The compound described by Er4BO7Cl crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), one O(7), and one Cl(1) atom. In the second Er site, Er(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(5), two equivalent O(4), and one Cl(1) atom. In the third Er site, Er(3) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(7), two equivalent O(1), and one Cl(1) atom. In the fourth Er site, Er(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent Cl(1) atoms. B(1) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(3) is bonded to one Er(1), one Er(2), one Er(3), and one Er(4) atom to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the second O site, O(4) is bonded to one Er(3), one Er(4), and two equivalent Er(2) atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the third O site, O(5) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one B(1) atom. In the fourth O site, O(6) is bonded in a distorted trigonal planar geometry to one Er(1), one Er(4), and one B(1) atom. In the fifth O site, O(7) is bonded in a distorted single-bond geometry to one Er(1), one Er(3), one Er(4), and one B(1) atom. In the sixth O site, O(1) is bonded to one Er(1), one Er(2), and two equivalent Er(3) atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the seventh O site, O(2) is bonded to one Er(1), one Er(2), one Er(3), and one Er(4) atom to form a mixture of corner and edge-sharing OEr4 tetrahedra. Cl(1) is bonded in a 5-coordinate geometry to one Er(1), one Er(2), one Er(3), and two equivalent Er(4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er4BClO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.926
_cell_length_b   8.452
_cell_length_c   12.036
_cell_angle_alpha   60.742
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   703.407
_cell_formula_units_Z   4
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  0.624  0.796  0.222  1.0
  Er  Er1  1  0.876  0.796  0.722  1.0
  Er  Er2  1  0.376  0.204  0.778  1.0
  Er  Er3  1  0.124  0.204  0.278  1.0
  Er  Er4  1  0.617  0.426  0.908  1.0
  Er  Er5  1  0.883  0.426  0.408  1.0
  Er  Er6  1  0.383  0.574  0.092  1.0
  Er  Er7  1  0.117  0.574  0.592  1.0
  Er  Er8  1  0.640  0.568  0.581  1.0
  Er  Er9  1  0.860  0.568  0.081  1.0
  Er  Er10  1  0.360  0.432  0.419  1.0
  Er  Er11  1  0.140  0.432  0.919  1.0
  Er  Er12  1  0.614  0.182  0.279  1.0
  Er  Er13  1  0.886  0.182  0.779  1.0
  Er  Er14  1  0.386  0.818  0.721  1.0
  Er  Er15  1  0.114  0.818  0.221  1.0
  B  B16  1  0.869  0.870  0.414  1.0
  B  B17  1  0.631  0.870  0.914  1.0
  B  B18  1  0.131  0.130  0.586  1.0
  B  B19  1  0.369  0.130  0.086  1.0
  Cl  Cl20  1  0.847  0.119  0.031  1.0
  Cl  Cl21  1  0.653  0.119  0.531  1.0
  Cl  Cl22  1  0.153  0.881  0.969  1.0
  Cl  Cl23  1  0.347  0.881  0.469  1.0
  O  O24  1  0.622  0.540  0.403  1.0
  O  O25  1  0.878  0.540  0.903  1.0
  O  O26  1  0.378  0.460  0.597  1.0
  O  O27  1  0.122  0.460  0.097  1.0
  O  O28  1  0.638  0.311  0.772  1.0
  O  O29  1  0.862  0.311  0.272  1.0
  O  O30  1  0.362  0.689  0.228  1.0
  O  O31  1  0.138  0.689  0.728  1.0
  O  O32  1  0.617  0.680  0.718  1.0
  O  O33  1  0.883  0.680  0.218  1.0
  O  O34  1  0.383  0.320  0.282  1.0
  O  O35  1  0.117  0.320  0.782  1.0
  O  O36  1  0.621  0.425  0.093  1.0
  O  O37  1  0.879  0.425  0.593  1.0
  O  O38  1  0.379  0.575  0.907  1.0
  O  O39  1  0.121  0.575  0.407  1.0
  O  O40  1  0.891  0.773  0.544  1.0
  O  O41  1  0.609  0.773  0.044  1.0
  O  O42  1  0.109  0.227  0.456  1.0
  O  O43  1  0.391  0.227  0.956  1.0
  O  O44  1  0.003  0.940  0.333  1.0
  O  O45  1  0.497  0.940  0.833  1.0
  O  O46  1  0.997  0.060  0.667  1.0
  O  O47  1  0.503  0.060  0.167  1.0
  O  O48  1  0.709  0.887  0.366  1.0
  O  O49  1  0.791  0.887  0.866  1.0
  O  O50  1  0.291  0.113  0.634  1.0
  O  O51  1  0.209  0.113  0.134  1.0
[/CIF]
.
The compound described by Er4BO7Cl crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), one O(7), and one Cl(1) atom. In the second Er site, Er(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(5), two equivalent O(4), and one Cl(1) atom. In the third Er site, Er(3) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(7), two equivalent O(1), and one Cl(1) atom. In the fourth Er site, Er(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent Cl(1) atoms. B(1) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(3) is bonded to one Er(1), one Er(2), one Er(3), and one Er(4) atom to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the second O site, O(4) is bonded to one Er(3), one Er(4), and two equivalent Er(2) atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the third O site, O(5) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one B(1) atom. In the fourth O site, O(6) is bonded in a distorted trigonal planar geometry to one Er(1), one Er(4), and one B(1) atom. In the fifth O site, O(7) is bonded in a distorted single-bond geometry to one Er(1), one Er(3), one Er(4), and one B(1) atom. In the sixth O site, O(1) is bonded to one Er(1), one Er(2), and two equivalent Er(3) atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the seventh O site, O(2) is bonded to one Er(1), one Er(2), one Er(3), and one Er(4) atom to form a mixture of corner and edge-sharing OEr4 tetrahedra. Cl(1) is bonded in a 5-coordinate geometry to one Er(1), one Er(2), one Er(3), and two equivalent Er(4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er4BClO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.926
_cell_length_b   8.452
_cell_length_c   12.036
_cell_angle_alpha   60.742
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   703.407
_cell_formula_units_Z   4
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  0.624  0.796  0.222  1.0
  Er  Er1  1  0.876  0.796  0.722  1.0
  Er  Er2  1  0.376  0.204  0.778  1.0
  Er  Er3  1  0.124  0.204  0.278  1.0
  Er  Er4  1  0.617  0.426  0.908  1.0
  Er  Er5  1  0.883  0.426  0.408  1.0
  Er  Er6  1  0.383  0.574  0.092  1.0
  Er  Er7  1  0.117  0.574  0.592  1.0
  Er  Er8  1  0.640  0.568  0.581  1.0
  Er  Er9  1  0.860  0.568  0.081  1.0
  Er  Er10  1  0.360  0.432  0.419  1.0
  Er  Er11  1  0.140  0.432  0.919  1.0
  Er  Er12  1  0.614  0.182  0.279  1.0
  Er  Er13  1  0.886  0.182  0.779  1.0
  Er  Er14  1  0.386  0.818  0.721  1.0
  Er  Er15  1  0.114  0.818  0.221  1.0
  B  B16  1  0.869  0.870  0.414  1.0
  B  B17  1  0.631  0.870  0.914  1.0
  B  B18  1  0.131  0.130  0.586  1.0
  B  B19  1  0.369  0.130  0.086  1.0
  Cl  Cl20  1  0.847  0.119  0.031  1.0
  Cl  Cl21  1  0.653  0.119  0.531  1.0
  Cl  Cl22  1  0.153  0.881  0.969  1.0
  Cl  Cl23  1  0.347  0.881  0.469  1.0
  O  O24  1  0.622  0.540  0.403  1.0
  O  O25  1  0.878  0.540  0.903  1.0
  O  O26  1  0.378  0.460  0.597  1.0
  O  O27  1  0.122  0.460  0.097  1.0
  O  O28  1  0.638  0.311  0.772  1.0
  O  O29  1  0.862  0.311  0.272  1.0
  O  O30  1  0.362  0.689  0.228  1.0
  O  O31  1  0.138  0.689  0.728  1.0
  O  O32  1  0.617  0.680  0.718  1.0
  O  O33  1  0.883  0.680  0.218  1.0
  O  O34  1  0.383  0.320  0.282  1.0
  O  O35  1  0.117  0.320  0.782  1.0
  O  O36  1  0.621  0.425  0.093  1.0
  O  O37  1  0.879  0.425  0.593  1.0
  O  O38  1  0.379  0.575  0.907  1.0
  O  O39  1  0.121  0.575  0.407  1.0
  O  O40  1  0.891  0.773  0.544  1.0
  O  O41  1  0.609  0.773  0.044  1.0
  O  O42  1  0.109  0.227  0.456  1.0
  O  O43  1  0.391  0.227  0.956  1.0
  O  O44  1  0.003  0.940  0.333  1.0
  O  O45  1  0.497  0.940  0.833  1.0
  O  O46  1  0.997  0.060  0.667  1.0
  O  O47  1  0.503  0.060  0.167  1.0
  O  O48  1  0.709  0.887  0.366  1.0
  O  O49  1  0.791  0.887  0.866  1.0
  O  O50  1  0.291  0.113  0.634  1.0
  O  O51  1  0.209  0.113  0.134  1.0
[/CIF]
.