Li4CO4 is Matlockite-like structured and crystallizes in the monoclinic Cm space group. There are three 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(3) atoms. In the second Li site, Li(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(2)O4 tetrahedra and corners with four equivalent C(1)O4 tetrahedra. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. C(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form CO4 tetrahedra that share corners with eight equivalent Li(2)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Li(1), one Li(3), two equivalent Li(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Li(1), one Li(3), two equivalent Li(2), and one C(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Li(1), one Li(3), two equivalent Li(2), and one C(1) atom.
Li4CO4 is Matlockite-like structured and crystallizes in the monoclinic Cm space group. There are three 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(3) atoms. The Li(1)-O(1) bond length is 1.91 Å. The Li(1)-O(2) bond length is 2.06 Å. Both Li(1)-O(3) bond lengths are 2.19 Å. In the second Li site, Li(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(2)O4 tetrahedra and corners with four equivalent C(1)O4 tetrahedra. The Li(2)-O(1) bond length is 2.00 Å. The Li(2)-O(2) bond length is 1.91 Å. There is one shorter (1.93 Å) and one longer (1.97 Å) Li(2)-O(3) bond length. In the third Li site, Li(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. The Li(3)-O(1) bond length is 1.93 Å. The Li(3)-O(2) bond length is 2.18 Å. Both Li(3)-O(3) bond lengths are 1.93 Å. C(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form CO4 tetrahedra that share corners with eight equivalent Li(2)O4 tetrahedra. The C(1)-O(1) bond length is 1.41 Å. The C(1)-O(2) bond length is 1.44 Å. Both C(1)-O(3) bond lengths are 1.43 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Li(1), one Li(3), two equivalent Li(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Li(1), one Li(3), two equivalent Li(2), and one C(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Li(1), one Li(3), two equivalent Li(2), and one C(1) atom.