Li2CoAlO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form LiO5 trigonal bipyramids that share corners with two equivalent Li(1)O5 trigonal bipyramids, corners with two equivalent Li(2)O5 trigonal bipyramids, corners with four equivalent Al(1)O5 trigonal bipyramids,  an edgeedge with one Al(1)O5 trigonal bipyramid, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with three equivalent Co(1)O5 trigonal bipyramids. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(4), and two equivalent O(3) atoms to form LiO5 trigonal bipyramids that share corners with two equivalent Li(1)O5 trigonal bipyramids, corners with two equivalent Al(1)O5 trigonal bipyramids, corners with four equivalent Co(1)O5 trigonal bipyramids,  an edgeedge with one Li(2)O5 trigonal bipyramid,  an edgeedge with one Co(1)O5 trigonal bipyramid, edges with two equivalent Li(1)O5 trigonal bipyramids, and edges with two equivalent Al(1)O5 trigonal bipyramids. Co(1) is bonded to one O(1), one O(2), one O(3), and two equivalent O(4) atoms to form CoO5 trigonal bipyramids that share corners with two equivalent Co(1)O5 trigonal bipyramids, corners with two equivalent Al(1)O5 trigonal bipyramids, corners with four equivalent Li(2)O5 trigonal bipyramids,  an edgeedge with one Li(2)O5 trigonal bipyramid, edges with two equivalent Al(1)O5 trigonal bipyramids, and edges with three equivalent Li(1)O5 trigonal bipyramids. Al(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form AlO5 trigonal bipyramids that share corners with two equivalent Li(2)O5 trigonal bipyramids, corners with two equivalent Co(1)O5 trigonal bipyramids, corners with four equivalent Li(1)O5 trigonal bipyramids,  an edgeedge with one Li(1)O5 trigonal bipyramid,  an edgeedge with one Al(1)O5 trigonal bipyramid, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with two equivalent Co(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), one Co(1), and one Al(1) atom to form OLi3AlCo trigonal bipyramids that share corners with two equivalent O(1)Li3AlCo trigonal bipyramids, corners with two equivalent O(3)Li3AlCo trigonal bipyramids, corners with four equivalent O(2)Li2Al2Co trigonal bipyramids,  an edgeedge with one O(2)Li2Al2Co trigonal bipyramid, edges with two equivalent O(3)Li3AlCo trigonal bipyramids, and edges with three equivalent O(4)Li2AlCo2 trigonal bipyramids. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Co(1), and two equivalent Al(1) atoms to form OLi2Al2Co trigonal bipyramids that share corners with two equivalent O(4)Li2AlCo2 trigonal bipyramids, corners with two equivalent O(3)Li3AlCo trigonal bipyramids, corners with four equivalent O(1)Li3AlCo trigonal bipyramids,  an edgeedge with one O(2)Li2Al2Co trigonal bipyramid,  an edgeedge with one O(1)Li3AlCo trigonal bipyramid, edges with two equivalent O(4)Li2AlCo2 trigonal bipyramids, and edges with two equivalent O(3)Li3AlCo trigonal bipyramids. In the third O site, O(3) is bonded to one Li(1), two equivalent Li(2), one Co(1), and one Al(1) atom to form OLi3AlCo trigonal bipyramids that share corners with two equivalent O(2)Li2Al2Co trigonal bipyramids, corners with two equivalent O(1)Li3AlCo trigonal bipyramids, corners with four equivalent O(4)Li2AlCo2 trigonal bipyramids,  an edgeedge with one O(4)Li2AlCo2 trigonal bipyramid,  an edgeedge with one O(3)Li3AlCo trigonal bipyramid, edges with two equivalent O(2)Li2Al2Co trigonal bipyramids, and edges with two equivalent O(1)Li3AlCo trigonal bipyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), two equivalent Co(1), and one Al(1) atom to form OLi2AlCo2 trigonal bipyramids that share corners with two equivalent O(2)Li2Al2Co trigonal bipyramids, corners with two equivalent O(4)Li2AlCo2 trigonal bipyramids, corners with four equivalent O(3)Li3AlCo trigonal bipyramids,  an edgeedge with one O(3)Li3AlCo trigonal bipyramid, edges with two equivalent O(2)Li2Al2Co trigonal bipyramids, and edges with three equivalent O(1)Li3AlCo trigonal bipyramids.
Li2CoAlO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form LiO5 trigonal bipyramids that share corners with two equivalent Li(1)O5 trigonal bipyramids, corners with two equivalent Li(2)O5 trigonal bipyramids, corners with four equivalent Al(1)O5 trigonal bipyramids,  an edgeedge with one Al(1)O5 trigonal bipyramid, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with three equivalent Co(1)O5 trigonal bipyramids. The Li(1)-O(2) bond length is 2.03 Å. The Li(1)-O(3) bond length is 2.14 Å. The Li(1)-O(4) bond length is 2.12 Å. There is one shorter (1.98 Å) and one longer (2.03 Å) Li(1)-O(1) bond length. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(4), and two equivalent O(3) atoms to form LiO5 trigonal bipyramids that share corners with two equivalent Li(1)O5 trigonal bipyramids, corners with two equivalent Al(1)O5 trigonal bipyramids, corners with four equivalent Co(1)O5 trigonal bipyramids,  an edgeedge with one Li(2)O5 trigonal bipyramid,  an edgeedge with one Co(1)O5 trigonal bipyramid, edges with two equivalent Li(1)O5 trigonal bipyramids, and edges with two equivalent Al(1)O5 trigonal bipyramids. The Li(2)-O(1) bond length is 2.02 Å. The Li(2)-O(2) bond length is 2.05 Å. The Li(2)-O(4) bond length is 2.06 Å. There is one shorter (2.04 Å) and one longer (2.13 Å) Li(2)-O(3) bond length. Co(1) is bonded to one O(1), one O(2), one O(3), and two equivalent O(4) atoms to form CoO5 trigonal bipyramids that share corners with two equivalent Co(1)O5 trigonal bipyramids, corners with two equivalent Al(1)O5 trigonal bipyramids, corners with four equivalent Li(2)O5 trigonal bipyramids,  an edgeedge with one Li(2)O5 trigonal bipyramid, edges with two equivalent Al(1)O5 trigonal bipyramids, and edges with three equivalent Li(1)O5 trigonal bipyramids. The Co(1)-O(1) bond length is 2.00 Å. The Co(1)-O(2) bond length is 2.16 Å. The Co(1)-O(3) bond length is 1.82 Å. There is one shorter (1.96 Å) and one longer (1.97 Å) Co(1)-O(4) bond length. Al(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form AlO5 trigonal bipyramids that share corners with two equivalent Li(2)O5 trigonal bipyramids, corners with two equivalent Co(1)O5 trigonal bipyramids, corners with four equivalent Li(1)O5 trigonal bipyramids,  an edgeedge with one Li(1)O5 trigonal bipyramid,  an edgeedge with one Al(1)O5 trigonal bipyramid, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with two equivalent Co(1)O5 trigonal bipyramids. The Al(1)-O(1) bond length is 1.80 Å. The Al(1)-O(3) bond length is 1.84 Å. The Al(1)-O(4) bond length is 1.95 Å. There is one shorter (1.83 Å) and one longer (1.95 Å) Al(1)-O(2) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), one Co(1), and one Al(1) atom to form OLi3AlCo trigonal bipyramids that share corners with two equivalent O(1)Li3AlCo trigonal bipyramids, corners with two equivalent O(3)Li3AlCo trigonal bipyramids, corners with four equivalent O(2)Li2Al2Co trigonal bipyramids,  an edgeedge with one O(2)Li2Al2Co trigonal bipyramid, edges with two equivalent O(3)Li3AlCo trigonal bipyramids, and edges with three equivalent O(4)Li2AlCo2 trigonal bipyramids. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Co(1), and two equivalent Al(1) atoms to form OLi2Al2Co trigonal bipyramids that share corners with two equivalent O(4)Li2AlCo2 trigonal bipyramids, corners with two equivalent O(3)Li3AlCo trigonal bipyramids, corners with four equivalent O(1)Li3AlCo trigonal bipyramids,  an edgeedge with one O(2)Li2Al2Co trigonal bipyramid,  an edgeedge with one O(1)Li3AlCo trigonal bipyramid, edges with two equivalent O(4)Li2AlCo2 trigonal bipyramids, and edges with two equivalent O(3)Li3AlCo trigonal bipyramids. In the third O site, O(3) is bonded to one Li(1), two equivalent Li(2), one Co(1), and one Al(1) atom to form OLi3AlCo trigonal bipyramids that share corners with two equivalent O(2)Li2Al2Co trigonal bipyramids, corners with two equivalent O(1)Li3AlCo trigonal bipyramids, corners with four equivalent O(4)Li2AlCo2 trigonal bipyramids,  an edgeedge with one O(4)Li2AlCo2 trigonal bipyramid,  an edgeedge with one O(3)Li3AlCo trigonal bipyramid, edges with two equivalent O(2)Li2Al2Co trigonal bipyramids, and edges with two equivalent O(1)Li3AlCo trigonal bipyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), two equivalent Co(1), and one Al(1) atom to form OLi2AlCo2 trigonal bipyramids that share corners with two equivalent O(2)Li2Al2Co trigonal bipyramids, corners with two equivalent O(4)Li2AlCo2 trigonal bipyramids, corners with four equivalent O(3)Li3AlCo trigonal bipyramids,  an edgeedge with one O(3)Li3AlCo trigonal bipyramid, edges with two equivalent O(2)Li2Al2Co trigonal bipyramids, and edges with three equivalent O(1)Li3AlCo trigonal bipyramids.