The structure described by Er2TiO5 crystallizes in the monoclinic C2/c space group. Er(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(2) atoms. Ti(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Er(1) and one Ti(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Er(1) and one Ti(1) atom. In the third O site, O(3) is bonded to two equivalent Er(1) and two equivalent Ti(1) atoms to form distorted corner-sharing OEr2Ti2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2TiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.367
_cell_length_b   6.367
_cell_length_c   7.508
_cell_angle_alpha   68.696
_cell_angle_beta   68.696
_cell_angle_gamma   48.744
_symmetry_Int_Tables_number   1
_cell_volume   209.845
_cell_formula_units_Z   2
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  0.371  0.353  0.250  1.0
  Er  Er1  1  0.647  0.629  0.250  1.0
  Er  Er2  1  0.353  0.371  0.750  1.0
  Er  Er3  1  0.629  0.647  0.750  1.0
  Ti  Ti4  1  0.000  0.000  0.000  1.0
  Ti  Ti5  1  0.000  0.000  0.500  1.0
  O  O6  1  0.973  0.687  0.140  1.0
  O  O7  1  0.248  0.609  0.455  1.0
  O  O8  1  0.609  0.248  0.955  1.0
  O  O9  1  0.313  0.027  0.360  1.0
  O  O10  1  0.687  0.973  0.640  1.0
  O  O11  1  0.831  0.169  0.250  1.0
  O  O12  1  0.391  0.752  0.045  1.0
  O  O13  1  0.752  0.391  0.545  1.0
  O  O14  1  0.027  0.313  0.860  1.0
  O  O15  1  0.169  0.831  0.750  1.0
[/CIF]
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The structure described by Er2TiO5 crystallizes in the monoclinic C2/c space group. Er(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(2) atoms. Ti(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Er(1) and one Ti(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Er(1) and one Ti(1) atom. In the third O site, O(3) is bonded to two equivalent Er(1) and two equivalent Ti(1) atoms to form distorted corner-sharing OEr2Ti2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2TiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.367
_cell_length_b   6.367
_cell_length_c   7.508
_cell_angle_alpha   68.696
_cell_angle_beta   68.696
_cell_angle_gamma   48.744
_symmetry_Int_Tables_number   1
_cell_volume   209.845
_cell_formula_units_Z   2
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  0.371  0.353  0.250  1.0
  Er  Er1  1  0.647  0.629  0.250  1.0
  Er  Er2  1  0.353  0.371  0.750  1.0
  Er  Er3  1  0.629  0.647  0.750  1.0
  Ti  Ti4  1  0.000  0.000  0.000  1.0
  Ti  Ti5  1  0.000  0.000  0.500  1.0
  O  O6  1  0.973  0.687  0.140  1.0
  O  O7  1  0.248  0.609  0.455  1.0
  O  O8  1  0.609  0.248  0.955  1.0
  O  O9  1  0.313  0.027  0.360  1.0
  O  O10  1  0.687  0.973  0.640  1.0
  O  O11  1  0.831  0.169  0.250  1.0
  O  O12  1  0.391  0.752  0.045  1.0
  O  O13  1  0.752  0.391  0.545  1.0
  O  O14  1  0.027  0.313  0.860  1.0
  O  O15  1  0.169  0.831  0.750  1.0
[/CIF]
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