Bi3(AsO5)2 crystallizes in the triclinic P-1 space group. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to one O(10), one O(2), one O(4), one O(5), and two equivalent O(1) atoms. In the second Bi site, Bi(2) is bonded to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted BiO6 pentagonal pyramids that share corners with two equivalent As(2)O4 tetrahedra and corners with three equivalent As(1)O4 tetrahedra. In the third Bi site, Bi(3) is bonded in a 8-coordinate geometry to one O(10), one O(2), one O(6), one O(8), two equivalent O(3), and two equivalent O(9) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form AsO4 tetrahedra that share corners with three equivalent Bi(2)O6 pentagonal pyramids. In the second As site, As(2) is bonded to one O(10), one O(7), one O(8), and one O(9) atom to form AsO4 tetrahedra that share corners with two equivalent Bi(2)O6 pentagonal pyramids. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 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 bent 120 degrees geometry to one Bi(1) and one Bi(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Bi(3) and one As(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Bi(1), one Bi(2), and one As(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Bi(1), one Bi(2), and one As(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Bi(2), one Bi(3), and one As(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Bi(2) and one As(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Bi(2), one Bi(3), and one As(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to two equivalent Bi(3) and one As(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Bi(1), one Bi(3), and one As(2) atom.
Bi3(AsO5)2 crystallizes in the triclinic P-1 space group. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to one O(10), one O(2), one O(4), one O(5), and two equivalent O(1) atoms. The Bi(1)-O(10) bond length is 2.66 Å. The Bi(1)-O(2) bond length is 2.23 Å. The Bi(1)-O(4) bond length is 2.84 Å. The Bi(1)-O(5) bond length is 2.39 Å. There is one shorter (2.21 Å) and one longer (2.28 Å) Bi(1)-O(1) bond length. In the second Bi site, Bi(2) is bonded to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted BiO6 pentagonal pyramids that share corners with two equivalent As(2)O4 tetrahedra and corners with three equivalent As(1)O4 tetrahedra. The Bi(2)-O(1) bond length is 2.26 Å. The Bi(2)-O(4) bond length is 2.43 Å. The Bi(2)-O(5) bond length is 2.62 Å. The Bi(2)-O(6) bond length is 2.49 Å. The Bi(2)-O(7) bond length is 2.24 Å. The Bi(2)-O(8) bond length is 2.36 Å. In the third Bi site, Bi(3) is bonded in a 8-coordinate geometry to one O(10), one O(2), one O(6), one O(8), two equivalent O(3), and two equivalent O(9) atoms. The Bi(3)-O(10) bond length is 2.42 Å. The Bi(3)-O(2) bond length is 2.27 Å. The Bi(3)-O(6) bond length is 2.73 Å. The Bi(3)-O(8) bond length is 2.85 Å. There is one shorter (2.39 Å) and one longer (2.49 Å) Bi(3)-O(3) bond length. There is one shorter (2.36 Å) and one longer (2.74 Å) Bi(3)-O(9) bond length. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form AsO4 tetrahedra that share corners with three equivalent Bi(2)O6 pentagonal pyramids. The As(1)-O(3) bond length is 1.74 Å. The As(1)-O(4) bond length is 1.73 Å. The As(1)-O(5) bond length is 1.73 Å. The As(1)-O(6) bond length is 1.71 Å. In the second As site, As(2) is bonded to one O(10), one O(7), one O(8), and one O(9) atom to form AsO4 tetrahedra that share corners with two equivalent Bi(2)O6 pentagonal pyramids. The As(2)-O(10) bond length is 1.71 Å. The As(2)-O(7) bond length is 1.73 Å. The As(2)-O(8) bond length is 1.73 Å. The As(2)-O(9) bond length is 1.74 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 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 bent 120 degrees geometry to one Bi(1) and one Bi(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Bi(3) and one As(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Bi(1), one Bi(2), and one As(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Bi(1), one Bi(2), and one As(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Bi(2), one Bi(3), and one As(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Bi(2) and one As(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Bi(2), one Bi(3), and one As(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to two equivalent Bi(3) and one As(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Bi(1), one Bi(3), and one As(2) atom.