LiNiPO4 crystallizes in the orthorhombic Pna2_1 space group. Li(1) is bonded in a trigonal non-coplanar geometry to one O(4) and two equivalent O(2) atoms. Ni(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted NiO5 trigonal bipyramids that share corners with three equivalent P(1)O4 tetrahedra, corners with two equivalent Ni(1)O5 trigonal bipyramids, and  an edgeedge with one P(1)O4 tetrahedra. 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 Ni(1)O5 trigonal bipyramids and  an edgeedge with one Ni(1)O5 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Ni(1) and one P(1) atom. In the second O site, O(2) is bonded to two equivalent Li(1), one Ni(1), and one P(1) atom to form distorted corner-sharing OLi2NiP tetrahedra. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Ni(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 Ni(1), and one P(1) atom.
LiNiPO4 crystallizes in the orthorhombic Pna2_1 space group. Li(1) is bonded in a trigonal non-coplanar geometry to one O(4) and two equivalent O(2) atoms. The Li(1)-O(4) bond length is 1.99 Å. There is one shorter (1.99 Å) and one longer (2.06 Å) Li(1)-O(2) bond length. Ni(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted NiO5 trigonal bipyramids that share corners with three equivalent P(1)O4 tetrahedra, corners with two equivalent Ni(1)O5 trigonal bipyramids, and  an edgeedge with one P(1)O4 tetrahedra. The Ni(1)-O(2) bond length is 2.20 Å. The Ni(1)-O(3) bond length is 2.02 Å. The Ni(1)-O(4) bond length is 1.96 Å. There is one shorter (2.00 Å) and one longer (2.02 Å) Ni(1)-O(1) bond length. 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 Ni(1)O5 trigonal bipyramids and  an edgeedge with one Ni(1)O5 trigonal bipyramid. The P(1)-O(1) bond length is 1.57 Å. The P(1)-O(2) bond length is 1.57 Å. The P(1)-O(3) bond length is 1.53 Å. The P(1)-O(4) bond length is 1.55 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Ni(1) and one P(1) atom. In the second O site, O(2) is bonded to two equivalent Li(1), one Ni(1), and one P(1) atom to form distorted corner-sharing OLi2NiP tetrahedra. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Ni(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 Ni(1), and one P(1) atom.