LiAl(PO4)(OH) crystallizes in the triclinic P-1 space group. Li(1) is bonded to one O(1), one O(2), one O(5), and two equivalent O(3) atoms to form distorted LiO5 square pyramids that share corners with two equivalent Al(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, edges with two equivalent Al(2)O6 octahedra,  an edgeedge with one Li(1)O5 square pyramid, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-66°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with two equivalent Al(2)O6 octahedra, corners with four equivalent Li(1)O5 square pyramids, and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. In the second Al site, Al(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with two equivalent Al(1)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and edges with four equivalent Li(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 45°. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra, corners with two equivalent Al(2)O6 octahedra, corners with two equivalent Li(1)O5 square pyramids, and  an edgeedge with one Li(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 33-52°. H(1) is bonded in a single-bond geometry to one O(5) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(1), one Al(1), and one P(1) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Li(1), one Al(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li(1), one Al(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Al(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Li(1), one Al(1), one Al(2), and one H(1) atom.
LiAl(PO4)(OH) crystallizes in the triclinic P-1 space group. Li(1) is bonded to one O(1), one O(2), one O(5), and two equivalent O(3) atoms to form distorted LiO5 square pyramids that share corners with two equivalent Al(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, edges with two equivalent Al(2)O6 octahedra,  an edgeedge with one Li(1)O5 square pyramid, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-66°. The Li(1)-O(1) bond length is 2.11 Å. The Li(1)-O(2) bond length is 2.07 Å. The Li(1)-O(5) bond length is 2.00 Å. There is one shorter (2.06 Å) and one longer (2.15 Å) Li(1)-O(3) bond length. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with two equivalent Al(2)O6 octahedra, corners with four equivalent Li(1)O5 square pyramids, and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. Both Al(1)-O(1) bond lengths are 1.93 Å. Both Al(1)-O(4) bond lengths are 1.94 Å. Both Al(1)-O(5) bond lengths are 1.92 Å. In the second Al site, Al(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with two equivalent Al(1)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and edges with four equivalent Li(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 45°. Both Al(2)-O(2) bond lengths are 1.87 Å. Both Al(2)-O(3) bond lengths are 1.94 Å. Both Al(2)-O(5) bond lengths are 1.93 Å. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra, corners with two equivalent Al(2)O6 octahedra, corners with two equivalent Li(1)O5 square pyramids, and  an edgeedge with one Li(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 33-52°. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(2) bond length is 1.54 Å. The P(1)-O(3) bond length is 1.56 Å. The P(1)-O(4) bond length is 1.55 Å. H(1) is bonded in a single-bond geometry to one O(5) atom. The H(1)-O(5) bond length is 0.99 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(1), one Al(1), and one P(1) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Li(1), one Al(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li(1), one Al(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Al(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Li(1), one Al(1), one Al(2), and one H(1) atom.