LiAlMnO4 crystallizes in the orthorhombic Pnma space group. Li(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(4), and three equivalent O(2) atoms. Mn(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with three equivalent Al(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-51°. Al(1) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form AlO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-51°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mn(1) and three equivalent Al(1) atoms to form OMnAl3 trigonal pyramids that share  a cornercorner with one O(4)Li2Mn2Al square pyramid, corners with two equivalent O(1)MnAl3 trigonal pyramids, corners with five equivalent O(3)LiMnAl2 trigonal pyramids, edges with two equivalent O(4)Li2Mn2Al square pyramids,  an edgeedge with one O(3)LiMnAl2 trigonal pyramid, and edges with two equivalent O(1)MnAl3 trigonal pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Li(1) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded to one Li(1), one Mn(1), and two equivalent Al(1) atoms to form OLiMnAl2 trigonal pyramids that share corners with two equivalent O(4)Li2Mn2Al square pyramids, corners with two equivalent O(3)LiMnAl2 trigonal pyramids, corners with five equivalent O(1)MnAl3 trigonal pyramids, edges with two equivalent O(4)Li2Mn2Al square pyramids, and  an edgeedge with one O(1)MnAl3 trigonal pyramid. In the fourth O site, O(4) is bonded to two equivalent Li(1), two equivalent Mn(1), and one Al(1) atom to form OLi2Mn2Al square pyramids that share  a cornercorner with one O(1)MnAl3 trigonal pyramid, corners with two equivalent O(3)LiMnAl2 trigonal pyramids, edges with two equivalent O(4)Li2Mn2Al square pyramids, edges with two equivalent O(3)LiMnAl2 trigonal pyramids, and edges with two equivalent O(1)MnAl3 trigonal pyramids.
LiAlMnO4 crystallizes in the orthorhombic Pnma space group. Li(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(4), and three equivalent O(2) atoms. The Li(1)-O(3) bond length is 2.22 Å. Both Li(1)-O(4) bond lengths are 2.15 Å. There is one shorter (1.96 Å) and two longer (2.47 Å) Li(1)-O(2) bond lengths. Mn(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with three equivalent Al(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-51°. The Mn(1)-O(1) bond length is 1.96 Å. The Mn(1)-O(3) bond length is 1.89 Å. Both Mn(1)-O(2) bond lengths are 1.91 Å. Both Mn(1)-O(4) bond lengths are 1.98 Å. Al(1) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form AlO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-51°. The Al(1)-O(4) bond length is 1.95 Å. Both Al(1)-O(3) bond lengths are 1.85 Å. There is one shorter (1.90 Å) and two longer (1.97 Å) Al(1)-O(1) bond lengths. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mn(1) and three equivalent Al(1) atoms to form OMnAl3 trigonal pyramids that share  a cornercorner with one O(4)Li2Mn2Al square pyramid, corners with two equivalent O(1)MnAl3 trigonal pyramids, corners with five equivalent O(3)LiMnAl2 trigonal pyramids, edges with two equivalent O(4)Li2Mn2Al square pyramids,  an edgeedge with one O(3)LiMnAl2 trigonal pyramid, and edges with two equivalent O(1)MnAl3 trigonal pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Li(1) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded to one Li(1), one Mn(1), and two equivalent Al(1) atoms to form OLiMnAl2 trigonal pyramids that share corners with two equivalent O(4)Li2Mn2Al square pyramids, corners with two equivalent O(3)LiMnAl2 trigonal pyramids, corners with five equivalent O(1)MnAl3 trigonal pyramids, edges with two equivalent O(4)Li2Mn2Al square pyramids, and  an edgeedge with one O(1)MnAl3 trigonal pyramid. In the fourth O site, O(4) is bonded to two equivalent Li(1), two equivalent Mn(1), and one Al(1) atom to form OLi2Mn2Al square pyramids that share  a cornercorner with one O(1)MnAl3 trigonal pyramid, corners with two equivalent O(3)LiMnAl2 trigonal pyramids, edges with two equivalent O(4)Li2Mn2Al square pyramids, edges with two equivalent O(3)LiMnAl2 trigonal pyramids, and edges with two equivalent O(1)MnAl3 trigonal pyramids.