The structure described by Al2Ge2O7 crystallizes in the monoclinic C2/c space group. Al(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form AlO5 trigonal bipyramids that share corners with five equivalent Ge(1)O4 tetrahedra and edges with two equivalent Al(1)O5 trigonal bipyramids. Ge(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form GeO4 tetrahedra that share  a cornercorner with one Ge(1)O4 tetrahedra and corners with five equivalent Al(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Ge(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Ge(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Al(1) and one Ge(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al2Ge2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.270
_cell_length_b   5.270
_cell_length_c   9.724
_cell_angle_alpha   76.280
_cell_angle_beta   76.280
_cell_angle_gamma   94.473
_symmetry_Int_Tables_number   1
_cell_volume   252.259
_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
  Al  Al0  1  0.406  0.252  0.979  1.0
  Al  Al1  1  0.748  0.594  0.521  1.0
  Al  Al2  1  0.594  0.748  0.021  1.0
  Al  Al3  1  0.252  0.406  0.479  1.0
  Ge  Ge4  1  0.489  0.993  0.706  1.0
  Ge  Ge5  1  0.007  0.511  0.794  1.0
  Ge  Ge6  1  0.511  0.007  0.294  1.0
  Ge  Ge7  1  0.993  0.489  0.206  1.0
  O  O8  1  0.562  0.017  0.872  1.0
  O  O9  1  0.983  0.438  0.628  1.0
  O  O10  1  0.438  0.983  0.128  1.0
  O  O11  1  0.017  0.562  0.372  1.0
  O  O12  1  0.482  0.316  0.602  1.0
  O  O13  1  0.684  0.518  0.898  1.0
  O  O14  1  0.518  0.684  0.398  1.0
  O  O15  1  0.316  0.482  0.102  1.0
  O  O16  1  0.835  0.165  0.250  1.0
  O  O17  1  0.165  0.835  0.750  1.0
  O  O18  1  0.854  0.718  0.102  1.0
  O  O19  1  0.282  0.146  0.398  1.0
  O  O20  1  0.146  0.282  0.898  1.0
  O  O21  1  0.718  0.854  0.602  1.0
[/CIF]
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The structure described by Al2Ge2O7 crystallizes in the monoclinic C2/c space group. Al(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form AlO5 trigonal bipyramids that share corners with five equivalent Ge(1)O4 tetrahedra and edges with two equivalent Al(1)O5 trigonal bipyramids. Ge(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form GeO4 tetrahedra that share  a cornercorner with one Ge(1)O4 tetrahedra and corners with five equivalent Al(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Ge(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Ge(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Al(1) and one Ge(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al2Ge2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.270
_cell_length_b   5.270
_cell_length_c   9.724
_cell_angle_alpha   76.280
_cell_angle_beta   76.280
_cell_angle_gamma   94.473
_symmetry_Int_Tables_number   1
_cell_volume   252.259
_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
  Al  Al0  1  0.406  0.252  0.979  1.0
  Al  Al1  1  0.748  0.594  0.521  1.0
  Al  Al2  1  0.594  0.748  0.021  1.0
  Al  Al3  1  0.252  0.406  0.479  1.0
  Ge  Ge4  1  0.489  0.993  0.706  1.0
  Ge  Ge5  1  0.007  0.511  0.794  1.0
  Ge  Ge6  1  0.511  0.007  0.294  1.0
  Ge  Ge7  1  0.993  0.489  0.206  1.0
  O  O8  1  0.562  0.017  0.872  1.0
  O  O9  1  0.983  0.438  0.628  1.0
  O  O10  1  0.438  0.983  0.128  1.0
  O  O11  1  0.017  0.562  0.372  1.0
  O  O12  1  0.482  0.316  0.602  1.0
  O  O13  1  0.684  0.518  0.898  1.0
  O  O14  1  0.518  0.684  0.398  1.0
  O  O15  1  0.316  0.482  0.102  1.0
  O  O16  1  0.835  0.165  0.250  1.0
  O  O17  1  0.165  0.835  0.750  1.0
  O  O18  1  0.854  0.718  0.102  1.0
  O  O19  1  0.282  0.146  0.398  1.0
  O  O20  1  0.146  0.282  0.898  1.0
  O  O21  1  0.718  0.854  0.602  1.0
[/CIF]
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