The crystal structure described by MgEr4Ti2O10 is Aluminum carbonitride-derived structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form distorted MgO6 octahedra that share corners with four equivalent Ti(1)O5 trigonal bipyramids and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 5-coordinate geometry to one O(2), one O(5), and three equivalent O(3) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one O(5), two equivalent O(1), and three equivalent O(4) atoms. Ti(1) is bonded to one O(1), one O(2), one O(4), and two equivalent O(5) atoms to form TiO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra and corners with two equivalent Ti(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 59°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to two equivalent Er(2) and one Ti(1) atom. In the second O site, O(2) is bonded to two equivalent Mg(1), one Er(1), and one Ti(1) atom to form distorted OErMg2Ti trigonal pyramids that share  a cornercorner with one O(4)Er3Ti tetrahedra, corners with three equivalent O(5)Er2Ti2 tetrahedra, corners with three equivalent O(3)Er3Mg tetrahedra, corners with four equivalent O(2)ErMg2Ti trigonal pyramids, edges with two equivalent O(3)Er3Mg tetrahedra, and  an edgeedge with one O(2)ErMg2Ti trigonal pyramid. In the third O site, O(3) is bonded to one Mg(1) and three equivalent Er(1) atoms to form OEr3Mg tetrahedra that share corners with three equivalent O(5)Er2Ti2 tetrahedra, corners with three equivalent O(3)Er3Mg tetrahedra, corners with three equivalent O(2)ErMg2Ti trigonal pyramids, edges with two equivalent O(3)Er3Mg tetrahedra, and edges with two equivalent O(2)ErMg2Ti trigonal pyramids. In the fourth O site, O(4) is bonded to three equivalent Er(2) and one Ti(1) atom to form OEr3Ti tetrahedra that share  a cornercorner with one O(5)Er2Ti2 tetrahedra, corners with two equivalent O(4)Er3Ti tetrahedra,  a cornercorner with one O(2)ErMg2Ti trigonal pyramid, edges with two equivalent O(5)Er2Ti2 tetrahedra, and edges with two equivalent O(4)Er3Ti tetrahedra. In the fifth O site, O(5) is bonded to one Er(1), one Er(2), and two equivalent Ti(1) atoms to form OEr2Ti2 tetrahedra that share  a cornercorner with one O(4)Er3Ti tetrahedra, corners with two equivalent O(5)Er2Ti2 tetrahedra, corners with three equivalent O(3)Er3Mg tetrahedra, corners with three equivalent O(2)ErMg2Ti trigonal pyramids, and edges with two equivalent O(4)Er3Ti tetrahedra. is represented by the CIF card [CIF]
data_Er4MgTi2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.895
_cell_length_b   5.913
_cell_length_c   11.595
_cell_angle_alpha   78.834
_cell_angle_beta   90.000
_cell_angle_gamma   70.774
_symmetry_Int_Tables_number   1
_cell_volume   246.779
_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
  Er  Er0  1  0.178  0.643  0.882  1.0
  Er  Er1  1  0.149  0.701  0.559  1.0
  Er  Er2  1  0.822  0.357  0.118  1.0
  Er  Er3  1  0.851  0.299  0.441  1.0
  Mg  Mg4  1  0.500  0.000  0.000  1.0
  Ti  Ti5  1  0.134  0.731  0.267  1.0
  Ti  Ti6  1  0.866  0.269  0.733  1.0
  O  O7  1  0.023  0.954  0.377  1.0
  O  O8  1  0.026  0.948  0.122  1.0
  O  O9  1  0.665  0.670  0.965  1.0
  O  O10  1  0.729  0.542  0.578  1.0
  O  O11  1  0.296  0.409  0.747  1.0
  O  O12  1  0.704  0.591  0.253  1.0
  O  O13  1  0.335  0.330  0.035  1.0
  O  O14  1  0.271  0.458  0.422  1.0
  O  O15  1  0.977  0.046  0.623  1.0
  O  O16  1  0.974  0.052  0.878  1.0
[/CIF]
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The crystal structure described by MgEr4Ti2O10 is Aluminum carbonitride-derived structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form distorted MgO6 octahedra that share corners with four equivalent Ti(1)O5 trigonal bipyramids and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 5-coordinate geometry to one O(2), one O(5), and three equivalent O(3) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one O(5), two equivalent O(1), and three equivalent O(4) atoms. Ti(1) is bonded to one O(1), one O(2), one O(4), and two equivalent O(5) atoms to form TiO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra and corners with two equivalent Ti(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 59°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to two equivalent Er(2) and one Ti(1) atom. In the second O site, O(2) is bonded to two equivalent Mg(1), one Er(1), and one Ti(1) atom to form distorted OErMg2Ti trigonal pyramids that share  a cornercorner with one O(4)Er3Ti tetrahedra, corners with three equivalent O(5)Er2Ti2 tetrahedra, corners with three equivalent O(3)Er3Mg tetrahedra, corners with four equivalent O(2)ErMg2Ti trigonal pyramids, edges with two equivalent O(3)Er3Mg tetrahedra, and  an edgeedge with one O(2)ErMg2Ti trigonal pyramid. In the third O site, O(3) is bonded to one Mg(1) and three equivalent Er(1) atoms to form OEr3Mg tetrahedra that share corners with three equivalent O(5)Er2Ti2 tetrahedra, corners with three equivalent O(3)Er3Mg tetrahedra, corners with three equivalent O(2)ErMg2Ti trigonal pyramids, edges with two equivalent O(3)Er3Mg tetrahedra, and edges with two equivalent O(2)ErMg2Ti trigonal pyramids. In the fourth O site, O(4) is bonded to three equivalent Er(2) and one Ti(1) atom to form OEr3Ti tetrahedra that share  a cornercorner with one O(5)Er2Ti2 tetrahedra, corners with two equivalent O(4)Er3Ti tetrahedra,  a cornercorner with one O(2)ErMg2Ti trigonal pyramid, edges with two equivalent O(5)Er2Ti2 tetrahedra, and edges with two equivalent O(4)Er3Ti tetrahedra. In the fifth O site, O(5) is bonded to one Er(1), one Er(2), and two equivalent Ti(1) atoms to form OEr2Ti2 tetrahedra that share  a cornercorner with one O(4)Er3Ti tetrahedra, corners with two equivalent O(5)Er2Ti2 tetrahedra, corners with three equivalent O(3)Er3Mg tetrahedra, corners with three equivalent O(2)ErMg2Ti trigonal pyramids, and edges with two equivalent O(4)Er3Ti tetrahedra. is represented by the CIF card [CIF]
data_Er4MgTi2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.895
_cell_length_b   5.913
_cell_length_c   11.595
_cell_angle_alpha   78.834
_cell_angle_beta   90.000
_cell_angle_gamma   70.774
_symmetry_Int_Tables_number   1
_cell_volume   246.779
_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
  Er  Er0  1  0.178  0.643  0.882  1.0
  Er  Er1  1  0.149  0.701  0.559  1.0
  Er  Er2  1  0.822  0.357  0.118  1.0
  Er  Er3  1  0.851  0.299  0.441  1.0
  Mg  Mg4  1  0.500  0.000  0.000  1.0
  Ti  Ti5  1  0.134  0.731  0.267  1.0
  Ti  Ti6  1  0.866  0.269  0.733  1.0
  O  O7  1  0.023  0.954  0.377  1.0
  O  O8  1  0.026  0.948  0.122  1.0
  O  O9  1  0.665  0.670  0.965  1.0
  O  O10  1  0.729  0.542  0.578  1.0
  O  O11  1  0.296  0.409  0.747  1.0
  O  O12  1  0.704  0.591  0.253  1.0
  O  O13  1  0.335  0.330  0.035  1.0
  O  O14  1  0.271  0.458  0.422  1.0
  O  O15  1  0.977  0.046  0.623  1.0
  O  O16  1  0.974  0.052  0.878  1.0
[/CIF]
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