Li2B4O7 crystallizes in the tetragonal I4_1cd space group. Li(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Li(1), one B(1), and one B(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(1), one B(1), and one B(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Li(1) and one B(1) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to two equivalent B(2) atoms.
Li2B4O7 crystallizes in the tetragonal I4_1cd space group. Li(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. The Li(1)-O(1) bond length is 2.41 Å. The Li(1)-O(2) bond length is 2.17 Å. There is one shorter (1.89 Å) and one longer (1.94 Å) Li(1)-O(3) bond length. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The B(1)-O(1) bond length is 1.47 Å. The B(1)-O(2) bond length is 1.48 Å. The B(1)-O(3) bond length is 1.30 Å. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(4) atom. The B(2)-O(1) bond length is 1.38 Å. The B(2)-O(2) bond length is 1.38 Å. The B(2)-O(4) bond length is 1.41 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Li(1), one B(1), and one B(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(1), one B(1), and one B(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Li(1) and one B(1) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to two equivalent B(2) atoms.