Li4CO4 crystallizes in the orthorhombic Cmc2_1 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), and three equivalent O(1) atoms. In the second Li site, Li(2) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(1) atoms. In the third Li site, Li(3) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. C(1) is bonded in a tetrahedral geometry to one O(2), one O(3), and two equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to one Li(3), two equivalent Li(2), three equivalent Li(1), and one C(1) atom. In the second O site, O(2) is bonded to one Li(2), two equivalent Li(1), two equivalent Li(3), and one C(1) atom to form OLi5C octahedra that share corners with two equivalent O(2)Li5C octahedra, corners with three equivalent O(3)Li4C trigonal bipyramids, and edges with two equivalent O(3)Li4C trigonal bipyramids. The corner-sharing octahedral tilt angles are 26°. In the third O site, O(3) is bonded to two equivalent Li(1), two equivalent Li(3), and one C(1) atom to form distorted OLi4C trigonal bipyramids that share corners with three equivalent O(2)Li5C octahedra, corners with two equivalent O(3)Li4C trigonal bipyramids, and edges with two equivalent O(2)Li5C octahedra. The corner-sharing octahedral tilt angles range from 35-63°.
Li4CO4 crystallizes in the orthorhombic Cmc2_1 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), and three equivalent O(1) atoms. The Li(1)-O(2) bond length is 2.00 Å. The Li(1)-O(3) bond length is 1.99 Å. There are a spread of Li(1)-O(1) bond distances ranging from 2.05-2.29 Å. In the second Li site, Li(2) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(1) atoms. The Li(2)-O(2) bond length is 1.94 Å. There are two shorter (1.97 Å) and two longer (2.20 Å) Li(2)-O(1) bond lengths. In the third Li site, Li(3) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Both Li(3)-O(1) bond lengths are 2.52 Å. There is one shorter (1.99 Å) and one longer (2.04 Å) Li(3)-O(2) bond length. There is one shorter (2.13 Å) and one longer (2.19 Å) Li(3)-O(3) bond length. C(1) is bonded in a tetrahedral geometry to one O(2), one O(3), and two equivalent O(1) atoms. The C(1)-O(2) bond length is 1.44 Å. The C(1)-O(3) bond length is 1.38 Å. Both C(1)-O(1) bond lengths are 1.43 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to one Li(3), two equivalent Li(2), three equivalent Li(1), and one C(1) atom. In the second O site, O(2) is bonded to one Li(2), two equivalent Li(1), two equivalent Li(3), and one C(1) atom to form OLi5C octahedra that share corners with two equivalent O(2)Li5C octahedra, corners with three equivalent O(3)Li4C trigonal bipyramids, and edges with two equivalent O(3)Li4C trigonal bipyramids. The corner-sharing octahedral tilt angles are 26°. In the third O site, O(3) is bonded to two equivalent Li(1), two equivalent Li(3), and one C(1) atom to form distorted OLi4C trigonal bipyramids that share corners with three equivalent O(2)Li5C octahedra, corners with two equivalent O(3)Li4C trigonal bipyramids, and edges with two equivalent O(2)Li5C octahedra. The corner-sharing octahedral tilt angles range from 35-63°.