The material structure described by Er2CO7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 8-coordinate geometry to one O(3), one O(4), one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms. In the second Er site, Er(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(7), two equivalent O(5), and two equivalent O(6) atoms. C(1) is bonded in a trigonal planar geometry to one O(3), one O(4), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(6) is bonded in a trigonal planar geometry to one Er(1) and two equivalent Er(2) atoms. In the second O site, O(7) is bonded in a distorted water-like geometry to one Er(2) and one C(1) atom. In the third O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Er(2) and two equivalent Er(1) atoms. In the fourth O site, O(2) is bonded in a trigonal non-coplanar geometry to one Er(2) and two equivalent Er(1) atoms. In the fifth O site, O(3) is bonded in a bent 150 degrees geometry to one Er(1) and one C(1) atom. In the sixth O site, O(4) is bonded in a 3-coordinate geometry to one Er(1), one Er(2), and one C(1) atom. In the seventh O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Er(1) and two equivalent Er(2) atoms. is represented by the CIF file [CIF]
data_Er2CO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.917
_cell_length_b   6.383
_cell_length_c   16.055
_cell_angle_alpha   84.536
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   603.609
_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  0.233  0.925  0.576  1.0
  Er  Er1  1  0.767  0.075  0.424  1.0
  Er  Er2  1  0.733  0.075  0.924  1.0
  Er  Er3  1  0.267  0.925  0.076  1.0
  Er  Er4  1  0.233  0.897  0.823  1.0
  Er  Er5  1  0.767  0.103  0.177  1.0
  Er  Er6  1  0.733  0.103  0.677  1.0
  Er  Er7  1  0.267  0.897  0.323  1.0
  C  C8  1  0.423  0.426  0.618  1.0
  C  C9  1  0.577  0.574  0.382  1.0
  C  C10  1  0.923  0.574  0.882  1.0
  C  C11  1  0.077  0.426  0.118  1.0
  O  O12  1  0.878  0.924  0.052  1.0
  O  O13  1  0.122  0.076  0.948  1.0
  O  O14  1  0.378  0.076  0.448  1.0
  O  O15  1  0.622  0.924  0.552  1.0
  O  O16  1  0.409  0.865  0.951  1.0
  O  O17  1  0.591  0.135  0.049  1.0
  O  O18  1  0.909  0.135  0.549  1.0
  O  O19  1  0.091  0.865  0.451  1.0
  O  O20  1  0.289  0.576  0.595  1.0
  O  O21  1  0.711  0.424  0.405  1.0
  O  O22  1  0.789  0.424  0.905  1.0
  O  O23  1  0.211  0.576  0.095  1.0
  O  O24  1  0.854  0.769  0.879  1.0
  O  O25  1  0.146  0.231  0.121  1.0
  O  O26  1  0.354  0.231  0.621  1.0
  O  O27  1  0.646  0.769  0.379  1.0
  O  O28  1  0.483  0.853  0.721  1.0
  O  O29  1  0.517  0.147  0.279  1.0
  O  O30  1  0.983  0.147  0.779  1.0
  O  O31  1  0.017  0.853  0.221  1.0
  O  O32  1  0.043  0.893  0.700  1.0
  O  O33  1  0.957  0.107  0.300  1.0
  O  O34  1  0.543  0.107  0.800  1.0
  O  O35  1  0.457  0.893  0.200  1.0
  O  O36  1  0.129  0.547  0.860  1.0
  O  O37  1  0.871  0.453  0.140  1.0
  O  O38  1  0.629  0.453  0.640  1.0
  O  O39  1  0.371  0.547  0.360  1.0
[/CIF]
.
The material structure described by Er2CO7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 8-coordinate geometry to one O(3), one O(4), one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms. In the second Er site, Er(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(7), two equivalent O(5), and two equivalent O(6) atoms. C(1) is bonded in a trigonal planar geometry to one O(3), one O(4), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(6) is bonded in a trigonal planar geometry to one Er(1) and two equivalent Er(2) atoms. In the second O site, O(7) is bonded in a distorted water-like geometry to one Er(2) and one C(1) atom. In the third O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Er(2) and two equivalent Er(1) atoms. In the fourth O site, O(2) is bonded in a trigonal non-coplanar geometry to one Er(2) and two equivalent Er(1) atoms. In the fifth O site, O(3) is bonded in a bent 150 degrees geometry to one Er(1) and one C(1) atom. In the sixth O site, O(4) is bonded in a 3-coordinate geometry to one Er(1), one Er(2), and one C(1) atom. In the seventh O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Er(1) and two equivalent Er(2) atoms. is represented by the CIF file [CIF]
data_Er2CO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.917
_cell_length_b   6.383
_cell_length_c   16.055
_cell_angle_alpha   84.536
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   603.609
_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  0.233  0.925  0.576  1.0
  Er  Er1  1  0.767  0.075  0.424  1.0
  Er  Er2  1  0.733  0.075  0.924  1.0
  Er  Er3  1  0.267  0.925  0.076  1.0
  Er  Er4  1  0.233  0.897  0.823  1.0
  Er  Er5  1  0.767  0.103  0.177  1.0
  Er  Er6  1  0.733  0.103  0.677  1.0
  Er  Er7  1  0.267  0.897  0.323  1.0
  C  C8  1  0.423  0.426  0.618  1.0
  C  C9  1  0.577  0.574  0.382  1.0
  C  C10  1  0.923  0.574  0.882  1.0
  C  C11  1  0.077  0.426  0.118  1.0
  O  O12  1  0.878  0.924  0.052  1.0
  O  O13  1  0.122  0.076  0.948  1.0
  O  O14  1  0.378  0.076  0.448  1.0
  O  O15  1  0.622  0.924  0.552  1.0
  O  O16  1  0.409  0.865  0.951  1.0
  O  O17  1  0.591  0.135  0.049  1.0
  O  O18  1  0.909  0.135  0.549  1.0
  O  O19  1  0.091  0.865  0.451  1.0
  O  O20  1  0.289  0.576  0.595  1.0
  O  O21  1  0.711  0.424  0.405  1.0
  O  O22  1  0.789  0.424  0.905  1.0
  O  O23  1  0.211  0.576  0.095  1.0
  O  O24  1  0.854  0.769  0.879  1.0
  O  O25  1  0.146  0.231  0.121  1.0
  O  O26  1  0.354  0.231  0.621  1.0
  O  O27  1  0.646  0.769  0.379  1.0
  O  O28  1  0.483  0.853  0.721  1.0
  O  O29  1  0.517  0.147  0.279  1.0
  O  O30  1  0.983  0.147  0.779  1.0
  O  O31  1  0.017  0.853  0.221  1.0
  O  O32  1  0.043  0.893  0.700  1.0
  O  O33  1  0.957  0.107  0.300  1.0
  O  O34  1  0.543  0.107  0.800  1.0
  O  O35  1  0.457  0.893  0.200  1.0
  O  O36  1  0.129  0.547  0.860  1.0
  O  O37  1  0.871  0.453  0.140  1.0
  O  O38  1  0.629  0.453  0.640  1.0
  O  O39  1  0.371  0.547  0.360  1.0
[/CIF]
.