The crystal structure described by Ba3GeO5 crystallizes in the trigonal R3m space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(6), one O(7), one O(8), one O(9), and two equivalent O(3) atoms to form distorted BaO6 pentagonal pyramids that share  a cornercorner with one Ba(3)O6 octahedra, corners with two equivalent Ba(1)O6 pentagonal pyramids,  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, faces with two equivalent Ba(3)O6 octahedra, and faces with two equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 7°. In the second Ba site, Ba(2) is bonded in a distorted hexagonal planar geometry to one O(2), one O(4), one O(5), one O(9), and two equivalent O(1) atoms. In the third Ba site, Ba(3) is bonded to one O(1), one O(2), one O(3), one O(8), and two equivalent O(7) atoms to form distorted BaO6 octahedra that share corners with two equivalent Ba(3)O6 octahedra,  a cornercorner with one Ba(1)O6 pentagonal pyramid,  a cornercorner with one Ge(2)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with two equivalent Ge(1)O4 tetrahedra, edges with two equivalent Ba(3)O6 octahedra, and faces with two equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 81°. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(4) and three equivalent O(7) atoms to form GeO4 tetrahedra that share corners with six equivalent Ba(3)O6 octahedra and corners with three equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 54°. In the second Ge site, Ge(2) is bonded to one O(5) and three equivalent O(3) atoms to form GeO4 tetrahedra that share corners with three equivalent Ba(3)O6 octahedra and corners with six equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 57°. In the third Ge site, Ge(3) is bonded to one O(6) and three equivalent O(1) atoms to form GeO4 tetrahedra that share corners with three equivalent Ba(3)O6 octahedra and corners with three equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 59°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Ba(3), two equivalent Ba(2), and one Ge(3) atom. In the second O site, O(2) is bonded to three equivalent Ba(2) and three equivalent Ba(3) atoms to form a mixture of face and corner-sharing OBa6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Ba(3), two equivalent Ba(1), and one Ge(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to three equivalent Ba(2) and one Ge(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to three equivalent Ba(2) and one Ge(2) atom. In the sixth O site, O(6) is bonded to three equivalent Ba(1) and one Ge(3) atom to form distorted corner-sharing OBa3Ge tetrahedra. The corner-sharing octahedral tilt angles range from 11-65°. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Ba(1), two equivalent Ba(3), and one Ge(1) atom. In the eighth O site, O(8) is bonded to three equivalent Ba(1) and three equivalent Ba(3) atoms to form OBa6 octahedra that share corners with three equivalent O(2)Ba6 octahedra, corners with three equivalent O(6)Ba3Ge tetrahedra, and  a faceface with one O(9)Ba6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the ninth O site, O(9) is bonded to three equivalent Ba(1) and three equivalent Ba(2) atoms to form OBa6 octahedra that share corners with three equivalent O(6)Ba3Ge tetrahedra,  a faceface with one O(2)Ba6 octahedra, and  a faceface with one O(8)Ba6 octahedra. is represented by the CIF card [CIF]
data_Ba3GeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.715
_cell_length_b   10.715
_cell_length_c   10.715
_cell_angle_alpha   44.248
_cell_angle_beta   44.248
_cell_angle_gamma   44.248
_symmetry_Int_Tables_number   1
_cell_volume   544.273
_cell_formula_units_Z   3
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
  Ba  Ba0  1  0.286  0.755  0.286  1.0
  Ba  Ba1  1  0.718  0.718  0.234  1.0
  Ba  Ba2  1  0.755  0.286  0.286  1.0
  Ba  Ba3  1  0.010  0.497  0.497  1.0
  Ba  Ba4  1  0.234  0.718  0.718  1.0
  Ba  Ba5  1  0.286  0.286  0.755  1.0
  Ba  Ba6  1  0.718  0.234  0.718  1.0
  Ba  Ba7  1  0.497  0.010  0.497  1.0
  Ba  Ba8  1  0.497  0.497  0.010  1.0
  Ge  Ge9  1  0.999  0.999  0.999  1.0
  Ge  Ge10  1  0.781  0.781  0.781  1.0
  Ge  Ge11  1  0.215  0.215  0.215  1.0
  O  O12  1  0.356  0.995  0.356  1.0
  O  O13  1  0.623  0.623  0.623  1.0
  O  O14  1  0.640  0.003  0.640  1.0
  O  O15  1  0.640  0.640  0.003  1.0
  O  O16  1  0.938  0.938  0.938  1.0
  O  O17  1  0.842  0.842  0.842  1.0
  O  O18  1  0.995  0.356  0.356  1.0
  O  O19  1  0.003  0.640  0.640  1.0
  O  O20  1  0.153  0.153  0.153  1.0
  O  O21  1  0.140  0.775  0.140  1.0
  O  O22  1  0.140  0.140  0.775  1.0
  O  O23  1  0.356  0.356  0.995  1.0
  O  O24  1  0.383  0.383  0.383  1.0
  O  O25  1  0.500  0.500  0.500  1.0
  O  O26  1  0.775  0.140  0.140  1.0
[/CIF]
.
The crystal structure described by Ba3GeO5 crystallizes in the trigonal R3m space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(6), one O(7), one O(8), one O(9), and two equivalent O(3) atoms to form distorted BaO6 pentagonal pyramids that share  a cornercorner with one Ba(3)O6 octahedra, corners with two equivalent Ba(1)O6 pentagonal pyramids,  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, faces with two equivalent Ba(3)O6 octahedra, and faces with two equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 7°. In the second Ba site, Ba(2) is bonded in a distorted hexagonal planar geometry to one O(2), one O(4), one O(5), one O(9), and two equivalent O(1) atoms. In the third Ba site, Ba(3) is bonded to one O(1), one O(2), one O(3), one O(8), and two equivalent O(7) atoms to form distorted BaO6 octahedra that share corners with two equivalent Ba(3)O6 octahedra,  a cornercorner with one Ba(1)O6 pentagonal pyramid,  a cornercorner with one Ge(2)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with two equivalent Ge(1)O4 tetrahedra, edges with two equivalent Ba(3)O6 octahedra, and faces with two equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 81°. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(4) and three equivalent O(7) atoms to form GeO4 tetrahedra that share corners with six equivalent Ba(3)O6 octahedra and corners with three equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 54°. In the second Ge site, Ge(2) is bonded to one O(5) and three equivalent O(3) atoms to form GeO4 tetrahedra that share corners with three equivalent Ba(3)O6 octahedra and corners with six equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 57°. In the third Ge site, Ge(3) is bonded to one O(6) and three equivalent O(1) atoms to form GeO4 tetrahedra that share corners with three equivalent Ba(3)O6 octahedra and corners with three equivalent Ba(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 59°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Ba(3), two equivalent Ba(2), and one Ge(3) atom. In the second O site, O(2) is bonded to three equivalent Ba(2) and three equivalent Ba(3) atoms to form a mixture of face and corner-sharing OBa6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Ba(3), two equivalent Ba(1), and one Ge(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to three equivalent Ba(2) and one Ge(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to three equivalent Ba(2) and one Ge(2) atom. In the sixth O site, O(6) is bonded to three equivalent Ba(1) and one Ge(3) atom to form distorted corner-sharing OBa3Ge tetrahedra. The corner-sharing octahedral tilt angles range from 11-65°. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Ba(1), two equivalent Ba(3), and one Ge(1) atom. In the eighth O site, O(8) is bonded to three equivalent Ba(1) and three equivalent Ba(3) atoms to form OBa6 octahedra that share corners with three equivalent O(2)Ba6 octahedra, corners with three equivalent O(6)Ba3Ge tetrahedra, and  a faceface with one O(9)Ba6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the ninth O site, O(9) is bonded to three equivalent Ba(1) and three equivalent Ba(2) atoms to form OBa6 octahedra that share corners with three equivalent O(6)Ba3Ge tetrahedra,  a faceface with one O(2)Ba6 octahedra, and  a faceface with one O(8)Ba6 octahedra. is represented by the CIF card [CIF]
data_Ba3GeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.715
_cell_length_b   10.715
_cell_length_c   10.715
_cell_angle_alpha   44.248
_cell_angle_beta   44.248
_cell_angle_gamma   44.248
_symmetry_Int_Tables_number   1
_cell_volume   544.273
_cell_formula_units_Z   3
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
  Ba  Ba0  1  0.286  0.755  0.286  1.0
  Ba  Ba1  1  0.718  0.718  0.234  1.0
  Ba  Ba2  1  0.755  0.286  0.286  1.0
  Ba  Ba3  1  0.010  0.497  0.497  1.0
  Ba  Ba4  1  0.234  0.718  0.718  1.0
  Ba  Ba5  1  0.286  0.286  0.755  1.0
  Ba  Ba6  1  0.718  0.234  0.718  1.0
  Ba  Ba7  1  0.497  0.010  0.497  1.0
  Ba  Ba8  1  0.497  0.497  0.010  1.0
  Ge  Ge9  1  0.999  0.999  0.999  1.0
  Ge  Ge10  1  0.781  0.781  0.781  1.0
  Ge  Ge11  1  0.215  0.215  0.215  1.0
  O  O12  1  0.356  0.995  0.356  1.0
  O  O13  1  0.623  0.623  0.623  1.0
  O  O14  1  0.640  0.003  0.640  1.0
  O  O15  1  0.640  0.640  0.003  1.0
  O  O16  1  0.938  0.938  0.938  1.0
  O  O17  1  0.842  0.842  0.842  1.0
  O  O18  1  0.995  0.356  0.356  1.0
  O  O19  1  0.003  0.640  0.640  1.0
  O  O20  1  0.153  0.153  0.153  1.0
  O  O21  1  0.140  0.775  0.140  1.0
  O  O22  1  0.140  0.140  0.775  1.0
  O  O23  1  0.356  0.356  0.995  1.0
  O  O24  1  0.383  0.383  0.383  1.0
  O  O25  1  0.500  0.500  0.500  1.0
  O  O26  1  0.775  0.140  0.140  1.0
[/CIF]
.