Bi2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(2), one O(9), two equivalent O(1), and two equivalent O(10) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 3-32°. In the second Bi site, Bi(2) is bonded to one O(1), one O(8), two equivalent O(2), and two equivalent O(7) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 3-32°. In the third Bi site, Bi(3) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 4-32°. In the fourth Bi site, Bi(4) is bonded to one O(3), one O(9), two equivalent O(4), and two equivalent O(5) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 4-32°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2) and two equivalent Bi(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Bi(1) and two equivalent Bi(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Bi(4) and two equivalent Bi(3) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3) and two equivalent Bi(4) atoms. In the fifth O site, O(5) is bonded in a linear geometry to two equivalent Bi(4) atoms. In the sixth O site, O(6) is bonded in a linear geometry to two equivalent Bi(3) atoms. In the seventh O site, O(7) is bonded in a linear geometry to two equivalent Bi(2) atoms. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Bi(2) and one Bi(3) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Bi(1) and one Bi(4) atom. In the tenth O site, O(10) is bonded in a linear geometry to two equivalent Bi(1) atoms.
Bi2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(2), one O(9), two equivalent O(1), and two equivalent O(10) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 3-32°. The Bi(1)-O(2) bond length is 2.24 Å. The Bi(1)-O(9) bond length is 2.11 Å. Both Bi(1)-O(1) bond lengths are 2.21 Å. There is one shorter (2.06 Å) and one longer (2.11 Å) Bi(1)-O(10) bond length. In the second Bi site, Bi(2) is bonded to one O(1), one O(8), two equivalent O(2), and two equivalent O(7) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 3-32°. The Bi(2)-O(1) bond length is 2.24 Å. The Bi(2)-O(8) bond length is 2.11 Å. Both Bi(2)-O(2) bond lengths are 2.21 Å. There is one shorter (2.06 Å) and one longer (2.11 Å) Bi(2)-O(7) bond length. In the third Bi site, Bi(3) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 4-32°. The Bi(3)-O(4) bond length is 2.24 Å. The Bi(3)-O(8) bond length is 2.11 Å. Both Bi(3)-O(3) bond lengths are 2.21 Å. There is one shorter (2.06 Å) and one longer (2.11 Å) Bi(3)-O(6) bond length. In the fourth Bi site, Bi(4) is bonded to one O(3), one O(9), two equivalent O(4), and two equivalent O(5) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 4-32°. The Bi(4)-O(3) bond length is 2.24 Å. The Bi(4)-O(9) bond length is 2.11 Å. Both Bi(4)-O(4) bond lengths are 2.21 Å. There is one shorter (2.06 Å) and one longer (2.11 Å) Bi(4)-O(5) bond length. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Bi(2) and two equivalent Bi(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Bi(1) and two equivalent Bi(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Bi(4) and two equivalent Bi(3) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3) and two equivalent Bi(4) atoms. In the fifth O site, O(5) is bonded in a linear geometry to two equivalent Bi(4) atoms. In the sixth O site, O(6) is bonded in a linear geometry to two equivalent Bi(3) atoms. In the seventh O site, O(7) is bonded in a linear geometry to two equivalent Bi(2) atoms. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Bi(2) and one Bi(3) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Bi(1) and one Bi(4) atom. In the tenth O site, O(10) is bonded in a linear geometry to two equivalent Bi(1) atoms.