The structure described by MgTb2Cu(GeO3)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted MgO6 octahedra that share corners with four equivalent Tb(1)O7 pentagonal bipyramids, edges with two equivalent Ge(1)O4 tetrahedra, and edges with two equivalent Ge(2)O4 tetrahedra. Tb(1) is bonded to one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Ge(2)O4 tetrahedra, corners with four equivalent Ge(1)O4 tetrahedra, edges with two equivalent Tb(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-42°. Cu(1) is bonded in a square co-planar geometry to two equivalent O(5) and two equivalent O(6) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form GeO4 tetrahedra that share corners with four equivalent Tb(1)O7 pentagonal bipyramids, corners with two equivalent Ge(2)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 octahedra. In the second Ge site, Ge(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form GeO4 tetrahedra that share corners with two equivalent Tb(1)O7 pentagonal bipyramids, corners with two equivalent Ge(1)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and  an edgeedge with one Tb(1)O7 pentagonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Tb(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Tb(1) and one Ge(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Tb(1), one Ge(1), and one Ge(2) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1), one Ge(1), and one Ge(2) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Tb(1), one Cu(1), and one Ge(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Tb(1), one Cu(1), and one Ge(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2MgCu(GeO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.249
_cell_length_b   7.573
_cell_length_c   8.156
_cell_angle_alpha   65.190
_cell_angle_beta   87.720
_cell_angle_gamma   77.167
_symmetry_Int_Tables_number   1
_cell_volume   286.386
_cell_formula_units_Z   1
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  0.033  0.777  0.434  1.0
  Tb  Tb1  1  0.967  0.223  0.566  1.0
  Mg  Mg2  1  0.500  0.000  0.000  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Ge  Ge4  1  0.558  0.832  0.753  1.0
  Ge  Ge5  1  0.442  0.168  0.247  1.0
  Ge  Ge6  1  0.584  0.595  0.214  1.0
  Ge  Ge7  1  0.416  0.405  0.786  1.0
  O  O8  1  0.801  0.925  0.607  1.0
  O  O9  1  0.199  0.075  0.393  1.0
  O  O10  1  0.828  0.558  0.375  1.0
  O  O11  1  0.172  0.442  0.625  1.0
  O  O12  1  0.438  0.666  0.686  1.0
  O  O13  1  0.562  0.334  0.314  1.0
  O  O14  1  0.707  0.723  0.987  1.0
  O  O15  1  0.703  0.207  0.805  1.0
  O  O16  1  0.297  0.793  0.195  1.0
  O  O17  1  0.706  0.991  0.217  1.0
  O  O18  1  0.294  0.009  0.783  1.0
  O  O19  1  0.293  0.277  0.013  1.0
[/CIF]
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The structure described by MgTb2Cu(GeO3)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted MgO6 octahedra that share corners with four equivalent Tb(1)O7 pentagonal bipyramids, edges with two equivalent Ge(1)O4 tetrahedra, and edges with two equivalent Ge(2)O4 tetrahedra. Tb(1) is bonded to one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Ge(2)O4 tetrahedra, corners with four equivalent Ge(1)O4 tetrahedra, edges with two equivalent Tb(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-42°. Cu(1) is bonded in a square co-planar geometry to two equivalent O(5) and two equivalent O(6) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form GeO4 tetrahedra that share corners with four equivalent Tb(1)O7 pentagonal bipyramids, corners with two equivalent Ge(2)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 octahedra. In the second Ge site, Ge(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form GeO4 tetrahedra that share corners with two equivalent Tb(1)O7 pentagonal bipyramids, corners with two equivalent Ge(1)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and  an edgeedge with one Tb(1)O7 pentagonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Tb(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Tb(1) and one Ge(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Tb(1), one Ge(1), and one Ge(2) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1), one Ge(1), and one Ge(2) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Tb(1), one Cu(1), and one Ge(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Tb(1), one Cu(1), and one Ge(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2MgCu(GeO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.249
_cell_length_b   7.573
_cell_length_c   8.156
_cell_angle_alpha   65.190
_cell_angle_beta   87.720
_cell_angle_gamma   77.167
_symmetry_Int_Tables_number   1
_cell_volume   286.386
_cell_formula_units_Z   1
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  0.033  0.777  0.434  1.0
  Tb  Tb1  1  0.967  0.223  0.566  1.0
  Mg  Mg2  1  0.500  0.000  0.000  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Ge  Ge4  1  0.558  0.832  0.753  1.0
  Ge  Ge5  1  0.442  0.168  0.247  1.0
  Ge  Ge6  1  0.584  0.595  0.214  1.0
  Ge  Ge7  1  0.416  0.405  0.786  1.0
  O  O8  1  0.801  0.925  0.607  1.0
  O  O9  1  0.199  0.075  0.393  1.0
  O  O10  1  0.828  0.558  0.375  1.0
  O  O11  1  0.172  0.442  0.625  1.0
  O  O12  1  0.438  0.666  0.686  1.0
  O  O13  1  0.562  0.334  0.314  1.0
  O  O14  1  0.707  0.723  0.987  1.0
  O  O15  1  0.703  0.207  0.805  1.0
  O  O16  1  0.297  0.793  0.195  1.0
  O  O17  1  0.706  0.991  0.217  1.0
  O  O18  1  0.294  0.009  0.783  1.0
  O  O19  1  0.293  0.277  0.013  1.0
[/CIF]
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