Li7B18O crystallizes in the monoclinic P2/m space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded in a single-bond geometry to two equivalent B(4), two equivalent B(6), two equivalent B(9), and one O(1) atom. In the second Li site, Li(2) is bonded in a 18-coordinate geometry to two equivalent B(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), two equivalent B(5), two equivalent B(6), two equivalent B(7), two equivalent B(8), and two equivalent B(9) atoms. In the third Li site, Li(3) is bonded in a linear geometry to two equivalent O(1) atoms. In the fourth Li site, Li(4) is bonded in a single-bond geometry to two equivalent B(3), two equivalent B(5), two equivalent B(7), and one O(1) atom. There are nine inequivalent B sites. In the first B site, B(1) is bonded in a 7-coordinate geometry to two equivalent Li(2), one B(1), two equivalent B(2), and two equivalent B(4) atoms. In the second B site, B(2) is bonded in a 5-coordinate geometry to two equivalent Li(2), one B(3), two equivalent B(1), and two equivalent B(4) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Li(2), two equivalent Li(4), one B(2), two equivalent B(5), and two equivalent B(7) atoms. In the fourth B site, B(4) is bonded in a 9-coordinate geometry to two equivalent Li(1), two equivalent Li(2), one B(6), two equivalent B(1), and two equivalent B(2) atoms. In the fifth B site, B(5) is bonded in a 9-coordinate geometry to two equivalent Li(2), two equivalent Li(4), one B(5), two equivalent B(3), and two equivalent B(7) atoms. In the sixth B site, B(6) is bonded in a 9-coordinate geometry to two equivalent Li(1), two equivalent Li(2), one B(4), two equivalent B(8), and two equivalent B(9) atoms. In the seventh B site, B(7) is bonded in a 9-coordinate geometry to two equivalent Li(2), two equivalent Li(4), one B(8), two equivalent B(3), and two equivalent B(5) atoms. In the eighth B site, B(8) is bonded in a 7-coordinate geometry to two equivalent Li(2), one B(7), two equivalent B(6), and two equivalent B(9) atoms. In the ninth B site, B(9) is bonded in a 9-coordinate geometry to two equivalent Li(1), two equivalent Li(2), one B(9), two equivalent B(6), and two equivalent B(8) atoms. O(1) is bonded to two equivalent Li(1), two equivalent Li(3), and two equivalent Li(4) atoms to form corner-sharing OLi6 octahedra. The corner-sharing octahedra are not tilted.
Li7B18O crystallizes in the monoclinic P2/m space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded in a single-bond geometry to two equivalent B(4), two equivalent B(6), two equivalent B(9), and one O(1) atom. Both Li(1)-B(4) bond lengths are 2.69 Å. Both Li(1)-B(6) bond lengths are 2.48 Å. Both Li(1)-B(9) bond lengths are 2.49 Å. The Li(1)-O(1) bond length is 1.95 Å. In the second Li site, Li(2) is bonded in a 18-coordinate geometry to two equivalent B(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), two equivalent B(5), two equivalent B(6), two equivalent B(7), two equivalent B(8), and two equivalent B(9) atoms. Both Li(2)-B(1) bond lengths are 2.55 Å. Both Li(2)-B(2) bond lengths are 2.73 Å. Both Li(2)-B(3) bond lengths are 2.68 Å. Both Li(2)-B(4) bond lengths are 2.74 Å. Both Li(2)-B(5) bond lengths are 2.47 Å. Both Li(2)-B(6) bond lengths are 2.70 Å. Both Li(2)-B(7) bond lengths are 2.67 Å. Both Li(2)-B(8) bond lengths are 2.68 Å. Both Li(2)-B(9) bond lengths are 2.49 Å. In the third Li site, Li(3) is bonded in a linear geometry to two equivalent O(1) atoms. Both Li(3)-O(1) bond lengths are 2.06 Å. In the fourth Li site, Li(4) is bonded in a single-bond geometry to two equivalent B(3), two equivalent B(5), two equivalent B(7), and one O(1) atom. Both Li(4)-B(3) bond lengths are 2.49 Å. Both Li(4)-B(5) bond lengths are 2.40 Å. Both Li(4)-B(7) bond lengths are 2.74 Å. The Li(4)-O(1) bond length is 1.92 Å. There are nine inequivalent B sites. In the first B site, B(1) is bonded in a 7-coordinate geometry to two equivalent Li(2), one B(1), two equivalent B(2), and two equivalent B(4) atoms. The B(1)-B(1) bond length is 1.64 Å. Both B(1)-B(2) bond lengths are 1.76 Å. Both B(1)-B(4) bond lengths are 1.76 Å. In the second B site, B(2) is bonded in a 5-coordinate geometry to two equivalent Li(2), one B(3), two equivalent B(1), and two equivalent B(4) atoms. The B(2)-B(3) bond length is 1.68 Å. There is one shorter (1.73 Å) and one longer (1.82 Å) B(2)-B(4) bond length. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Li(2), two equivalent Li(4), one B(2), two equivalent B(5), and two equivalent B(7) atoms. Both B(3)-B(5) bond lengths are 1.75 Å. There is one shorter (1.75 Å) and one longer (1.82 Å) B(3)-B(7) bond length. In the fourth B site, B(4) is bonded in a 9-coordinate geometry to two equivalent Li(1), two equivalent Li(2), one B(6), two equivalent B(1), and two equivalent B(2) atoms. The B(4)-B(6) bond length is 1.68 Å. In the fifth B site, B(5) is bonded in a 9-coordinate geometry to two equivalent Li(2), two equivalent Li(4), one B(5), two equivalent B(3), and two equivalent B(7) atoms. The B(5)-B(5) bond length is 1.66 Å. Both B(5)-B(7) bond lengths are 1.76 Å. In the sixth B site, B(6) is bonded in a 9-coordinate geometry to two equivalent Li(1), two equivalent Li(2), one B(4), two equivalent B(8), and two equivalent B(9) atoms. There is one shorter (1.73 Å) and one longer (1.82 Å) B(6)-B(8) bond length. Both B(6)-B(9) bond lengths are 1.75 Å. In the seventh B site, B(7) is bonded in a 9-coordinate geometry to two equivalent Li(2), two equivalent Li(4), one B(8), two equivalent B(3), and two equivalent B(5) atoms. The B(7)-B(8) bond length is 1.67 Å. In the eighth B site, B(8) is bonded in a 7-coordinate geometry to two equivalent Li(2), one B(7), two equivalent B(6), and two equivalent B(9) atoms. Both B(8)-B(9) bond lengths are 1.76 Å. In the ninth B site, B(9) is bonded in a 9-coordinate geometry to two equivalent Li(1), two equivalent Li(2), one B(9), two equivalent B(6), and two equivalent B(8) atoms. The B(9)-B(9) bond length is 1.66 Å. O(1) is bonded to two equivalent Li(1), two equivalent Li(3), and two equivalent Li(4) atoms to form corner-sharing OLi6 octahedra. The corner-sharing octahedra are not tilted.