P3N5 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent P sites. In the first P site, P(1) is bonded to two equivalent N(2) and three equivalent N(1) atoms to form PN5 square pyramids that share corners with four equivalent P(1)N5 square pyramids, corners with two equivalent P(2)N4 tetrahedra, and edges with two equivalent P(1)N5 square pyramids. In the second P site, P(2) is bonded to two equivalent N(2) and two equivalent N(3) atoms to form PN4 tetrahedra that share corners with four equivalent P(1)N5 square pyramids and corners with two equivalent P(2)N4 tetrahedra. There are three inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to three equivalent P(1) atoms. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one P(2) and two equivalent P(1) atoms. In the third N site, N(3) is bonded in a bent 120 degrees geometry to two equivalent P(2) atoms.
P3N5 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent P sites. In the first P site, P(1) is bonded to two equivalent N(2) and three equivalent N(1) atoms to form PN5 square pyramids that share corners with four equivalent P(1)N5 square pyramids, corners with two equivalent P(2)N4 tetrahedra, and edges with two equivalent P(1)N5 square pyramids. Both P(1)-N(2) bond lengths are 1.75 Å. There is one shorter (1.72 Å) and two longer (1.75 Å) P(1)-N(1) bond lengths. In the second P site, P(2) is bonded to two equivalent N(2) and two equivalent N(3) atoms to form PN4 tetrahedra that share corners with four equivalent P(1)N5 square pyramids and corners with two equivalent P(2)N4 tetrahedra. Both P(2)-N(2) bond lengths are 1.68 Å. Both P(2)-N(3) bond lengths are 1.58 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to three equivalent P(1) atoms. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one P(2) and two equivalent P(1) atoms. In the third N site, N(3) is bonded in a bent 120 degrees geometry to two equivalent P(2) atoms.