Pr3(TaN3)2 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to four equivalent N(1) and five equivalent N(2) atoms. In the second Pr site, Pr(2) is bonded in a body-centered cubic geometry to eight equivalent N(1) atoms. Ta(1) is bonded to one N(2) and four equivalent N(1) atoms to form corner-sharing TaN5 square pyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded to two equivalent Pr(1), two equivalent Pr(2), and two equivalent Ta(1) atoms to form a mixture of distorted edge, face, and corner-sharing NPr4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 0-65°. In the second N site, N(2) is bonded in a 6-coordinate geometry to five equivalent Pr(1) and one Ta(1) atom.
Pr3(TaN3)2 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to four equivalent N(1) and five equivalent N(2) atoms. All Pr(1)-N(1) bond lengths are 2.76 Å. There is one shorter (2.42 Å) and four longer (2.89 Å) Pr(1)-N(2) bond lengths. In the second Pr site, Pr(2) is bonded in a body-centered cubic geometry to eight equivalent N(1) atoms. All Pr(2)-N(1) bond lengths are 2.65 Å. Ta(1) is bonded to one N(2) and four equivalent N(1) atoms to form corner-sharing TaN5 square pyramids. The Ta(1)-N(2) bond length is 1.94 Å. All Ta(1)-N(1) bond lengths are 2.05 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded to two equivalent Pr(1), two equivalent Pr(2), and two equivalent Ta(1) atoms to form a mixture of distorted edge, face, and corner-sharing NPr4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 0-65°. In the second N site, N(2) is bonded in a 6-coordinate geometry to five equivalent Pr(1) and one Ta(1) atom.