The structure described by Tb2Cu(GeO4)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. In the second Tb site, Tb(2) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(5), one O(7), one O(8), and one O(9) atom. Cu(1) is bonded in a 4-coordinate geometry to one O(10), one O(2), one O(4), one O(8), and two equivalent O(1) atoms. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a tetrahedral geometry to one O(6), one O(9), and two equivalent O(2) atoms. In the second Ge site, Ge(2) is bonded to one O(1), one O(10), one O(4), one O(5), and one O(8) atom to form corner-sharing GeO5 trigonal bipyramids. In the third Ge site, Ge(3) is bonded to one O(3), one O(7), and two equivalent O(5) atoms to form corner-sharing GeO4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(9) is bonded in a trigonal planar geometry to two equivalent Tb(2) and one Ge(1) atom. In the second O site, O(10) is bonded to one Tb(1), one Tb(2), one Cu(1), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OTb2CuGe trigonal pyramids. In the third O site, O(1) is bonded in a 5-coordinate geometry to one Tb(1), one Tb(2), two equivalent Cu(1), and one Ge(2) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Tb(1), one Tb(2), one Cu(1), and one Ge(1) atom. In the fifth O site, O(3) is bonded in a trigonal planar geometry to two equivalent Tb(1) and one Ge(3) atom. In the sixth O site, O(4) is bonded to one Tb(1), one Tb(2), one Cu(1), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OTb2CuGe trigonal pyramids. In the seventh O site, O(5) is bonded in a 4-coordinate geometry to one Tb(1), one Tb(2), one Ge(2), and one Ge(3) atom. In the eighth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Tb(1) and one Ge(1) atom. In the ninth O site, O(7) is bonded in a distorted trigonal planar geometry to two equivalent Tb(2) and one Ge(3) atom. In the tenth O site, O(8) is bonded to one Tb(1), one Tb(2), one Cu(1), and one Ge(2) atom to form a mixture of corner and edge-sharing OTb2CuGe trigonal pyramids. is represented by the CIF file [CIF]
data_Tb2Cu(GeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.973
_cell_length_b   8.973
_cell_length_c   5.155
_cell_angle_alpha   73.681
_cell_angle_beta   73.681
_cell_angle_gamma   114.885
_symmetry_Int_Tables_number   1
_cell_volume   321.153
_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
  Tb  Tb0  1  0.460  0.701  0.184  1.0
  Tb  Tb1  1  0.701  0.460  0.184  1.0
  Tb  Tb2  1  0.198  0.956  0.678  1.0
  Tb  Tb3  1  0.956  0.198  0.678  1.0
  Cu  Cu4  1  0.660  0.074  0.379  1.0
  Cu  Cu5  1  0.074  0.660  0.379  1.0
  Ge  Ge6  1  0.837  0.837  0.375  1.0
  Ge  Ge7  1  0.532  0.112  0.919  1.0
  Ge  Ge8  1  0.112  0.532  0.919  1.0
  Ge  Ge9  1  0.333  0.333  0.977  1.0
  O  O10  1  0.374  0.906  0.925  1.0
  O  O11  1  0.906  0.374  0.925  1.0
  O  O12  1  0.748  0.936  0.583  1.0
  O  O13  1  0.936  0.748  0.583  1.0
  O  O14  1  0.507  0.507  0.011  1.0
  O  O15  1  0.735  0.252  0.551  1.0
  O  O16  1  0.252  0.735  0.551  1.0
  O  O17  1  0.427  0.242  0.755  1.0
  O  O18  1  0.242  0.427  0.755  1.0
  O  O19  1  0.664  0.664  0.336  1.0
  O  O20  1  0.164  0.164  0.354  1.0
  O  O21  1  0.502  0.161  0.243  1.0
  O  O22  1  0.161  0.502  0.243  1.0
  O  O23  1  0.003  0.003  0.989  1.0
  O  O24  1  0.654  0.997  0.071  1.0
  O  O25  1  0.997  0.654  0.071  1.0
[/CIF]
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The structure described by Tb2Cu(GeO4)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. In the second Tb site, Tb(2) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(5), one O(7), one O(8), and one O(9) atom. Cu(1) is bonded in a 4-coordinate geometry to one O(10), one O(2), one O(4), one O(8), and two equivalent O(1) atoms. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a tetrahedral geometry to one O(6), one O(9), and two equivalent O(2) atoms. In the second Ge site, Ge(2) is bonded to one O(1), one O(10), one O(4), one O(5), and one O(8) atom to form corner-sharing GeO5 trigonal bipyramids. In the third Ge site, Ge(3) is bonded to one O(3), one O(7), and two equivalent O(5) atoms to form corner-sharing GeO4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(9) is bonded in a trigonal planar geometry to two equivalent Tb(2) and one Ge(1) atom. In the second O site, O(10) is bonded to one Tb(1), one Tb(2), one Cu(1), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OTb2CuGe trigonal pyramids. In the third O site, O(1) is bonded in a 5-coordinate geometry to one Tb(1), one Tb(2), two equivalent Cu(1), and one Ge(2) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Tb(1), one Tb(2), one Cu(1), and one Ge(1) atom. In the fifth O site, O(3) is bonded in a trigonal planar geometry to two equivalent Tb(1) and one Ge(3) atom. In the sixth O site, O(4) is bonded to one Tb(1), one Tb(2), one Cu(1), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OTb2CuGe trigonal pyramids. In the seventh O site, O(5) is bonded in a 4-coordinate geometry to one Tb(1), one Tb(2), one Ge(2), and one Ge(3) atom. In the eighth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Tb(1) and one Ge(1) atom. In the ninth O site, O(7) is bonded in a distorted trigonal planar geometry to two equivalent Tb(2) and one Ge(3) atom. In the tenth O site, O(8) is bonded to one Tb(1), one Tb(2), one Cu(1), and one Ge(2) atom to form a mixture of corner and edge-sharing OTb2CuGe trigonal pyramids. is represented by the CIF file [CIF]
data_Tb2Cu(GeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.973
_cell_length_b   8.973
_cell_length_c   5.155
_cell_angle_alpha   73.681
_cell_angle_beta   73.681
_cell_angle_gamma   114.885
_symmetry_Int_Tables_number   1
_cell_volume   321.153
_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
  Tb  Tb0  1  0.460  0.701  0.184  1.0
  Tb  Tb1  1  0.701  0.460  0.184  1.0
  Tb  Tb2  1  0.198  0.956  0.678  1.0
  Tb  Tb3  1  0.956  0.198  0.678  1.0
  Cu  Cu4  1  0.660  0.074  0.379  1.0
  Cu  Cu5  1  0.074  0.660  0.379  1.0
  Ge  Ge6  1  0.837  0.837  0.375  1.0
  Ge  Ge7  1  0.532  0.112  0.919  1.0
  Ge  Ge8  1  0.112  0.532  0.919  1.0
  Ge  Ge9  1  0.333  0.333  0.977  1.0
  O  O10  1  0.374  0.906  0.925  1.0
  O  O11  1  0.906  0.374  0.925  1.0
  O  O12  1  0.748  0.936  0.583  1.0
  O  O13  1  0.936  0.748  0.583  1.0
  O  O14  1  0.507  0.507  0.011  1.0
  O  O15  1  0.735  0.252  0.551  1.0
  O  O16  1  0.252  0.735  0.551  1.0
  O  O17  1  0.427  0.242  0.755  1.0
  O  O18  1  0.242  0.427  0.755  1.0
  O  O19  1  0.664  0.664  0.336  1.0
  O  O20  1  0.164  0.164  0.354  1.0
  O  O21  1  0.502  0.161  0.243  1.0
  O  O22  1  0.161  0.502  0.243  1.0
  O  O23  1  0.003  0.003  0.989  1.0
  O  O24  1  0.654  0.997  0.071  1.0
  O  O25  1  0.997  0.654  0.071  1.0
[/CIF]
.