PrNi3 crystallizes in the trigonal R-3m space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 12-coordinate geometry to three equivalent Ni(3) and nine equivalent Ni(1) atoms. In the second Pr site, Pr(2) is bonded in a 18-coordinate geometry to six equivalent Ni(2) and twelve equivalent Ni(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Pr(2), three equivalent Pr(1), one Ni(3), two equivalent Ni(2), and four equivalent Ni(1) atoms to form NiPr5Ni7 cuboctahedra that share corners with two equivalent Ni(3)Pr6Ni6 cuboctahedra, corners with fifteen equivalent Ni(1)Pr5Ni7 cuboctahedra, edges with eight equivalent Ni(1)Pr5Ni7 cuboctahedra, faces with three equivalent Ni(3)Pr6Ni6 cuboctahedra, and faces with eleven equivalent Ni(1)Pr5Ni7 cuboctahedra. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Pr(2) and six equivalent Ni(1) atoms. In the third Ni site, Ni(3) is bonded to six equivalent Pr(1) and six equivalent Ni(1) atoms to form NiPr6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Pr5Ni7 cuboctahedra, edges with six equivalent Ni(3)Pr6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Pr5Ni7 cuboctahedra.
PrNi3 crystallizes in the trigonal R-3m space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 12-coordinate geometry to three equivalent Ni(3) and nine equivalent Ni(1) atoms. All Pr(1)-Ni(3) bond lengths are 2.98 Å. There are six shorter (2.90 Å) and three longer (3.18 Å) Pr(1)-Ni(1) bond lengths. In the second Pr site, Pr(2) is bonded in a 18-coordinate geometry to six equivalent Ni(2) and twelve equivalent Ni(1) atoms. All Pr(2)-Ni(2) bond lengths are 2.90 Å. All Pr(2)-Ni(1) bond lengths are 3.19 Å. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Pr(2), three equivalent Pr(1), one Ni(3), two equivalent Ni(2), and four equivalent Ni(1) atoms to form NiPr5Ni7 cuboctahedra that share corners with two equivalent Ni(3)Pr6Ni6 cuboctahedra, corners with fifteen equivalent Ni(1)Pr5Ni7 cuboctahedra, edges with eight equivalent Ni(1)Pr5Ni7 cuboctahedra, faces with three equivalent Ni(3)Pr6Ni6 cuboctahedra, and faces with eleven equivalent Ni(1)Pr5Ni7 cuboctahedra. The Ni(1)-Ni(3) bond length is 2.58 Å. There is one shorter (2.43 Å) and one longer (2.45 Å) Ni(1)-Ni(2) bond length. There are two shorter (2.50 Å) and two longer (2.52 Å) Ni(1)-Ni(1) bond lengths. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Pr(2) and six equivalent Ni(1) atoms. In the third Ni site, Ni(3) is bonded to six equivalent Pr(1) and six equivalent Ni(1) atoms to form NiPr6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Pr5Ni7 cuboctahedra, edges with six equivalent Ni(3)Pr6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Pr5Ni7 cuboctahedra.