B4SnO7 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent B sites. In the first B site, B(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing BO4 tetrahedra. In the second B site, B(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form corner-sharing BO4 tetrahedra. Sn(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent B(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one B(1) and two equivalent B(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one B(1), one B(2), and one Sn(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one B(1), one B(2), and one Sn(1) atom.
B4SnO7 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent B sites. In the first B site, B(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing BO4 tetrahedra. The B(1)-O(1) bond length is 1.47 Å. The B(1)-O(2) bond length is 1.56 Å. The B(1)-O(3) bond length is 1.45 Å. The B(1)-O(4) bond length is 1.43 Å. In the second B site, B(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form corner-sharing BO4 tetrahedra. The B(2)-O(3) bond length is 1.44 Å. The B(2)-O(4) bond length is 1.41 Å. There is one shorter (1.53 Å) and one longer (1.55 Å) B(2)-O(2) bond length. Sn(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(4) atoms. The Sn(1)-O(1) bond length is 2.29 Å. Both Sn(1)-O(3) bond lengths are 2.37 Å. Both Sn(1)-O(4) bond lengths are 2.63 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent B(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one B(1) and two equivalent B(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one B(1), one B(2), and one Sn(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one B(1), one B(2), and one Sn(1) atom.