The material described by Ba2ErInSe5 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one Se(3), one Se(5), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(4) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one Se(2), one Se(5), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(4) atoms. Er(1) is bonded to one Se(1), one Se(5), two equivalent Se(2), and two equivalent Se(3) atoms to form ErSe6 octahedra that share edges with two equivalent Er(1)Se6 octahedra and edges with two equivalent In(1)Se4 trigonal pyramids. In(1) is bonded to one Se(3), one Se(4), and two equivalent Se(5) atoms to form InSe4 trigonal pyramids that share corners with two equivalent In(1)Se4 trigonal pyramids and edges with two equivalent Er(1)Se6 octahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Er(1) atom to form SeBa4Er square pyramids that share corners with two equivalent Se(3)Ba3Er2In octahedra, corners with four equivalent Se(4)Ba4In square pyramids, corners with two equivalent Se(2)Ba3Er2 trigonal bipyramids, edges with three equivalent Se(3)Ba3Er2In octahedra, edges with two equivalent Se(1)Ba4Er square pyramids, edges with two equivalent Se(4)Ba4In square pyramids, and edges with three equivalent Se(2)Ba3Er2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 31°. In the second Se site, Se(2) is bonded to one Ba(2), two equivalent Ba(1), and two equivalent Er(1) atoms to form distorted SeBa3Er2 trigonal bipyramids that share corners with two equivalent Se(3)Ba3Er2In octahedra, corners with two equivalent Se(1)Ba4Er square pyramids, corners with four equivalent Se(4)Ba4In square pyramids, edges with three equivalent Se(3)Ba3Er2In octahedra,  an edgeedge with one Se(4)Ba4In square pyramid, edges with three equivalent Se(1)Ba4Er square pyramids, and edges with two equivalent Se(2)Ba3Er2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 10°. In the third Se site, Se(3) is bonded to one Ba(1), two equivalent Ba(2), two equivalent Er(1), and one In(1) atom to form distorted SeBa3Er2In octahedra that share corners with two equivalent Se(1)Ba4Er square pyramids, corners with four equivalent Se(4)Ba4In square pyramids, corners with two equivalent Se(2)Ba3Er2 trigonal bipyramids, edges with two equivalent Se(3)Ba3Er2In octahedra, edges with three equivalent Se(1)Ba4Er square pyramids, edges with three equivalent Se(2)Ba3Er2 trigonal bipyramids, and  a faceface with one Se(4)Ba4In square pyramid. In the fourth Se site, Se(4) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one In(1) atom to form SeBa4In square pyramids that share corners with four equivalent Se(3)Ba3Er2In octahedra, corners with four equivalent Se(1)Ba4Er square pyramids, corners with four equivalent Se(2)Ba3Er2 trigonal bipyramids, edges with two equivalent Se(1)Ba4Er square pyramids, edges with two equivalent Se(4)Ba4In square pyramids,  an edgeedge with one Se(2)Ba3Er2 trigonal bipyramid, and  a faceface with one Se(3)Ba3Er2In octahedra. The corner-sharing octahedral tilt angles range from 40-67°. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Er(1), and two equivalent In(1) atoms. is represented by the CIF card [CIF]
data_Ba2ErInSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.753
_cell_length_b   9.753
_cell_length_c   13.492
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   154.560
_symmetry_Int_Tables_number   1
_cell_volume   551.326
_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
  Ba  Ba0  1  0.867  0.133  0.187  1.0
  Ba  Ba1  1  0.133  0.867  0.687  1.0
  Ba  Ba2  1  0.882  0.118  0.819  1.0
  Ba  Ba3  1  0.118  0.882  0.319  1.0
  Er  Er4  1  0.788  0.212  0.482  1.0
  Er  Er5  1  0.212  0.788  0.982  1.0
  In  In6  1  0.553  0.447  0.063  1.0
  In  In7  1  0.447  0.553  0.563  1.0
  Se  Se8  1  0.645  0.355  0.500  1.0
  Se  Se9  1  0.355  0.645  1.000  1.0
  Se  Se10  1  0.709  0.291  0.845  1.0
  Se  Se11  1  0.291  0.709  0.345  1.0
  Se  Se12  1  0.687  0.313  0.128  1.0
  Se  Se13  1  0.313  0.687  0.628  1.0
  Se  Se14  1  0.495  0.505  0.234  1.0
  Se  Se15  1  0.505  0.495  0.734  1.0
  Se  Se16  1  0.948  0.052  0.449  1.0
  Se  Se17  1  0.052  0.948  0.949  1.0
[/CIF]
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The material described by Ba2ErInSe5 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one Se(3), one Se(5), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(4) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one Se(2), one Se(5), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(4) atoms. Er(1) is bonded to one Se(1), one Se(5), two equivalent Se(2), and two equivalent Se(3) atoms to form ErSe6 octahedra that share edges with two equivalent Er(1)Se6 octahedra and edges with two equivalent In(1)Se4 trigonal pyramids. In(1) is bonded to one Se(3), one Se(4), and two equivalent Se(5) atoms to form InSe4 trigonal pyramids that share corners with two equivalent In(1)Se4 trigonal pyramids and edges with two equivalent Er(1)Se6 octahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Er(1) atom to form SeBa4Er square pyramids that share corners with two equivalent Se(3)Ba3Er2In octahedra, corners with four equivalent Se(4)Ba4In square pyramids, corners with two equivalent Se(2)Ba3Er2 trigonal bipyramids, edges with three equivalent Se(3)Ba3Er2In octahedra, edges with two equivalent Se(1)Ba4Er square pyramids, edges with two equivalent Se(4)Ba4In square pyramids, and edges with three equivalent Se(2)Ba3Er2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 31°. In the second Se site, Se(2) is bonded to one Ba(2), two equivalent Ba(1), and two equivalent Er(1) atoms to form distorted SeBa3Er2 trigonal bipyramids that share corners with two equivalent Se(3)Ba3Er2In octahedra, corners with two equivalent Se(1)Ba4Er square pyramids, corners with four equivalent Se(4)Ba4In square pyramids, edges with three equivalent Se(3)Ba3Er2In octahedra,  an edgeedge with one Se(4)Ba4In square pyramid, edges with three equivalent Se(1)Ba4Er square pyramids, and edges with two equivalent Se(2)Ba3Er2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 10°. In the third Se site, Se(3) is bonded to one Ba(1), two equivalent Ba(2), two equivalent Er(1), and one In(1) atom to form distorted SeBa3Er2In octahedra that share corners with two equivalent Se(1)Ba4Er square pyramids, corners with four equivalent Se(4)Ba4In square pyramids, corners with two equivalent Se(2)Ba3Er2 trigonal bipyramids, edges with two equivalent Se(3)Ba3Er2In octahedra, edges with three equivalent Se(1)Ba4Er square pyramids, edges with three equivalent Se(2)Ba3Er2 trigonal bipyramids, and  a faceface with one Se(4)Ba4In square pyramid. In the fourth Se site, Se(4) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one In(1) atom to form SeBa4In square pyramids that share corners with four equivalent Se(3)Ba3Er2In octahedra, corners with four equivalent Se(1)Ba4Er square pyramids, corners with four equivalent Se(2)Ba3Er2 trigonal bipyramids, edges with two equivalent Se(1)Ba4Er square pyramids, edges with two equivalent Se(4)Ba4In square pyramids,  an edgeedge with one Se(2)Ba3Er2 trigonal bipyramid, and  a faceface with one Se(3)Ba3Er2In octahedra. The corner-sharing octahedral tilt angles range from 40-67°. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Er(1), and two equivalent In(1) atoms. is represented by the CIF card [CIF]
data_Ba2ErInSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.753
_cell_length_b   9.753
_cell_length_c   13.492
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   154.560
_symmetry_Int_Tables_number   1
_cell_volume   551.326
_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
  Ba  Ba0  1  0.867  0.133  0.187  1.0
  Ba  Ba1  1  0.133  0.867  0.687  1.0
  Ba  Ba2  1  0.882  0.118  0.819  1.0
  Ba  Ba3  1  0.118  0.882  0.319  1.0
  Er  Er4  1  0.788  0.212  0.482  1.0
  Er  Er5  1  0.212  0.788  0.982  1.0
  In  In6  1  0.553  0.447  0.063  1.0
  In  In7  1  0.447  0.553  0.563  1.0
  Se  Se8  1  0.645  0.355  0.500  1.0
  Se  Se9  1  0.355  0.645  1.000  1.0
  Se  Se10  1  0.709  0.291  0.845  1.0
  Se  Se11  1  0.291  0.709  0.345  1.0
  Se  Se12  1  0.687  0.313  0.128  1.0
  Se  Se13  1  0.313  0.687  0.628  1.0
  Se  Se14  1  0.495  0.505  0.234  1.0
  Se  Se15  1  0.505  0.495  0.734  1.0
  Se  Se16  1  0.948  0.052  0.449  1.0
  Se  Se17  1  0.052  0.948  0.949  1.0
[/CIF]
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