LiCaPO4 crystallizes in the trigonal P31c space group. Li(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. Ca(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(6), two equivalent O(1), and two equivalent O(5) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(4) and three equivalent O(5) atoms to form PO4 tetrahedra that share corners with six equivalent Li(1)O4 tetrahedra. In the second P site, P(2) is bonded to one O(6) and three equivalent O(2) atoms to form PO4 tetrahedra that share corners with three equivalent Li(1)O4 tetrahedra. In the third P site, P(3) is bonded to one O(3) and three equivalent O(1) atoms to form PO4 tetrahedra that share corners with three equivalent Li(1)O4 tetrahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded in a 3-coordinate geometry to one Li(1), two equivalent Ca(1), and one P(1) atom. In the second O site, O(6) is bonded in a distorted tetrahedral geometry to three equivalent Ca(1) and one P(2) atom. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Li(1), two equivalent Ca(1), and one P(3) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Ca(1), and one P(2) atom. In the fifth O site, O(3) is bonded in a distorted single-bond geometry to three equivalent Ca(1) and one P(3) atom. In the sixth O site, O(4) is bonded in a distorted trigonal pyramidal geometry to three equivalent Li(1) and one P(1) atom.
LiCaPO4 crystallizes in the trigonal P31c space group. Li(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. The Li(1)-O(1) bond length is 1.98 Å. The Li(1)-O(2) bond length is 1.95 Å. The Li(1)-O(4) bond length is 1.97 Å. The Li(1)-O(5) bond length is 2.04 Å. Ca(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(6), two equivalent O(1), and two equivalent O(5) atoms. The Ca(1)-O(2) bond length is 2.30 Å. The Ca(1)-O(3) bond length is 2.56 Å. The Ca(1)-O(6) bond length is 2.40 Å. There is one shorter (2.44 Å) and one longer (2.58 Å) Ca(1)-O(1) bond length. There is one shorter (2.35 Å) and one longer (2.97 Å) Ca(1)-O(5) bond length. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(4) and three equivalent O(5) atoms to form PO4 tetrahedra that share corners with six equivalent Li(1)O4 tetrahedra. The P(1)-O(4) bond length is 1.56 Å. All P(1)-O(5) bond lengths are 1.57 Å. In the second P site, P(2) is bonded to one O(6) and three equivalent O(2) atoms to form PO4 tetrahedra that share corners with three equivalent Li(1)O4 tetrahedra. The P(2)-O(6) bond length is 1.57 Å. All P(2)-O(2) bond lengths are 1.54 Å. In the third P site, P(3) is bonded to one O(3) and three equivalent O(1) atoms to form PO4 tetrahedra that share corners with three equivalent Li(1)O4 tetrahedra. The P(3)-O(3) bond length is 1.55 Å. All P(3)-O(1) bond lengths are 1.56 Å. There are six inequivalent O sites. In the first O site, O(5) is bonded in a 3-coordinate geometry to one Li(1), two equivalent Ca(1), and one P(1) atom. In the second O site, O(6) is bonded in a distorted tetrahedral geometry to three equivalent Ca(1) and one P(2) atom. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Li(1), two equivalent Ca(1), and one P(3) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Ca(1), and one P(2) atom. In the fifth O site, O(3) is bonded in a distorted single-bond geometry to three equivalent Ca(1) and one P(3) atom. In the sixth O site, O(4) is bonded in a distorted trigonal pyramidal geometry to three equivalent Li(1) and one P(1) atom.