Li3CoBSiO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(4) atoms. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. Co(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with four equivalent Si(1)O4 tetrahedra. B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. Si(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-52°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), two equivalent Li(2), and one B(1) atom to form OLi3B tetrahedra that share corners with three equivalent O(3)Li2CoB tetrahedra and corners with four equivalent O(4)Li2CoSi trigonal pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Li(1), two equivalent Li(2), one Co(1), and one B(1) atom. In the third O site, O(3) is bonded to two equivalent Li(2), one Co(1), and one B(1) atom to form distorted OLi2CoB tetrahedra that share corners with three equivalent O(1)Li3B tetrahedra and corners with four equivalent O(4)Li2CoSi trigonal pyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Co(1), and one Si(1) atom to form distorted OLi2CoSi trigonal pyramids that share corners with two equivalent O(3)Li2CoB tetrahedra, corners with two equivalent O(1)Li3B tetrahedra,  a cornercorner with one O(4)Li2CoSi trigonal pyramid, and  an edgeedge with one O(4)Li2CoSi trigonal pyramid. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to two equivalent Li(2), one Co(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to two equivalent Li(2), one Co(1), and one Si(1) atom.
Li3CoBSiO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(4) atoms. The Li(1)-O(1) bond length is 2.00 Å. The Li(1)-O(2) bond length is 2.00 Å. Both Li(1)-O(4) bond lengths are 2.08 Å. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Li(2)-O(1) bond length is 1.97 Å. The Li(2)-O(2) bond length is 2.55 Å. The Li(2)-O(3) bond length is 2.10 Å. The Li(2)-O(4) bond length is 2.20 Å. The Li(2)-O(5) bond length is 2.59 Å. The Li(2)-O(6) bond length is 2.04 Å. Co(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with four equivalent Si(1)O4 tetrahedra. The Co(1)-O(2) bond length is 1.98 Å. The Co(1)-O(3) bond length is 1.87 Å. The Co(1)-O(5) bond length is 1.92 Å. The Co(1)-O(6) bond length is 1.89 Å. Both Co(1)-O(4) bond lengths are 1.86 Å. 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 1.34 Å. The B(1)-O(2) bond length is 1.39 Å. The B(1)-O(3) bond length is 1.40 Å. Si(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-52°. The Si(1)-O(5) bond length is 1.64 Å. The Si(1)-O(6) bond length is 1.62 Å. Both Si(1)-O(4) bond lengths are 1.66 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), two equivalent Li(2), and one B(1) atom to form OLi3B tetrahedra that share corners with three equivalent O(3)Li2CoB tetrahedra and corners with four equivalent O(4)Li2CoSi trigonal pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Li(1), two equivalent Li(2), one Co(1), and one B(1) atom. In the third O site, O(3) is bonded to two equivalent Li(2), one Co(1), and one B(1) atom to form distorted OLi2CoB tetrahedra that share corners with three equivalent O(1)Li3B tetrahedra and corners with four equivalent O(4)Li2CoSi trigonal pyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Co(1), and one Si(1) atom to form distorted OLi2CoSi trigonal pyramids that share corners with two equivalent O(3)Li2CoB tetrahedra, corners with two equivalent O(1)Li3B tetrahedra,  a cornercorner with one O(4)Li2CoSi trigonal pyramid, and  an edgeedge with one O(4)Li2CoSi trigonal pyramid. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to two equivalent Li(2), one Co(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to two equivalent Li(2), one Co(1), and one Si(1) atom.