Eu2TlCl5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 8-coordinate geometry to two equivalent Cl(2), two equivalent Cl(3), two equivalent Cl(4), and two equivalent Cl(5) atoms. In the second Eu site, Eu(2) is bonded to one Cl(2), one Cl(3), one Cl(4), two equivalent Cl(1), and two equivalent Cl(5) atoms to form distorted edge-sharing EuCl7 pentagonal bipyramids. Tl(1) is bonded in a 1-coordinate geometry to two equivalent Cl(1) atoms. There are five inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 4-coordinate geometry to two equivalent Eu(2) and two equivalent Tl(1) atoms. In the second Cl site, Cl(2) is bonded in a distorted T-shaped geometry to one Eu(2) and two equivalent Eu(1) atoms. In the third Cl site, Cl(3) is bonded in a distorted trigonal non-coplanar geometry to one Eu(2) and two equivalent Eu(1) atoms. In the fourth Cl site, Cl(4) is bonded in a distorted trigonal non-coplanar geometry to one Eu(2) and two equivalent Eu(1) atoms. In the fifth Cl site, Cl(5) is bonded to two equivalent Eu(1) and two equivalent Eu(2) atoms to form a mixture of distorted corner and edge-sharing ClEu4 tetrahedra.
Eu2TlCl5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 8-coordinate geometry to two equivalent Cl(2), two equivalent Cl(3), two equivalent Cl(4), and two equivalent Cl(5) atoms. There is one shorter (2.98 Å) and one longer (3.07 Å) Eu(1)-Cl(2) bond length. There is one shorter (2.95 Å) and one longer (3.02 Å) Eu(1)-Cl(3) bond length. Both Eu(1)-Cl(4) bond lengths are 2.97 Å. There is one shorter (3.02 Å) and one longer (3.03 Å) Eu(1)-Cl(5) bond length. In the second Eu site, Eu(2) is bonded to one Cl(2), one Cl(3), one Cl(4), two equivalent Cl(1), and two equivalent Cl(5) atoms to form distorted edge-sharing EuCl7 pentagonal bipyramids. The Eu(2)-Cl(2) bond length is 2.92 Å. The Eu(2)-Cl(3) bond length is 2.98 Å. The Eu(2)-Cl(4) bond length is 3.00 Å. There is one shorter (2.86 Å) and one longer (2.92 Å) Eu(2)-Cl(1) bond length. Both Eu(2)-Cl(5) bond lengths are 2.92 Å. Tl(1) is bonded in a 1-coordinate geometry to two equivalent Cl(1) atoms. There is one shorter (3.12 Å) and one longer (3.22 Å) Tl(1)-Cl(1) bond length. There are five inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 4-coordinate geometry to two equivalent Eu(2) and two equivalent Tl(1) atoms. In the second Cl site, Cl(2) is bonded in a distorted T-shaped geometry to one Eu(2) and two equivalent Eu(1) atoms. In the third Cl site, Cl(3) is bonded in a distorted trigonal non-coplanar geometry to one Eu(2) and two equivalent Eu(1) atoms. In the fourth Cl site, Cl(4) is bonded in a distorted trigonal non-coplanar geometry to one Eu(2) and two equivalent Eu(1) atoms. In the fifth Cl site, Cl(5) is bonded to two equivalent Eu(1) and two equivalent Eu(2) atoms to form a mixture of distorted corner and edge-sharing ClEu4 tetrahedra.