Bi3(B3O7)2 crystallizes in the triclinic P1 space group. There are six inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(1), one O(4), and one O(9) atom. In the second B site, B(2) is bonded to one O(10), one O(2), one O(6), and one O(7) atom to form corner-sharing BO4 tetrahedra. In the third B site, B(3) is bonded to one O(11), one O(3), one O(5), and one O(8) atom to form corner-sharing BO4 tetrahedra. In the fourth B site, B(4) is bonded to one O(13), one O(14), one O(6), and one O(9) atom to form corner-sharing BO4 tetrahedra. In the fifth B site, B(5) is bonded to one O(11), one O(12), one O(14), and one O(4) atom to form corner-sharing BO4 tetrahedra. In the sixth B site, B(6) is bonded to one O(10), one O(12), one O(13), and one O(5) atom to form corner-sharing BO4 tetrahedra. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(12), one O(3), one O(4), one O(5), one O(7), and one O(9) atom. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to one O(13), one O(2), one O(3), one O(5), one O(6), and one O(9) atom. In the third Bi site, Bi(3) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(14), one O(2), one O(4), one O(7), and one O(8) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one B(1), one Bi(1), and one Bi(3) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one B(2), one Bi(2), and one Bi(3) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one B(3), one Bi(1), and one Bi(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one B(1), one B(5), one Bi(1), and one Bi(3) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one B(3), one B(6), one Bi(1), and one Bi(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one B(2), one B(4), and one Bi(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one B(2), one Bi(1), and one Bi(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one B(3) and one Bi(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one B(1), one B(4), one Bi(1), and one Bi(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one B(2), one B(6), one Bi(1), and one Bi(3) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one B(3), one B(5), and one Bi(3) atom. In the twelfth O site, O(12) is bonded in a distorted bent 120 degrees geometry to one B(5), one B(6), and one Bi(1) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 120 degrees geometry to one B(4), one B(6), and one Bi(2) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one B(4), one B(5), and one Bi(3) atom.
Bi3(B3O7)2 crystallizes in the triclinic P1 space group. There are six inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(1), one O(4), and one O(9) atom. The B(1)-O(1) bond length is 1.35 Å. The B(1)-O(4) bond length is 1.41 Å. The B(1)-O(9) bond length is 1.39 Å. In the second B site, B(2) is bonded to one O(10), one O(2), one O(6), and one O(7) atom to form corner-sharing BO4 tetrahedra. The B(2)-O(10) bond length is 1.56 Å. The B(2)-O(2) bond length is 1.45 Å. The B(2)-O(6) bond length is 1.48 Å. The B(2)-O(7) bond length is 1.46 Å. In the third B site, B(3) is bonded to one O(11), one O(3), one O(5), and one O(8) atom to form corner-sharing BO4 tetrahedra. The B(3)-O(11) bond length is 1.50 Å. The B(3)-O(3) bond length is 1.49 Å. The B(3)-O(5) bond length is 1.53 Å. The B(3)-O(8) bond length is 1.44 Å. In the fourth B site, B(4) is bonded to one O(13), one O(14), one O(6), and one O(9) atom to form corner-sharing BO4 tetrahedra. The B(4)-O(13) bond length is 1.44 Å. The B(4)-O(14) bond length is 1.45 Å. The B(4)-O(6) bond length is 1.45 Å. The B(4)-O(9) bond length is 1.62 Å. In the fifth B site, B(5) is bonded to one O(11), one O(12), one O(14), and one O(4) atom to form corner-sharing BO4 tetrahedra. The B(5)-O(11) bond length is 1.46 Å. The B(5)-O(12) bond length is 1.45 Å. The B(5)-O(14) bond length is 1.47 Å. The B(5)-O(4) bond length is 1.52 Å. In the sixth B site, B(6) is bonded to one O(10), one O(12), one O(13), and one O(5) atom to form corner-sharing BO4 tetrahedra. The B(6)-O(10) bond length is 1.51 Å. The B(6)-O(12) bond length is 1.45 Å. The B(6)-O(13) bond length is 1.45 Å. The B(6)-O(5) bond length is 1.49 Å. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(12), one O(3), one O(4), one O(5), one O(7), and one O(9) atom. The Bi(1)-O(1) bond length is 2.26 Å. The Bi(1)-O(10) bond length is 2.49 Å. The Bi(1)-O(12) bond length is 2.51 Å. The Bi(1)-O(3) bond length is 2.33 Å. The Bi(1)-O(4) bond length is 2.64 Å. The Bi(1)-O(5) bond length is 2.49 Å. The Bi(1)-O(7) bond length is 2.56 Å. The Bi(1)-O(9) bond length is 2.90 Å. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to one O(13), one O(2), one O(3), one O(5), one O(6), and one O(9) atom. The Bi(2)-O(13) bond length is 2.44 Å. The Bi(2)-O(2) bond length is 2.18 Å. The Bi(2)-O(3) bond length is 2.23 Å. The Bi(2)-O(5) bond length is 2.61 Å. The Bi(2)-O(6) bond length is 2.60 Å. The Bi(2)-O(9) bond length is 2.52 Å. In the third Bi site, Bi(3) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(14), one O(2), one O(4), one O(7), and one O(8) atom. The Bi(3)-O(1) bond length is 2.67 Å. The Bi(3)-O(10) bond length is 2.53 Å. The Bi(3)-O(11) bond length is 2.75 Å. The Bi(3)-O(14) bond length is 2.51 Å. The Bi(3)-O(2) bond length is 2.80 Å. The Bi(3)-O(4) bond length is 2.51 Å. The Bi(3)-O(7) bond length is 2.33 Å. The Bi(3)-O(8) bond length is 2.20 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one B(1), one Bi(1), and one Bi(3) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one B(2), one Bi(2), and one Bi(3) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one B(3), one Bi(1), and one Bi(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one B(1), one B(5), one Bi(1), and one Bi(3) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one B(3), one B(6), one Bi(1), and one Bi(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one B(2), one B(4), and one Bi(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one B(2), one Bi(1), and one Bi(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one B(3) and one Bi(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one B(1), one B(4), one Bi(1), and one Bi(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one B(2), one B(6), one Bi(1), and one Bi(3) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one B(3), one B(5), and one Bi(3) atom. In the twelfth O site, O(12) is bonded in a distorted bent 120 degrees geometry to one B(5), one B(6), and one Bi(1) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 120 degrees geometry to one B(4), one B(6), and one Bi(2) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one B(4), one B(5), and one Bi(3) atom.