Na2LiAlP2 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to two equivalent P(1) and three equivalent P(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to two equivalent P(2) and three equivalent P(1) atoms. Li(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form distorted LiP4 tetrahedra that share corners with two equivalent Li(1)P4 tetrahedra, corners with two equivalent Al(1)P4 tetrahedra,  an edgeedge with one Li(1)P4 tetrahedra, and edges with three equivalent Al(1)P4 tetrahedra. Al(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form distorted AlP4 tetrahedra that share corners with two equivalent Li(1)P4 tetrahedra, corners with two equivalent Al(1)P4 tetrahedra,  an edgeedge with one Al(1)P4 tetrahedra, and edges with three equivalent Li(1)P4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to two equivalent Na(1), three equivalent Na(2), two equivalent Li(1), and two equivalent Al(1) atoms. In the second P site, P(2) is bonded in a 9-coordinate geometry to two equivalent Na(2), three equivalent Na(1), two equivalent Li(1), and two equivalent Al(1) atoms.
Na2LiAlP2 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to two equivalent P(1) and three equivalent P(2) atoms. Both Na(1)-P(1) bond lengths are 3.09 Å. There is one shorter (2.96 Å) and two longer (3.10 Å) Na(1)-P(2) bond lengths. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to two equivalent P(2) and three equivalent P(1) atoms. Both Na(2)-P(2) bond lengths are 3.09 Å. There is one shorter (2.97 Å) and two longer (3.07 Å) Na(2)-P(1) bond lengths. Li(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form distorted LiP4 tetrahedra that share corners with two equivalent Li(1)P4 tetrahedra, corners with two equivalent Al(1)P4 tetrahedra,  an edgeedge with one Li(1)P4 tetrahedra, and edges with three equivalent Al(1)P4 tetrahedra. Both Li(1)-P(1) bond lengths are 2.58 Å. Both Li(1)-P(2) bond lengths are 2.52 Å. Al(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form distorted AlP4 tetrahedra that share corners with two equivalent Li(1)P4 tetrahedra, corners with two equivalent Al(1)P4 tetrahedra,  an edgeedge with one Al(1)P4 tetrahedra, and edges with three equivalent Li(1)P4 tetrahedra. Both Al(1)-P(1) bond lengths are 2.41 Å. Both Al(1)-P(2) bond lengths are 2.44 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to two equivalent Na(1), three equivalent Na(2), two equivalent Li(1), and two equivalent Al(1) atoms. In the second P site, P(2) is bonded in a 9-coordinate geometry to two equivalent Na(2), three equivalent Na(1), two equivalent Li(1), and two equivalent Al(1) atoms.