The compound described by MgTi4(CoO5)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted MgO6 octahedra that share corners with two equivalent Ti(2)O5 trigonal bipyramids, corners with four equivalent Co(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Ti(2)O5 trigonal bipyramids. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(5), two equivalent O(3), and three equivalent O(4) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O5 trigonal bipyramid,  a cornercorner with one Co(1)O5 trigonal bipyramid, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Co(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 38°. In the second Ti site, Ti(2) is bonded to one O(1), one O(5), and three equivalent O(2) atoms to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Ti(1)O6 octahedra, corners with two equivalent Ti(2)O5 trigonal bipyramids, corners with three equivalent Co(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Ti(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 53-65°. Co(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(5) atoms to form distorted CoO5 trigonal bipyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(1)O5 trigonal bipyramids, corners with three equivalent Ti(2)O5 trigonal bipyramids, and edges with three equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-67°. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Ti(2), and one Co(1) atom to form distorted OMg2TiCo tetrahedra that share corners with three equivalent O(2)MgTi3 tetrahedra, corners with three equivalent O(5)Ti2Co2 tetrahedra, corners with four equivalent O(1)Mg2TiCo tetrahedra,  a cornercorner with one O(4)Ti3Co trigonal pyramid,  an edgeedge with one O(1)Mg2TiCo tetrahedra, and edges with two equivalent O(2)MgTi3 tetrahedra. In the second O site, O(2) is bonded to one Mg(1) and three equivalent Ti(2) atoms to form OMgTi3 tetrahedra that share corners with three equivalent O(1)Mg2TiCo tetrahedra, corners with three equivalent O(2)MgTi3 tetrahedra, corners with three equivalent O(5)Ti2Co2 tetrahedra, edges with two equivalent O(1)Mg2TiCo tetrahedra, and edges with two equivalent O(2)MgTi3 tetrahedra. In the third O site, O(3) is bonded in a distorted T-shaped geometry to two equivalent Ti(1) and one Co(1) atom. In the fourth O site, O(4) is bonded to three equivalent Ti(1) and one Co(1) atom to form distorted OTi3Co trigonal pyramids that share  a cornercorner with one O(1)Mg2TiCo tetrahedra,  a cornercorner with one O(5)Ti2Co2 tetrahedra, corners with two equivalent O(4)Ti3Co trigonal pyramids, edges with two equivalent O(5)Ti2Co2 tetrahedra, and edges with two equivalent O(4)Ti3Co trigonal pyramids. In the fifth O site, O(5) is bonded to one Ti(1), one Ti(2), and two equivalent Co(1) atoms to form distorted OTi2Co2 tetrahedra that share corners with two equivalent O(5)Ti2Co2 tetrahedra, corners with three equivalent O(1)Mg2TiCo tetrahedra, corners with three equivalent O(2)MgTi3 tetrahedra,  a cornercorner with one O(4)Ti3Co trigonal pyramid, and edges with two equivalent O(4)Ti3Co trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgTi4(CoO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.639
_cell_length_b   5.475
_cell_length_c   11.046
_cell_angle_alpha   97.093
_cell_angle_beta   90.000
_cell_angle_gamma   109.408
_symmetry_Int_Tables_number   1
_cell_volume   205.749
_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  0.000  0.000  1.0
  Ti  Ti1  1  0.135  0.271  0.549  1.0
  Ti  Ti2  1  0.179  0.358  0.888  1.0
  Ti  Ti3  1  0.821  0.642  0.112  1.0
  Ti  Ti4  1  0.865  0.729  0.451  1.0
  Co  Co5  1  0.155  0.310  0.265  1.0
  Co  Co6  1  0.845  0.690  0.735  1.0
  O  O7  1  0.000  0.001  0.124  1.0
  O  O8  1  0.321  0.641  0.038  1.0
  O  O9  1  0.029  0.058  0.394  1.0
  O  O10  1  0.304  0.608  0.440  1.0
  O  O11  1  0.248  0.496  0.742  1.0
  O  O12  1  0.752  0.504  0.258  1.0
  O  O13  1  0.696  0.392  0.560  1.0
  O  O14  1  1.000  0.999  0.876  1.0
  O  O15  1  0.679  0.359  0.962  1.0
  O  O16  1  0.971  0.942  0.606  1.0
[/CIF]
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The compound described by MgTi4(CoO5)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted MgO6 octahedra that share corners with two equivalent Ti(2)O5 trigonal bipyramids, corners with four equivalent Co(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Ti(2)O5 trigonal bipyramids. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(5), two equivalent O(3), and three equivalent O(4) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O5 trigonal bipyramid,  a cornercorner with one Co(1)O5 trigonal bipyramid, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Co(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 38°. In the second Ti site, Ti(2) is bonded to one O(1), one O(5), and three equivalent O(2) atoms to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Ti(1)O6 octahedra, corners with two equivalent Ti(2)O5 trigonal bipyramids, corners with three equivalent Co(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Ti(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 53-65°. Co(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(5) atoms to form distorted CoO5 trigonal bipyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(1)O5 trigonal bipyramids, corners with three equivalent Ti(2)O5 trigonal bipyramids, and edges with three equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-67°. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Ti(2), and one Co(1) atom to form distorted OMg2TiCo tetrahedra that share corners with three equivalent O(2)MgTi3 tetrahedra, corners with three equivalent O(5)Ti2Co2 tetrahedra, corners with four equivalent O(1)Mg2TiCo tetrahedra,  a cornercorner with one O(4)Ti3Co trigonal pyramid,  an edgeedge with one O(1)Mg2TiCo tetrahedra, and edges with two equivalent O(2)MgTi3 tetrahedra. In the second O site, O(2) is bonded to one Mg(1) and three equivalent Ti(2) atoms to form OMgTi3 tetrahedra that share corners with three equivalent O(1)Mg2TiCo tetrahedra, corners with three equivalent O(2)MgTi3 tetrahedra, corners with three equivalent O(5)Ti2Co2 tetrahedra, edges with two equivalent O(1)Mg2TiCo tetrahedra, and edges with two equivalent O(2)MgTi3 tetrahedra. In the third O site, O(3) is bonded in a distorted T-shaped geometry to two equivalent Ti(1) and one Co(1) atom. In the fourth O site, O(4) is bonded to three equivalent Ti(1) and one Co(1) atom to form distorted OTi3Co trigonal pyramids that share  a cornercorner with one O(1)Mg2TiCo tetrahedra,  a cornercorner with one O(5)Ti2Co2 tetrahedra, corners with two equivalent O(4)Ti3Co trigonal pyramids, edges with two equivalent O(5)Ti2Co2 tetrahedra, and edges with two equivalent O(4)Ti3Co trigonal pyramids. In the fifth O site, O(5) is bonded to one Ti(1), one Ti(2), and two equivalent Co(1) atoms to form distorted OTi2Co2 tetrahedra that share corners with two equivalent O(5)Ti2Co2 tetrahedra, corners with three equivalent O(1)Mg2TiCo tetrahedra, corners with three equivalent O(2)MgTi3 tetrahedra,  a cornercorner with one O(4)Ti3Co trigonal pyramid, and edges with two equivalent O(4)Ti3Co trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgTi4(CoO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.639
_cell_length_b   5.475
_cell_length_c   11.046
_cell_angle_alpha   97.093
_cell_angle_beta   90.000
_cell_angle_gamma   109.408
_symmetry_Int_Tables_number   1
_cell_volume   205.749
_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  0.000  0.000  1.0
  Ti  Ti1  1  0.135  0.271  0.549  1.0
  Ti  Ti2  1  0.179  0.358  0.888  1.0
  Ti  Ti3  1  0.821  0.642  0.112  1.0
  Ti  Ti4  1  0.865  0.729  0.451  1.0
  Co  Co5  1  0.155  0.310  0.265  1.0
  Co  Co6  1  0.845  0.690  0.735  1.0
  O  O7  1  0.000  0.001  0.124  1.0
  O  O8  1  0.321  0.641  0.038  1.0
  O  O9  1  0.029  0.058  0.394  1.0
  O  O10  1  0.304  0.608  0.440  1.0
  O  O11  1  0.248  0.496  0.742  1.0
  O  O12  1  0.752  0.504  0.258  1.0
  O  O13  1  0.696  0.392  0.560  1.0
  O  O14  1  1.000  0.999  0.876  1.0
  O  O15  1  0.679  0.359  0.962  1.0
  O  O16  1  0.971  0.942  0.606  1.0
[/CIF]
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