Li2MnAlO4 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 Mn(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 Mn(1)O5 trigonal bipyramids,  an edgeedge with one Li(2)O5 trigonal bipyramid,  an edgeedge with one Mn(1)O5 trigonal bipyramid, edges with two equivalent Li(1)O5 trigonal bipyramids, and edges with two equivalent Al(1)O5 trigonal bipyramids. Mn(1) is bonded to one O(1), one O(2), one O(3), and two equivalent O(4) atoms to form MnO5 trigonal bipyramids that share corners with two equivalent Mn(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 Mn(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 Mn(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 Mn(1), and one Al(1) atom to form OLi3MnAl trigonal bipyramids that share corners with two equivalent O(1)Li3MnAl trigonal bipyramids, corners with two equivalent O(3)Li3MnAl trigonal bipyramids, corners with four equivalent O(2)Li2MnAl2 trigonal bipyramids,  an edgeedge with one O(2)Li2MnAl2 trigonal bipyramid, edges with two equivalent O(3)Li3MnAl trigonal bipyramids, and edges with three equivalent O(4)Li2Mn2Al trigonal bipyramids. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Mn(1), and two equivalent Al(1) atoms to form OLi2MnAl2 trigonal bipyramids that share corners with two equivalent O(4)Li2Mn2Al trigonal bipyramids, corners with two equivalent O(3)Li3MnAl trigonal bipyramids, corners with four equivalent O(1)Li3MnAl trigonal bipyramids,  an edgeedge with one O(2)Li2MnAl2 trigonal bipyramid,  an edgeedge with one O(1)Li3MnAl trigonal bipyramid, edges with two equivalent O(4)Li2Mn2Al trigonal bipyramids, and edges with two equivalent O(3)Li3MnAl trigonal bipyramids. In the third O site, O(3) is bonded to one Li(1), two equivalent Li(2), one Mn(1), and one Al(1) atom to form OLi3MnAl trigonal bipyramids that share corners with two equivalent O(2)Li2MnAl2 trigonal bipyramids, corners with two equivalent O(1)Li3MnAl trigonal bipyramids, corners with four equivalent O(4)Li2Mn2Al trigonal bipyramids,  an edgeedge with one O(4)Li2Mn2Al trigonal bipyramid,  an edgeedge with one O(3)Li3MnAl trigonal bipyramid, edges with two equivalent O(2)Li2MnAl2 trigonal bipyramids, and edges with two equivalent O(1)Li3MnAl trigonal bipyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), two equivalent Mn(1), and one Al(1) atom to form OLi2Mn2Al trigonal bipyramids that share corners with two equivalent O(4)Li2Mn2Al trigonal bipyramids, corners with two equivalent O(2)Li2MnAl2 trigonal bipyramids, corners with four equivalent O(3)Li3MnAl trigonal bipyramids,  an edgeedge with one O(3)Li3MnAl trigonal bipyramid, edges with two equivalent O(2)Li2MnAl2 trigonal bipyramids, and edges with three equivalent O(1)Li3MnAl trigonal bipyramids.
Li2MnAlO4 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 Mn(1)O5 trigonal bipyramids. The Li(1)-O(2) bond length is 2.20 Å. The Li(1)-O(3) bond length is 2.00 Å. The Li(1)-O(4) bond length is 2.00 Å. There is one shorter (2.06 Å) and one longer (2.08 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 Mn(1)O5 trigonal bipyramids,  an edgeedge with one Li(2)O5 trigonal bipyramid,  an edgeedge with one Mn(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 2.05 Å. The Li(2)-O(2) bond length is 2.11 Å. The Li(2)-O(4) bond length is 2.01 Å. There is one shorter (2.02 Å) and one longer (2.11 Å) Li(2)-O(3) bond length. Mn(1) is bonded to one O(1), one O(2), one O(3), and two equivalent O(4) atoms to form MnO5 trigonal bipyramids that share corners with two equivalent Mn(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 Mn(1)-O(1) bond length is 1.91 Å. The Mn(1)-O(2) bond length is 2.00 Å. The Mn(1)-O(3) bond length is 1.96 Å. There is one shorter (1.97 Å) and one longer (2.10 Å) Mn(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 Mn(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 Mn(1)O5 trigonal bipyramids. The Al(1)-O(1) bond length is 1.82 Å. The Al(1)-O(3) bond length is 1.79 Å. The Al(1)-O(4) bond length is 1.93 Å. There is one shorter (1.85 Å) and one longer (1.98 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 Mn(1), and one Al(1) atom to form OLi3MnAl trigonal bipyramids that share corners with two equivalent O(1)Li3MnAl trigonal bipyramids, corners with two equivalent O(3)Li3MnAl trigonal bipyramids, corners with four equivalent O(2)Li2MnAl2 trigonal bipyramids,  an edgeedge with one O(2)Li2MnAl2 trigonal bipyramid, edges with two equivalent O(3)Li3MnAl trigonal bipyramids, and edges with three equivalent O(4)Li2Mn2Al trigonal bipyramids. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Mn(1), and two equivalent Al(1) atoms to form OLi2MnAl2 trigonal bipyramids that share corners with two equivalent O(4)Li2Mn2Al trigonal bipyramids, corners with two equivalent O(3)Li3MnAl trigonal bipyramids, corners with four equivalent O(1)Li3MnAl trigonal bipyramids,  an edgeedge with one O(2)Li2MnAl2 trigonal bipyramid,  an edgeedge with one O(1)Li3MnAl trigonal bipyramid, edges with two equivalent O(4)Li2Mn2Al trigonal bipyramids, and edges with two equivalent O(3)Li3MnAl trigonal bipyramids. In the third O site, O(3) is bonded to one Li(1), two equivalent Li(2), one Mn(1), and one Al(1) atom to form OLi3MnAl trigonal bipyramids that share corners with two equivalent O(2)Li2MnAl2 trigonal bipyramids, corners with two equivalent O(1)Li3MnAl trigonal bipyramids, corners with four equivalent O(4)Li2Mn2Al trigonal bipyramids,  an edgeedge with one O(4)Li2Mn2Al trigonal bipyramid,  an edgeedge with one O(3)Li3MnAl trigonal bipyramid, edges with two equivalent O(2)Li2MnAl2 trigonal bipyramids, and edges with two equivalent O(1)Li3MnAl trigonal bipyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), two equivalent Mn(1), and one Al(1) atom to form OLi2Mn2Al trigonal bipyramids that share corners with two equivalent O(4)Li2Mn2Al trigonal bipyramids, corners with two equivalent O(2)Li2MnAl2 trigonal bipyramids, corners with four equivalent O(3)Li3MnAl trigonal bipyramids,  an edgeedge with one O(3)Li3MnAl trigonal bipyramid, edges with two equivalent O(2)Li2MnAl2 trigonal bipyramids, and edges with three equivalent O(1)Li3MnAl trigonal bipyramids.