The material structure described by TbFeGe2O7 crystallizes in the monoclinic C2/m space group. Tb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form distorted FeO6 octahedra that share corners with four equivalent Ge(1)O4 tetrahedra and  an edgeedge with one Fe(1)O6 octahedra. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(2), one O(3), and two equivalent O(5) atoms to form GeO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-54°. In the second Ge site, Ge(2) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Tb(1), one Fe(1), and one Ge(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Fe(1), one Ge(1), and one Ge(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ge(1) and one Ge(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Tb(1) and one Ge(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Tb(1), one Fe(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_TbFeGe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.942
_cell_length_b   6.942
_cell_length_c   6.780
_cell_angle_alpha   68.834
_cell_angle_beta   68.834
_cell_angle_gamma   76.952
_symmetry_Int_Tables_number   1
_cell_volume   282.446
_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  0.211  0.789  0.000  1.0
  Tb  Tb1  1  0.789  0.211  0.000  1.0
  Fe  Fe2  1  0.303  0.697  0.500  1.0
  Fe  Fe3  1  0.697  0.303  0.500  1.0
  Ge  Ge4  1  0.221  0.221  0.480  1.0
  Ge  Ge5  1  0.779  0.779  0.520  1.0
  Ge  Ge6  1  0.698  0.698  0.077  1.0
  Ge  Ge7  1  0.302  0.302  0.923  1.0
  O  O8  1  0.433  0.791  0.172  1.0
  O  O9  1  0.209  0.567  0.828  1.0
  O  O10  1  0.567  0.209  0.828  1.0
  O  O11  1  0.791  0.433  0.172  1.0
  O  O12  1  0.368  0.368  0.534  1.0
  O  O13  1  0.632  0.632  0.466  1.0
  O  O14  1  0.318  0.318  0.181  1.0
  O  O15  1  0.682  0.682  0.819  1.0
  O  O16  1  0.131  0.131  0.966  1.0
  O  O17  1  0.869  0.869  0.034  1.0
  O  O18  1  0.276  0.948  0.595  1.0
  O  O19  1  0.052  0.724  0.405  1.0
  O  O20  1  0.724  0.052  0.405  1.0
  O  O21  1  0.948  0.276  0.595  1.0
[/CIF]
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The material structure described by TbFeGe2O7 crystallizes in the monoclinic C2/m space group. Tb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form distorted FeO6 octahedra that share corners with four equivalent Ge(1)O4 tetrahedra and  an edgeedge with one Fe(1)O6 octahedra. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(2), one O(3), and two equivalent O(5) atoms to form GeO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-54°. In the second Ge site, Ge(2) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Tb(1), one Fe(1), and one Ge(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Fe(1), one Ge(1), and one Ge(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ge(1) and one Ge(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Tb(1) and one Ge(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Tb(1), one Fe(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_TbFeGe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.942
_cell_length_b   6.942
_cell_length_c   6.780
_cell_angle_alpha   68.834
_cell_angle_beta   68.834
_cell_angle_gamma   76.952
_symmetry_Int_Tables_number   1
_cell_volume   282.446
_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  0.211  0.789  0.000  1.0
  Tb  Tb1  1  0.789  0.211  0.000  1.0
  Fe  Fe2  1  0.303  0.697  0.500  1.0
  Fe  Fe3  1  0.697  0.303  0.500  1.0
  Ge  Ge4  1  0.221  0.221  0.480  1.0
  Ge  Ge5  1  0.779  0.779  0.520  1.0
  Ge  Ge6  1  0.698  0.698  0.077  1.0
  Ge  Ge7  1  0.302  0.302  0.923  1.0
  O  O8  1  0.433  0.791  0.172  1.0
  O  O9  1  0.209  0.567  0.828  1.0
  O  O10  1  0.567  0.209  0.828  1.0
  O  O11  1  0.791  0.433  0.172  1.0
  O  O12  1  0.368  0.368  0.534  1.0
  O  O13  1  0.632  0.632  0.466  1.0
  O  O14  1  0.318  0.318  0.181  1.0
  O  O15  1  0.682  0.682  0.819  1.0
  O  O16  1  0.131  0.131  0.966  1.0
  O  O17  1  0.869  0.869  0.034  1.0
  O  O18  1  0.276  0.948  0.595  1.0
  O  O19  1  0.052  0.724  0.405  1.0
  O  O20  1  0.724  0.052  0.405  1.0
  O  O21  1  0.948  0.276  0.595  1.0
[/CIF]
.