PbBi6As4O20 crystallizes in the triclinic P-1 space group. Pb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(10), and two equivalent O(9) atoms. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 5-coordinate geometry to one O(5), one O(6), one O(8), and two equivalent O(4) atoms. In the second Bi site, Bi(2) is bonded in a 8-coordinate geometry to one O(10), one O(2), one O(4), one O(5), one O(6), one O(9), and two equivalent O(3) atoms. In the third Bi site, Bi(3) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(7) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded in a tetrahedral geometry to one O(2), one O(6), one O(8), and one O(9) atom. In the second As site, As(2) is bonded in a tetrahedral geometry to one O(1), one O(10), one O(5), and one O(7) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Pb(1), one Bi(3), and one As(2) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Bi(2), one Bi(3), and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3) and two equivalent Bi(2) atoms. In the fourth O site, O(4) is bonded to one Bi(2), one Bi(3), and two equivalent Bi(1) atoms to form distorted edge-sharing OBi4 tetrahedra. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Bi(1), one Bi(2), and one As(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Bi(1), one Bi(2), and one As(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Bi(3) and one As(2) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Bi(1) and one As(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Pb(1), one Bi(2), and one As(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Pb(1), one Bi(2), and one As(2) atom.
PbBi6As4O20 crystallizes in the triclinic P-1 space group. Pb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(10), and two equivalent O(9) atoms. Both Pb(1)-O(1) bond lengths are 2.68 Å. Both Pb(1)-O(10) bond lengths are 2.70 Å. Both Pb(1)-O(9) bond lengths are 2.54 Å. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 5-coordinate geometry to one O(5), one O(6), one O(8), and two equivalent O(4) atoms. The Bi(1)-O(5) bond length is 2.37 Å. The Bi(1)-O(6) bond length is 2.44 Å. The Bi(1)-O(8) bond length is 2.44 Å. There is one shorter (2.20 Å) and one longer (2.36 Å) Bi(1)-O(4) bond length. In the second Bi site, Bi(2) is bonded in a 8-coordinate geometry to one O(10), one O(2), one O(4), one O(5), one O(6), one O(9), and two equivalent O(3) atoms. The Bi(2)-O(10) bond length is 2.41 Å. The Bi(2)-O(2) bond length is 2.78 Å. The Bi(2)-O(4) bond length is 2.62 Å. The Bi(2)-O(5) bond length is 2.80 Å. The Bi(2)-O(6) bond length is 2.66 Å. The Bi(2)-O(9) bond length is 2.42 Å. There is one shorter (2.26 Å) and one longer (2.38 Å) Bi(2)-O(3) bond length. In the third Bi site, Bi(3) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(7) atom. The Bi(3)-O(1) bond length is 2.46 Å. The Bi(3)-O(2) bond length is 2.39 Å. The Bi(3)-O(3) bond length is 2.15 Å. The Bi(3)-O(4) bond length is 2.35 Å. The Bi(3)-O(7) bond length is 2.30 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a tetrahedral geometry to one O(2), one O(6), one O(8), and one O(9) atom. The As(1)-O(2) bond length is 1.72 Å. The As(1)-O(6) bond length is 1.74 Å. The As(1)-O(8) bond length is 1.73 Å. The As(1)-O(9) bond length is 1.73 Å. In the second As site, As(2) is bonded in a tetrahedral geometry to one O(1), one O(10), one O(5), and one O(7) atom. The As(2)-O(1) bond length is 1.73 Å. The As(2)-O(10) bond length is 1.72 Å. The As(2)-O(5) bond length is 1.72 Å. The As(2)-O(7) bond length is 1.73 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Pb(1), one Bi(3), and one As(2) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Bi(2), one Bi(3), and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Bi(3) and two equivalent Bi(2) atoms. In the fourth O site, O(4) is bonded to one Bi(2), one Bi(3), and two equivalent Bi(1) atoms to form distorted edge-sharing OBi4 tetrahedra. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Bi(1), one Bi(2), and one As(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Bi(1), one Bi(2), and one As(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Bi(3) and one As(2) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Bi(1) and one As(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Pb(1), one Bi(2), and one As(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Pb(1), one Bi(2), and one As(2) atom.