The crystal structure described by Cs3AlGe2O7 crystallizes in the monoclinic C2/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(4), three equivalent O(2), and three equivalent O(3) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(3) atoms. Al(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Ge(1)O4 tetrahedra. 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 two equivalent Al(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted bent 120 degrees geometry to four equivalent Cs(1) and two equivalent Ge(1) atoms. In the second O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cs(1), two equivalent Cs(2), one Al(1), and one Ge(1) atom. In the third O site, O(2) is bonded in a distorted bent 120 degrees geometry to three equivalent Cs(1), one Al(1), and one Ge(1) atom. In the fourth O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cs(2), three equivalent Cs(1), and one Ge(1) atom. is represented by the CIF card [CIF]
data_Cs3AlGe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.898
_cell_length_b   9.898
_cell_length_c   7.658
_cell_angle_alpha   73.057
_cell_angle_beta   73.057
_cell_angle_gamma   121.534
_symmetry_Int_Tables_number   1
_cell_volume   513.114
_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
  Cs  Cs0  1  0.591  0.983  0.731  1.0
  Cs  Cs1  1  0.012  0.988  0.750  1.0
  Cs  Cs2  1  0.983  0.591  0.231  1.0
  Cs  Cs3  1  0.988  0.012  0.250  1.0
  Cs  Cs4  1  0.017  0.409  0.769  1.0
  Cs  Cs5  1  0.409  0.017  0.269  1.0
  Al  Al6  1  0.442  0.558  0.750  1.0
  Al  Al7  1  0.558  0.442  0.250  1.0
  Ge  Ge8  1  0.762  0.563  0.761  1.0
  Ge  Ge9  1  0.437  0.238  0.739  1.0
  Ge  Ge10  1  0.563  0.762  0.261  1.0
  Ge  Ge11  1  0.238  0.437  0.239  1.0
  O  O12  1  0.656  0.660  0.734  1.0
  O  O13  1  0.660  0.656  0.234  1.0
  O  O14  1  0.521  0.278  0.475  1.0
  O  O15  1  0.340  0.344  0.766  1.0
  O  O16  1  0.003  0.276  0.439  1.0
  O  O17  1  0.479  0.722  0.525  1.0
  O  O18  1  0.276  0.003  0.939  1.0
  O  O19  1  0.278  0.521  0.975  1.0
  O  O20  1  0.355  0.645  0.250  1.0
  O  O21  1  0.344  0.340  0.266  1.0
  O  O22  1  0.724  0.997  0.061  1.0
  O  O23  1  0.645  0.355  0.750  1.0
  O  O24  1  0.997  0.724  0.561  1.0
  O  O25  1  0.722  0.479  0.025  1.0
[/CIF]
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The crystal structure described by Cs3AlGe2O7 crystallizes in the monoclinic C2/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(4), three equivalent O(2), and three equivalent O(3) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(3) atoms. Al(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Ge(1)O4 tetrahedra. 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 two equivalent Al(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted bent 120 degrees geometry to four equivalent Cs(1) and two equivalent Ge(1) atoms. In the second O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cs(1), two equivalent Cs(2), one Al(1), and one Ge(1) atom. In the third O site, O(2) is bonded in a distorted bent 120 degrees geometry to three equivalent Cs(1), one Al(1), and one Ge(1) atom. In the fourth O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cs(2), three equivalent Cs(1), and one Ge(1) atom. is represented by the CIF card [CIF]
data_Cs3AlGe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.898
_cell_length_b   9.898
_cell_length_c   7.658
_cell_angle_alpha   73.057
_cell_angle_beta   73.057
_cell_angle_gamma   121.534
_symmetry_Int_Tables_number   1
_cell_volume   513.114
_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
  Cs  Cs0  1  0.591  0.983  0.731  1.0
  Cs  Cs1  1  0.012  0.988  0.750  1.0
  Cs  Cs2  1  0.983  0.591  0.231  1.0
  Cs  Cs3  1  0.988  0.012  0.250  1.0
  Cs  Cs4  1  0.017  0.409  0.769  1.0
  Cs  Cs5  1  0.409  0.017  0.269  1.0
  Al  Al6  1  0.442  0.558  0.750  1.0
  Al  Al7  1  0.558  0.442  0.250  1.0
  Ge  Ge8  1  0.762  0.563  0.761  1.0
  Ge  Ge9  1  0.437  0.238  0.739  1.0
  Ge  Ge10  1  0.563  0.762  0.261  1.0
  Ge  Ge11  1  0.238  0.437  0.239  1.0
  O  O12  1  0.656  0.660  0.734  1.0
  O  O13  1  0.660  0.656  0.234  1.0
  O  O14  1  0.521  0.278  0.475  1.0
  O  O15  1  0.340  0.344  0.766  1.0
  O  O16  1  0.003  0.276  0.439  1.0
  O  O17  1  0.479  0.722  0.525  1.0
  O  O18  1  0.276  0.003  0.939  1.0
  O  O19  1  0.278  0.521  0.975  1.0
  O  O20  1  0.355  0.645  0.250  1.0
  O  O21  1  0.344  0.340  0.266  1.0
  O  O22  1  0.724  0.997  0.061  1.0
  O  O23  1  0.645  0.355  0.750  1.0
  O  O24  1  0.997  0.724  0.561  1.0
  O  O25  1  0.722  0.479  0.025  1.0
[/CIF]
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