra that share corners with four equivalent O(6)MgW4 square pyramids,  a cornercorner with one O(2)Mg2W2 tetrahedra, corners with three equivalent O(7)W4 tetrahedra,  an edgeedge with one O(6)MgW4 square pyramid, and edges with two equivalent O(5)Mg2W3 square pyramids. is represented by the CIF card [CIF]
data_Mg2W9O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.223
_cell_length_b   5.527
_cell_length_c   19.148
_cell_angle_alpha   96.349
_cell_angle_beta   88.321
_cell_angle_gamma   106.258
_symmetry_Int_Tables_number   1
_cell_volume   325.407
_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  0.185  0.476  0.236  1.0
  Mg  Mg1  1  0.815  0.524  0.764  1.0
  W  W2  1  0.000  0.000  0.500  1.0
  W  W3  1  0.618  0.280  0.050  1.0
  W  W4  1  0.382  0.720  0.950  1.0
  W  W5  1  0.643  0.481  0.395  1.0
  W  W6  1  0.357  0.519  0.605  1.0
  W  W7  1  0.847  0.765  0.116  1.0
  W  W8  1  0.153  0.235  0.884  1.0
  W  W9  1  0.903  0.971  0.313  1.0
  W  W10  1  0.097  0.029  0.687  1.0
  O  O11  1  0.000  0.000  0.000  1.0
  O  O12  1  0.792  0.699  0.222  1.0
  O  O13  1  0.208  0.301  0.778  1.0
  O  O14  1  0.196  0.464  0.118  1.0
  O  O15  1  0.804  0.536  0.882  1.0
  O  O16  1  0.466  0.012  0.123  1.0
  O  O17  1  0.534  0.988  0.877  1.0
  O  O18  1  0.533  0.236  0.290  1.0
  O  O19  1  0.467  0.764  0.710  1.0
  O  O20  1  0.264  0.700  0.341  1.0
  O  O21  1  0.736  0.300  0.659  1.0
  O  O22  1  0.018  0.224  0.411  1.0
  O  O23  1  0.982  0.776  0.589  1.0
[/CIF]
.