LiCuPO4 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to one O(4), one O(7), and two equivalent O(1) atoms. In the second Li site, Li(2) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(6), and one O(8) atom. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1), one O(2), one O(3), one O(6), and one O(8) atom to form distorted CuO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra and corners with three equivalent P(1)O4 tetrahedra. In the second Cu site, Cu(2) is bonded in a 6-coordinate geometry to one O(4), one O(6), one O(7), one O(8), and two equivalent O(5) atoms. There are two inequivalent P sites. In the first P site, 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 three equivalent Cu(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Li(1), one Cu(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Li(2), one Cu(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(2), one Cu(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(1), one Cu(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Cu(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Li(2), one Cu(1), one Cu(2), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Li(1), one Cu(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Li(2), one Cu(1), one Cu(2), and one P(2) atom.
LiCuPO4 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to one O(4), one O(7), and two equivalent O(1) atoms. The Li(1)-O(4) bond length is 1.97 Å. The Li(1)-O(7) bond length is 2.50 Å. There is one shorter (1.97 Å) and one longer (2.40 Å) Li(1)-O(1) bond length. In the second Li site, Li(2) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(6), and one O(8) atom. The Li(2)-O(2) bond length is 1.96 Å. The Li(2)-O(3) bond length is 2.17 Å. The Li(2)-O(6) bond length is 2.49 Å. The Li(2)-O(8) bond length is 1.93 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1), one O(2), one O(3), one O(6), and one O(8) atom to form distorted CuO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra and corners with three equivalent P(1)O4 tetrahedra. The Cu(1)-O(1) bond length is 2.42 Å. The Cu(1)-O(2) bond length is 2.05 Å. The Cu(1)-O(3) bond length is 1.95 Å. The Cu(1)-O(6) bond length is 1.99 Å. The Cu(1)-O(8) bond length is 2.09 Å. In the second Cu site, Cu(2) is bonded in a 6-coordinate geometry to one O(4), one O(6), one O(7), one O(8), and two equivalent O(5) atoms. The Cu(2)-O(4) bond length is 2.03 Å. The Cu(2)-O(6) bond length is 2.22 Å. The Cu(2)-O(7) bond length is 1.90 Å. The Cu(2)-O(8) bond length is 2.52 Å. There is one shorter (1.89 Å) and one longer (2.37 Å) Cu(2)-O(5) bond length. There are two inequivalent P sites. In the first P site, 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 three equivalent Cu(1)O5 trigonal bipyramids. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(2) bond length is 1.57 Å. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.56 Å. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 trigonal bipyramids. The P(2)-O(5) bond length is 1.55 Å. The P(2)-O(6) bond length is 1.58 Å. The P(2)-O(7) bond length is 1.54 Å. The P(2)-O(8) bond length is 1.55 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Li(1), one Cu(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Li(2), one Cu(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(2), one Cu(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(1), one Cu(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Cu(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Li(2), one Cu(1), one Cu(2), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Li(1), one Cu(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Li(2), one Cu(1), one Cu(2), and one P(2) atom.