The compound described by MgTm4Ti2O10 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a distorted T-shaped geometry to one O(4) and two equivalent O(1) atoms. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(1), one O(3), one O(5), one O(6), and two equivalent O(2) atoms to form distorted TmO6 pentagonal pyramids that share  a cornercorner with one Ti(2)O6 octahedra, corners with three equivalent Tm(1)O6 pentagonal pyramids, edges with two equivalent Ti(2)O6 octahedra, and  an edgeedge with one Ti(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 31°. In the second Tm site, Tm(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(6), and two equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted TiO6 pentagonal pyramids that share corners with two equivalent Ti(1)O6 pentagonal pyramids and edges with two equivalent Tm(1)O6 pentagonal pyramids. In the second Ti site, Ti(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Tm(1)O6 pentagonal pyramids, and edges with four equivalent Tm(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 32°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Tm(1), one Tm(2), and one Ti(1) atom. In the second O site, O(2) is bonded to one Tm(2), two equivalent Tm(1), and one Ti(2) atom to form OTm3Ti trigonal pyramids that share  a cornercorner with one O(4)Tm2MgTi2 trigonal bipyramid, corners with three equivalent O(2)Tm3Ti trigonal pyramids, edges with two equivalent O(3)Tm2Ti2 tetrahedra, and edges with two equivalent O(5)Tm3Ti tetrahedra. In the third O site, O(3) is bonded to two equivalent Tm(1) and two equivalent Ti(2) atoms to form distorted OTm2Ti2 tetrahedra that share corners with two equivalent O(3)Tm2Ti2 tetrahedra, corners with two equivalent O(5)Tm3Ti tetrahedra, and edges with four equivalent O(2)Tm3Ti trigonal pyramids. In the fourth O site, O(4) is bonded to one Mg(1), two equivalent Tm(2), and two equivalent Ti(1) atoms to form OTm2MgTi2 trigonal bipyramids that share corners with two equivalent O(4)Tm2MgTi2 trigonal bipyramids, corners with two equivalent O(2)Tm3Ti trigonal pyramids, and edges with four equivalent O(5)Tm3Ti tetrahedra. In the fifth O site, O(5) is bonded to one Tm(1), two equivalent Tm(2), and one Ti(1) atom to form OTm3Ti tetrahedra that share  a cornercorner with one O(3)Tm2Ti2 tetrahedra, corners with three equivalent O(5)Tm3Ti tetrahedra, edges with two equivalent O(4)Tm2MgTi2 trigonal bipyramids, and edges with two equivalent O(2)Tm3Ti trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Tm(1), one Tm(2), and one Ti(2) atom. is represented by the CIF file [CIF]
data_Tm4MgTi2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.097
_cell_length_b   5.873
_cell_length_c   10.525
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   68.391
_symmetry_Int_Tables_number   1
_cell_volume   235.481
_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
  Tm  Tm0  1  0.132  0.727  0.928  1.0
  Tm  Tm1  1  0.132  0.727  0.572  1.0
  Tm  Tm2  1  0.868  0.290  0.062  1.0
  Tm  Tm3  1  0.868  0.290  0.438  1.0
  Mg  Mg4  1  0.584  0.948  0.250  1.0
  Ti  Ti5  1  0.218  0.575  0.250  1.0
  Ti  Ti6  1  0.787  0.362  0.750  1.0
  O  O7  1  0.992  0.906  0.378  1.0
  O  O8  1  0.992  0.906  0.122  1.0
  O  O9  1  0.704  0.598  0.906  1.0
  O  O10  1  0.704  0.598  0.594  1.0
  O  O11  1  0.286  0.466  0.750  1.0
  O  O12  1  0.714  0.571  0.250  1.0
  O  O13  1  0.300  0.426  0.073  1.0
  O  O14  1  0.300  0.426  0.427  1.0
  O  O15  1  0.952  0.113  0.624  1.0
  O  O16  1  0.952  0.113  0.876  1.0
[/CIF]
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The compound described by MgTm4Ti2O10 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a distorted T-shaped geometry to one O(4) and two equivalent O(1) atoms. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(1), one O(3), one O(5), one O(6), and two equivalent O(2) atoms to form distorted TmO6 pentagonal pyramids that share  a cornercorner with one Ti(2)O6 octahedra, corners with three equivalent Tm(1)O6 pentagonal pyramids, edges with two equivalent Ti(2)O6 octahedra, and  an edgeedge with one Ti(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 31°. In the second Tm site, Tm(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(6), and two equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted TiO6 pentagonal pyramids that share corners with two equivalent Ti(1)O6 pentagonal pyramids and edges with two equivalent Tm(1)O6 pentagonal pyramids. In the second Ti site, Ti(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Tm(1)O6 pentagonal pyramids, and edges with four equivalent Tm(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 32°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Tm(1), one Tm(2), and one Ti(1) atom. In the second O site, O(2) is bonded to one Tm(2), two equivalent Tm(1), and one Ti(2) atom to form OTm3Ti trigonal pyramids that share  a cornercorner with one O(4)Tm2MgTi2 trigonal bipyramid, corners with three equivalent O(2)Tm3Ti trigonal pyramids, edges with two equivalent O(3)Tm2Ti2 tetrahedra, and edges with two equivalent O(5)Tm3Ti tetrahedra. In the third O site, O(3) is bonded to two equivalent Tm(1) and two equivalent Ti(2) atoms to form distorted OTm2Ti2 tetrahedra that share corners with two equivalent O(3)Tm2Ti2 tetrahedra, corners with two equivalent O(5)Tm3Ti tetrahedra, and edges with four equivalent O(2)Tm3Ti trigonal pyramids. In the fourth O site, O(4) is bonded to one Mg(1), two equivalent Tm(2), and two equivalent Ti(1) atoms to form OTm2MgTi2 trigonal bipyramids that share corners with two equivalent O(4)Tm2MgTi2 trigonal bipyramids, corners with two equivalent O(2)Tm3Ti trigonal pyramids, and edges with four equivalent O(5)Tm3Ti tetrahedra. In the fifth O site, O(5) is bonded to one Tm(1), two equivalent Tm(2), and one Ti(1) atom to form OTm3Ti tetrahedra that share  a cornercorner with one O(3)Tm2Ti2 tetrahedra, corners with three equivalent O(5)Tm3Ti tetrahedra, edges with two equivalent O(4)Tm2MgTi2 trigonal bipyramids, and edges with two equivalent O(2)Tm3Ti trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Tm(1), one Tm(2), and one Ti(2) atom. is represented by the CIF file [CIF]
data_Tm4MgTi2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.097
_cell_length_b   5.873
_cell_length_c   10.525
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   68.391
_symmetry_Int_Tables_number   1
_cell_volume   235.481
_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
  Tm  Tm0  1  0.132  0.727  0.928  1.0
  Tm  Tm1  1  0.132  0.727  0.572  1.0
  Tm  Tm2  1  0.868  0.290  0.062  1.0
  Tm  Tm3  1  0.868  0.290  0.438  1.0
  Mg  Mg4  1  0.584  0.948  0.250  1.0
  Ti  Ti5  1  0.218  0.575  0.250  1.0
  Ti  Ti6  1  0.787  0.362  0.750  1.0
  O  O7  1  0.992  0.906  0.378  1.0
  O  O8  1  0.992  0.906  0.122  1.0
  O  O9  1  0.704  0.598  0.906  1.0
  O  O10  1  0.704  0.598  0.594  1.0
  O  O11  1  0.286  0.466  0.750  1.0
  O  O12  1  0.714  0.571  0.250  1.0
  O  O13  1  0.300  0.426  0.073  1.0
  O  O14  1  0.300  0.426  0.427  1.0
  O  O15  1  0.952  0.113  0.624  1.0
  O  O16  1  0.952  0.113  0.876  1.0
[/CIF]
.