Cs3PrCl6 crystallizes in the monoclinic C2/c space group. There are three inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to one Cl(1), one Cl(3), two equivalent Cl(2), two equivalent Cl(4), and two equivalent Cl(5) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Cl(2), one Cl(3), one Cl(4), one Cl(5), two equivalent Cl(1), and two equivalent Cl(6) atoms. In the third Cs site, Cs(3) is bonded in a 8-coordinate geometry to one Cl(1), one Cl(2), one Cl(4), one Cl(5), two equivalent Cl(3), and two equivalent Cl(6) atoms. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in an octahedral geometry to two equivalent Cl(2), two equivalent Cl(4), and two equivalent Cl(5) atoms. In the second Pr site, Pr(2) is bonded in an octahedral geometry to two equivalent Cl(1), two equivalent Cl(3), and two equivalent Cl(6) atoms. There are six inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 5-coordinate geometry to one Cs(1), one Cs(3), two equivalent Cs(2), and one Pr(2) atom. In the second Cl site, Cl(2) is bonded in a 5-coordinate geometry to one Cs(2), one Cs(3), two equivalent Cs(1), and one Pr(1) atom. In the third Cl site, Cl(3) is bonded in a 5-coordinate geometry to one Cs(1), one Cs(2), two equivalent Cs(3), and one Pr(2) atom. In the fourth Cl site, Cl(4) is bonded to one Cs(2), one Cs(3), two equivalent Cs(1), and one Pr(1) atom to form distorted face-sharing ClCs4Pr square pyramids. In the fifth Cl site, Cl(5) is bonded in a 5-coordinate geometry to one Cs(2), one Cs(3), two equivalent Cs(1), and one Pr(1) atom. In the sixth Cl site, Cl(6) is bonded in a 5-coordinate geometry to two equivalent Cs(2), two equivalent Cs(3), and one Pr(2) atom.
Cs3PrCl6 crystallizes in the monoclinic C2/c space group. There are three inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to one Cl(1), one Cl(3), two equivalent Cl(2), two equivalent Cl(4), and two equivalent Cl(5) atoms. The Cs(1)-Cl(1) bond length is 3.73 Å. The Cs(1)-Cl(3) bond length is 3.87 Å. There is one shorter (3.60 Å) and one longer (4.01 Å) Cs(1)-Cl(2) bond length. There is one shorter (3.67 Å) and one longer (3.68 Å) Cs(1)-Cl(4) bond length. There is one shorter (3.68 Å) and one longer (3.95 Å) Cs(1)-Cl(5) bond length. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Cl(2), one Cl(3), one Cl(4), one Cl(5), two equivalent Cl(1), and two equivalent Cl(6) atoms. The Cs(2)-Cl(2) bond length is 3.40 Å. The Cs(2)-Cl(3) bond length is 3.41 Å. The Cs(2)-Cl(4) bond length is 3.66 Å. The Cs(2)-Cl(5) bond length is 3.54 Å. There is one shorter (3.71 Å) and one longer (3.77 Å) Cs(2)-Cl(1) bond length. There is one shorter (3.57 Å) and one longer (3.58 Å) Cs(2)-Cl(6) bond length. In the third Cs site, Cs(3) is bonded in a 8-coordinate geometry to one Cl(1), one Cl(2), one Cl(4), one Cl(5), two equivalent Cl(3), and two equivalent Cl(6) atoms. The Cs(3)-Cl(1) bond length is 3.43 Å. The Cs(3)-Cl(2) bond length is 3.70 Å. The Cs(3)-Cl(4) bond length is 3.45 Å. The Cs(3)-Cl(5) bond length is 3.63 Å. There is one shorter (3.62 Å) and one longer (3.83 Å) Cs(3)-Cl(3) bond length. There is one shorter (3.44 Å) and one longer (3.47 Å) Cs(3)-Cl(6) bond length. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in an octahedral geometry to two equivalent Cl(2), two equivalent Cl(4), and two equivalent Cl(5) atoms. Both Pr(1)-Cl(2) bond lengths are 2.76 Å. Both Pr(1)-Cl(4) bond lengths are 2.78 Å. Both Pr(1)-Cl(5) bond lengths are 2.74 Å. In the second Pr site, Pr(2) is bonded in an octahedral geometry to two equivalent Cl(1), two equivalent Cl(3), and two equivalent Cl(6) atoms. Both Pr(2)-Cl(1) bond lengths are 2.78 Å. Both Pr(2)-Cl(3) bond lengths are 2.76 Å. Both Pr(2)-Cl(6) bond lengths are 2.78 Å. There are six inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 5-coordinate geometry to one Cs(1), one Cs(3), two equivalent Cs(2), and one Pr(2) atom. In the second Cl site, Cl(2) is bonded in a 5-coordinate geometry to one Cs(2), one Cs(3), two equivalent Cs(1), and one Pr(1) atom. In the third Cl site, Cl(3) is bonded in a 5-coordinate geometry to one Cs(1), one Cs(2), two equivalent Cs(3), and one Pr(2) atom. In the fourth Cl site, Cl(4) is bonded to one Cs(2), one Cs(3), two equivalent Cs(1), and one Pr(1) atom to form distorted face-sharing ClCs4Pr square pyramids. In the fifth Cl site, Cl(5) is bonded in a 5-coordinate geometry to one Cs(2), one Cs(3), two equivalent Cs(1), and one Pr(1) atom. In the sixth Cl site, Cl(6) is bonded in a 5-coordinate geometry to two equivalent Cs(2), two equivalent Cs(3), and one Pr(2) atom.