Pr4C2Br5 crystallizes in the monoclinic Cm space group. There are four inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(2), one Br(2), one Br(4), and two equivalent Br(3) atoms. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(2), one Br(1), one Br(5), and two equivalent Br(3) atoms. In the third Pr site, Pr(3) is bonded to one C(2), one Br(5), two equivalent Br(1), and two equivalent Br(4) atoms to form distorted edge-sharing PrCBr5 octahedra. In the fourth Pr site, Pr(4) is bonded to one C(1), one Br(4), two equivalent Br(2), and two equivalent Br(5) atoms to form distorted edge-sharing PrCBr5 octahedra. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to one Pr(4), two equivalent Pr(1), two equivalent Pr(2), and one C(2) atom. In the second C site, C(2) is bonded in a 6-coordinate geometry to one Pr(3), two equivalent Pr(1), two equivalent Pr(2), and one C(1) atom. There are five inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted T-shaped geometry to one Pr(2) and two equivalent Pr(3) atoms. In the second Br site, Br(2) is bonded in a distorted T-shaped geometry to one Pr(1) and two equivalent Pr(4) atoms. In the third Br site, Br(3) is bonded in a square co-planar geometry to two equivalent Pr(1) and two equivalent Pr(2) atoms. In the fourth Br site, Br(4) is bonded in a see-saw-like geometry to one Pr(1), one Pr(4), and two equivalent Pr(3) atoms. In the fifth Br site, Br(5) is bonded in a distorted see-saw-like geometry to one Pr(2), one Pr(3), and two equivalent Pr(4) atoms.
Pr4C2Br5 crystallizes in the monoclinic Cm space group. There are four inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(2), one Br(2), one Br(4), and two equivalent Br(3) atoms. Both Pr(1)-C(1) bond lengths are 2.69 Å. Both Pr(1)-C(2) bond lengths are 2.70 Å. The Pr(1)-Br(2) bond length is 3.09 Å. The Pr(1)-Br(4) bond length is 3.19 Å. Both Pr(1)-Br(3) bond lengths are 3.16 Å. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(2), one Br(1), one Br(5), and two equivalent Br(3) atoms. Both Pr(2)-C(1) bond lengths are 2.70 Å. Both Pr(2)-C(2) bond lengths are 2.69 Å. The Pr(2)-Br(1) bond length is 3.09 Å. The Pr(2)-Br(5) bond length is 3.18 Å. Both Pr(2)-Br(3) bond lengths are 3.16 Å. In the third Pr site, Pr(3) is bonded to one C(2), one Br(5), two equivalent Br(1), and two equivalent Br(4) atoms to form distorted edge-sharing PrCBr5 octahedra. The Pr(3)-C(2) bond length is 2.28 Å. The Pr(3)-Br(5) bond length is 3.30 Å. Both Pr(3)-Br(1) bond lengths are 2.98 Å. Both Pr(3)-Br(4) bond lengths are 3.05 Å. In the fourth Pr site, Pr(4) is bonded to one C(1), one Br(4), two equivalent Br(2), and two equivalent Br(5) atoms to form distorted edge-sharing PrCBr5 octahedra. The Pr(4)-C(1) bond length is 2.28 Å. The Pr(4)-Br(4) bond length is 3.30 Å. Both Pr(4)-Br(2) bond lengths are 2.98 Å. Both Pr(4)-Br(5) bond lengths are 3.05 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to one Pr(4), two equivalent Pr(1), two equivalent Pr(2), and one C(2) atom. The C(1)-C(2) bond length is 1.40 Å. In the second C site, C(2) is bonded in a 6-coordinate geometry to one Pr(3), two equivalent Pr(1), two equivalent Pr(2), and one C(1) atom. There are five inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted T-shaped geometry to one Pr(2) and two equivalent Pr(3) atoms. In the second Br site, Br(2) is bonded in a distorted T-shaped geometry to one Pr(1) and two equivalent Pr(4) atoms. In the third Br site, Br(3) is bonded in a square co-planar geometry to two equivalent Pr(1) and two equivalent Pr(2) atoms. In the fourth Br site, Br(4) is bonded in a see-saw-like geometry to one Pr(1), one Pr(4), and two equivalent Pr(3) atoms. In the fifth Br site, Br(5) is bonded in a distorted see-saw-like geometry to one Pr(2), one Pr(3), and two equivalent Pr(4) atoms.