Bi2Fe2Ga2O9 crystallizes in the orthorhombic Pbam space group. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Ga(1)O4 tetrahedra and edges with two equivalent Fe(1)O6 octahedra. Ga(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form GaO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra and  a cornercorner with one Ga(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-60°. Bi(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one Ga(1), and one Bi(1) atom. In the second O site, O(2) is bonded to two equivalent Fe(1) and two equivalent Bi(1) atoms to form a mixture of distorted edge and corner-sharing OFe2Bi2 tetrahedra. In the third O site, O(3) is bonded in a linear geometry to two equivalent Ga(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one Ga(1) atom.
Bi2Fe2Ga2O9 crystallizes in the orthorhombic Pbam space group. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Ga(1)O4 tetrahedra and edges with two equivalent Fe(1)O6 octahedra. Both Fe(1)-O(1) bond lengths are 1.99 Å. Both Fe(1)-O(2) bond lengths are 2.00 Å. Both Fe(1)-O(4) bond lengths are 1.94 Å. Ga(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form GaO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra and  a cornercorner with one Ga(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-60°. The Ga(1)-O(3) bond length is 1.83 Å. The Ga(1)-O(4) bond length is 1.87 Å. Both Ga(1)-O(1) bond lengths are 1.89 Å. Bi(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. Both Bi(1)-O(1) bond lengths are 2.19 Å. There is one shorter (2.21 Å) and one longer (2.45 Å) Bi(1)-O(2) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one Ga(1), and one Bi(1) atom. In the second O site, O(2) is bonded to two equivalent Fe(1) and two equivalent Bi(1) atoms to form a mixture of distorted edge and corner-sharing OFe2Bi2 tetrahedra. In the third O site, O(3) is bonded in a linear geometry to two equivalent Ga(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one Ga(1) atom.