The compound described by Ga4B2O9 crystallizes in the monoclinic Cm space group. There are six inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(1), one O(11), one O(12), one O(2), one O(5), and one O(6) atom to form GaO6 octahedra that share  a cornercorner with one Ga(3)O4 tetrahedra,  a cornercorner with one Ga(6)O4 tetrahedra,  a cornercorner with one B(4)O4 tetrahedra,  a cornercorner with one Ga(5)O5 trigonal bipyramid, edges with two equivalent Ga(1)O6 octahedra, and  an edgeedge with one Ga(2)O5 trigonal bipyramid. In the second Ga site, Ga(2) is bonded to one O(11), one O(13), one O(3), and two equivalent O(1) atoms to form GaO5 trigonal bipyramids that share corners with two equivalent Ga(4)O6 octahedra,  a cornercorner with one Ga(3)O4 tetrahedra,  a cornercorner with one Ga(6)O4 tetrahedra, edges with two equivalent Ga(1)O6 octahedra, and  an edgeedge with one Ga(5)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 48°. In the third Ga site, Ga(3) is bonded to one O(13), one O(4), and two equivalent O(2) atoms to form distorted GaO4 tetrahedra that share corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra, corners with two equivalent B(4)O4 tetrahedra,  a cornercorner with one Ga(2)O5 trigonal bipyramid, and  a cornercorner with one Ga(5)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 52-76°. In the fourth Ga site, Ga(4) is bonded to one O(10), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form GaO6 octahedra that share  a cornercorner with one Ga(3)O4 tetrahedra,  a cornercorner with one Ga(6)O4 tetrahedra,  a cornercorner with one B(4)O4 tetrahedra,  a cornercorner with one Ga(2)O5 trigonal bipyramid, edges with two equivalent Ga(4)O6 octahedra, and  an edgeedge with one Ga(5)O5 trigonal bipyramid. In the fifth Ga site, Ga(5) is bonded to one O(12), one O(13), one O(3), and two equivalent O(8) atoms to form GaO5 trigonal bipyramids that share corners with two equivalent Ga(1)O6 octahedra,  a cornercorner with one Ga(3)O4 tetrahedra, edges with two equivalent Ga(4)O6 octahedra, and  an edgeedge with one Ga(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 51°. In the sixth Ga site, Ga(6) is bonded to one O(11), one O(14), and two equivalent O(7) atoms to form GaO4 tetrahedra that share corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra,  a cornercorner with one B(4)O4 tetrahedra, and  a cornercorner with one Ga(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 70°. There are four inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(5) and two equivalent O(7) atoms. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(6) and two equivalent O(8) atoms. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(9) and two equivalent O(1) atoms. In the fourth B site, B(4) is bonded to one O(10), one O(14), and two equivalent O(2) atoms to form BO4 tetrahedra that share corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra,  a cornercorner with one Ga(6)O4 tetrahedra, and corners with two equivalent Ga(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-58°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ga(1), one Ga(2), and one B(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ga(1), one Ga(3), and one B(4) atom. In the third O site, O(3) is bonded in a trigonal pyramidal geometry to one Ga(2), one Ga(5), and two equivalent Ga(4) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ga(3) and two equivalent Ga(4) atoms. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to two equivalent Ga(1) and one B(1) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to two equivalent Ga(1) and one B(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Ga(4), one Ga(6), and one B(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Ga(4), one Ga(5), and one B(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to two equivalent Ga(4) and one B(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to two equivalent Ga(4) and one B(4) atom. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to one Ga(2), one Ga(6), and two equivalent Ga(1) atoms. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Ga(5) and two equivalent Ga(1) atoms. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ga(2), one Ga(3), and one Ga(5) atom. In the fourteenth O site, O(14) is bonded in a bent 120 degrees geometry to one Ga(6) and one B(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ga4B2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.114
_cell_length_b   8.114
_cell_length_c   10.845
_cell_angle_alpha   49.451
_cell_angle_beta   49.451
_cell_angle_gamma   41.548
_symmetry_Int_Tables_number   1
_cell_volume   340.379
_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
  Ga  Ga0  1  0.497  0.999  0.501  1.0
  Ga  Ga1  1  0.999  0.497  0.501  1.0
  Ga  Ga2  1  0.342  0.342  0.632  1.0
  Ga  Ga3  1  0.672  0.672  0.342  1.0
  Ga  Ga4  1  0.997  0.492  0.009  1.0
  Ga  Ga5  1  0.492  0.997  0.009  1.0
  Ga  Ga6  1  0.476  0.476  0.733  1.0
  Ga  Ga7  1  0.492  0.492  0.176  1.0
  B  B8  1  0.999  0.999  0.214  1.0
  B  B9  1  0.998  0.998  0.775  1.0
  B  B10  1  0.761  0.761  0.739  1.0
  B  B11  1  0.286  0.286  0.219  1.0
  O  O12  1  0.565  0.979  0.664  1.0
  O  O13  1  0.979  0.565  0.664  1.0
  O  O14  1  0.445  0.021  0.338  1.0
  O  O15  1  0.021  0.445  0.338  1.0
  O  O16  1  0.297  0.297  0.850  1.0
  O  O17  1  0.704  0.704  0.147  1.0
  O  O18  1  0.876  0.876  0.352  1.0
  O  O19  1  0.124  0.124  0.656  1.0
  O  O20  1  0.857  0.271  0.142  1.0
  O  O21  1  0.271  0.857  0.142  1.0
  O  O22  1  0.136  0.728  0.837  1.0
  O  O23  1  0.728  0.136  0.837  1.0
  O  O24  1  0.739  0.739  0.884  1.0
  O  O25  1  0.243  0.243  0.132  1.0
  O  O26  1  0.364  0.364  0.422  1.0
  O  O27  1  0.641  0.641  0.601  1.0
  O  O28  1  0.502  0.502  0.533  1.0
  O  O29  1  0.418  0.418  0.101  1.0
[/CIF]
.
The compound described by Ga4B2O9 crystallizes in the monoclinic Cm space group. There are six inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(1), one O(11), one O(12), one O(2), one O(5), and one O(6) atom to form GaO6 octahedra that share  a cornercorner with one Ga(3)O4 tetrahedra,  a cornercorner with one Ga(6)O4 tetrahedra,  a cornercorner with one B(4)O4 tetrahedra,  a cornercorner with one Ga(5)O5 trigonal bipyramid, edges with two equivalent Ga(1)O6 octahedra, and  an edgeedge with one Ga(2)O5 trigonal bipyramid. In the second Ga site, Ga(2) is bonded to one O(11), one O(13), one O(3), and two equivalent O(1) atoms to form GaO5 trigonal bipyramids that share corners with two equivalent Ga(4)O6 octahedra,  a cornercorner with one Ga(3)O4 tetrahedra,  a cornercorner with one Ga(6)O4 tetrahedra, edges with two equivalent Ga(1)O6 octahedra, and  an edgeedge with one Ga(5)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 48°. In the third Ga site, Ga(3) is bonded to one O(13), one O(4), and two equivalent O(2) atoms to form distorted GaO4 tetrahedra that share corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra, corners with two equivalent B(4)O4 tetrahedra,  a cornercorner with one Ga(2)O5 trigonal bipyramid, and  a cornercorner with one Ga(5)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 52-76°. In the fourth Ga site, Ga(4) is bonded to one O(10), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form GaO6 octahedra that share  a cornercorner with one Ga(3)O4 tetrahedra,  a cornercorner with one Ga(6)O4 tetrahedra,  a cornercorner with one B(4)O4 tetrahedra,  a cornercorner with one Ga(2)O5 trigonal bipyramid, edges with two equivalent Ga(4)O6 octahedra, and  an edgeedge with one Ga(5)O5 trigonal bipyramid. In the fifth Ga site, Ga(5) is bonded to one O(12), one O(13), one O(3), and two equivalent O(8) atoms to form GaO5 trigonal bipyramids that share corners with two equivalent Ga(1)O6 octahedra,  a cornercorner with one Ga(3)O4 tetrahedra, edges with two equivalent Ga(4)O6 octahedra, and  an edgeedge with one Ga(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 51°. In the sixth Ga site, Ga(6) is bonded to one O(11), one O(14), and two equivalent O(7) atoms to form GaO4 tetrahedra that share corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra,  a cornercorner with one B(4)O4 tetrahedra, and  a cornercorner with one Ga(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 70°. There are four inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(5) and two equivalent O(7) atoms. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(6) and two equivalent O(8) atoms. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(9) and two equivalent O(1) atoms. In the fourth B site, B(4) is bonded to one O(10), one O(14), and two equivalent O(2) atoms to form BO4 tetrahedra that share corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra,  a cornercorner with one Ga(6)O4 tetrahedra, and corners with two equivalent Ga(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-58°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ga(1), one Ga(2), and one B(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ga(1), one Ga(3), and one B(4) atom. In the third O site, O(3) is bonded in a trigonal pyramidal geometry to one Ga(2), one Ga(5), and two equivalent Ga(4) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ga(3) and two equivalent Ga(4) atoms. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to two equivalent Ga(1) and one B(1) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to two equivalent Ga(1) and one B(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Ga(4), one Ga(6), and one B(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Ga(4), one Ga(5), and one B(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to two equivalent Ga(4) and one B(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to two equivalent Ga(4) and one B(4) atom. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to one Ga(2), one Ga(6), and two equivalent Ga(1) atoms. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Ga(5) and two equivalent Ga(1) atoms. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ga(2), one Ga(3), and one Ga(5) atom. In the fourteenth O site, O(14) is bonded in a bent 120 degrees geometry to one Ga(6) and one B(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ga4B2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.114
_cell_length_b   8.114
_cell_length_c   10.845
_cell_angle_alpha   49.451
_cell_angle_beta   49.451
_cell_angle_gamma   41.548
_symmetry_Int_Tables_number   1
_cell_volume   340.379
_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
  Ga  Ga0  1  0.497  0.999  0.501  1.0
  Ga  Ga1  1  0.999  0.497  0.501  1.0
  Ga  Ga2  1  0.342  0.342  0.632  1.0
  Ga  Ga3  1  0.672  0.672  0.342  1.0
  Ga  Ga4  1  0.997  0.492  0.009  1.0
  Ga  Ga5  1  0.492  0.997  0.009  1.0
  Ga  Ga6  1  0.476  0.476  0.733  1.0
  Ga  Ga7  1  0.492  0.492  0.176  1.0
  B  B8  1  0.999  0.999  0.214  1.0
  B  B9  1  0.998  0.998  0.775  1.0
  B  B10  1  0.761  0.761  0.739  1.0
  B  B11  1  0.286  0.286  0.219  1.0
  O  O12  1  0.565  0.979  0.664  1.0
  O  O13  1  0.979  0.565  0.664  1.0
  O  O14  1  0.445  0.021  0.338  1.0
  O  O15  1  0.021  0.445  0.338  1.0
  O  O16  1  0.297  0.297  0.850  1.0
  O  O17  1  0.704  0.704  0.147  1.0
  O  O18  1  0.876  0.876  0.352  1.0
  O  O19  1  0.124  0.124  0.656  1.0
  O  O20  1  0.857  0.271  0.142  1.0
  O  O21  1  0.271  0.857  0.142  1.0
  O  O22  1  0.136  0.728  0.837  1.0
  O  O23  1  0.728  0.136  0.837  1.0
  O  O24  1  0.739  0.739  0.884  1.0
  O  O25  1  0.243  0.243  0.132  1.0
  O  O26  1  0.364  0.364  0.422  1.0
  O  O27  1  0.641  0.641  0.601  1.0
  O  O28  1  0.502  0.502  0.533  1.0
  O  O29  1  0.418  0.418  0.101  1.0
[/CIF]
.