NiP4 is Sylvanite-derived structured and crystallizes in the monoclinic C2/c space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent P(1), two equivalent P(3), and two equivalent P(4) atoms to form NiP6 octahedra that share corners with two equivalent P(1)Ni2P2 tetrahedra, corners with four equivalent P(4)Ni2P2 tetrahedra, corners with four equivalent P(2)NiP3 tetrahedra, corners with four equivalent P(3)NiP3 tetrahedra, and edges with two equivalent Ni(2)P6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent P(1), two equivalent P(2), and two equivalent P(4) atoms to form NiP6 octahedra that share corners with two equivalent P(4)Ni2P2 tetrahedra, corners with four equivalent P(1)Ni2P2 tetrahedra, corners with four equivalent P(2)NiP3 tetrahedra, corners with four equivalent P(3)NiP3 tetrahedra, and edges with two equivalent Ni(1)P6 octahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one Ni(1), one Ni(2), one P(1), and one P(2) atom to form distorted PNi2P2 tetrahedra that share  a cornercorner with one Ni(1)P6 octahedra, corners with two equivalent Ni(2)P6 octahedra, corners with two equivalent P(1)Ni2P2 tetrahedra, corners with two equivalent P(4)Ni2P2 tetrahedra, corners with three equivalent P(3)NiP3 tetrahedra, corners with four equivalent P(2)NiP3 tetrahedra, and  an edgeedge with one P(4)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 56-67°. In the second P site, P(2) is bonded to one Ni(2), one P(1), one P(2), and one P(3) atom to form distorted PNiP3 tetrahedra that share corners with two equivalent Ni(1)P6 octahedra, corners with two equivalent Ni(2)P6 octahedra,  a cornercorner with one P(2)NiP3 tetrahedra, corners with two equivalent P(3)NiP3 tetrahedra, corners with three equivalent P(4)Ni2P2 tetrahedra, and corners with four equivalent P(1)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 54-75°. In the third P site, P(3) is bonded to one Ni(1), one P(2), one P(3), and one P(4) atom to form distorted PNiP3 tetrahedra that share corners with two equivalent Ni(1)P6 octahedra, corners with two equivalent Ni(2)P6 octahedra,  a cornercorner with one P(3)NiP3 tetrahedra, corners with two equivalent P(2)NiP3 tetrahedra, corners with three equivalent P(1)Ni2P2 tetrahedra, and corners with four equivalent P(4)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 59-65°. In the fourth P site, P(4) is bonded to one Ni(1), one Ni(2), one P(3), and one P(4) atom to form distorted PNi2P2 tetrahedra that share  a cornercorner with one Ni(2)P6 octahedra, corners with two equivalent Ni(1)P6 octahedra, corners with two equivalent P(1)Ni2P2 tetrahedra, corners with two equivalent P(4)Ni2P2 tetrahedra, corners with three equivalent P(2)NiP3 tetrahedra, corners with four equivalent P(3)NiP3 tetrahedra, and  an edgeedge with one P(1)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 51-68°.
NiP4 is Sylvanite-derived structured and crystallizes in the monoclinic C2/c space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent P(1), two equivalent P(3), and two equivalent P(4) atoms to form NiP6 octahedra that share corners with two equivalent P(1)Ni2P2 tetrahedra, corners with four equivalent P(4)Ni2P2 tetrahedra, corners with four equivalent P(2)NiP3 tetrahedra, corners with four equivalent P(3)NiP3 tetrahedra, and edges with two equivalent Ni(2)P6 octahedra. Both Ni(1)-P(1) bond lengths are 2.43 Å. Both Ni(1)-P(3) bond lengths are 2.30 Å. Both Ni(1)-P(4) bond lengths are 2.29 Å. In the second Ni site, Ni(2) is bonded to two equivalent P(1), two equivalent P(2), and two equivalent P(4) atoms to form NiP6 octahedra that share corners with two equivalent P(4)Ni2P2 tetrahedra, corners with four equivalent P(1)Ni2P2 tetrahedra, corners with four equivalent P(2)NiP3 tetrahedra, corners with four equivalent P(3)NiP3 tetrahedra, and edges with two equivalent Ni(1)P6 octahedra. Both Ni(2)-P(1) bond lengths are 2.34 Å. Both Ni(2)-P(2) bond lengths are 2.27 Å. Both Ni(2)-P(4) bond lengths are 2.32 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one Ni(1), one Ni(2), one P(1), and one P(2) atom to form distorted PNi2P2 tetrahedra that share  a cornercorner with one Ni(1)P6 octahedra, corners with two equivalent Ni(2)P6 octahedra, corners with two equivalent P(1)Ni2P2 tetrahedra, corners with two equivalent P(4)Ni2P2 tetrahedra, corners with three equivalent P(3)NiP3 tetrahedra, corners with four equivalent P(2)NiP3 tetrahedra, and  an edgeedge with one P(4)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 56-67°. The P(1)-P(1) bond length is 2.21 Å. The P(1)-P(2) bond length is 2.30 Å. In the second P site, P(2) is bonded to one Ni(2), one P(1), one P(2), and one P(3) atom to form distorted PNiP3 tetrahedra that share corners with two equivalent Ni(1)P6 octahedra, corners with two equivalent Ni(2)P6 octahedra,  a cornercorner with one P(2)NiP3 tetrahedra, corners with two equivalent P(3)NiP3 tetrahedra, corners with three equivalent P(4)Ni2P2 tetrahedra, and corners with four equivalent P(1)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 54-75°. The P(2)-P(2) bond length is 2.21 Å. The P(2)-P(3) bond length is 2.26 Å. In the third P site, P(3) is bonded to one Ni(1), one P(2), one P(3), and one P(4) atom to form distorted PNiP3 tetrahedra that share corners with two equivalent Ni(1)P6 octahedra, corners with two equivalent Ni(2)P6 octahedra,  a cornercorner with one P(3)NiP3 tetrahedra, corners with two equivalent P(2)NiP3 tetrahedra, corners with three equivalent P(1)Ni2P2 tetrahedra, and corners with four equivalent P(4)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 59-65°. The P(3)-P(3) bond length is 2.24 Å. The P(3)-P(4) bond length is 2.23 Å. In the fourth P site, P(4) is bonded to one Ni(1), one Ni(2), one P(3), and one P(4) atom to form distorted PNi2P2 tetrahedra that share  a cornercorner with one Ni(2)P6 octahedra, corners with two equivalent Ni(1)P6 octahedra, corners with two equivalent P(1)Ni2P2 tetrahedra, corners with two equivalent P(4)Ni2P2 tetrahedra, corners with three equivalent P(2)NiP3 tetrahedra, corners with four equivalent P(3)NiP3 tetrahedra, and  an edgeedge with one P(1)Ni2P2 tetrahedra. The corner-sharing octahedral tilt angles range from 51-68°. The P(4)-P(4) bond length is 2.32 Å.