Eu5B3O9Cl crystallizes in the orthorhombic C222_1 space group. There are four inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(4), two equivalent O(5), and two equivalent Cl(1) atoms. In the second Eu site, Eu(2) is bonded in a 8-coordinate geometry to one O(2), one O(3), two equivalent O(4), two equivalent O(5), and two equivalent Cl(1) atoms. In the third Eu site, Eu(3) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the fourth Eu site, Eu(4) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(5) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1) and two equivalent O(4) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Eu(1), two equivalent Eu(3), two equivalent Eu(4), and one B(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Eu(1), one Eu(2), one Eu(3), one Eu(4), and one B(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Eu(2), one Eu(3), one Eu(4), and one B(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Eu(1), one Eu(3), one Eu(4), two equivalent Eu(2), and one B(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Eu(1), two equivalent Eu(2), and one B(1) atom. Cl(1) is bonded in a 6-coordinate geometry to two equivalent Eu(1) and four equivalent Eu(2) atoms.
Eu5B3O9Cl crystallizes in the orthorhombic C222_1 space group. There are four inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(4), two equivalent O(5), and two equivalent Cl(1) atoms. The Eu(1)-O(1) bond length is 2.54 Å. Both Eu(1)-O(2) bond lengths are 2.89 Å. Both Eu(1)-O(4) bond lengths are 2.59 Å. Both Eu(1)-O(5) bond lengths are 2.58 Å. Both Eu(1)-Cl(1) bond lengths are 3.13 Å. In the second Eu site, Eu(2) is bonded in a 8-coordinate geometry to one O(2), one O(3), two equivalent O(4), two equivalent O(5), and two equivalent Cl(1) atoms. The Eu(2)-O(2) bond length is 2.65 Å. The Eu(2)-O(3) bond length is 2.48 Å. There is one shorter (2.62 Å) and one longer (3.01 Å) Eu(2)-O(4) bond length. There is one shorter (2.41 Å) and one longer (2.58 Å) Eu(2)-O(5) bond length. There is one shorter (2.89 Å) and one longer (3.22 Å) Eu(2)-Cl(1) bond length. In the third Eu site, Eu(3) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Both Eu(3)-O(1) bond lengths are 2.69 Å. Both Eu(3)-O(2) bond lengths are 2.69 Å. Both Eu(3)-O(3) bond lengths are 2.49 Å. Both Eu(3)-O(4) bond lengths are 2.84 Å. In the fourth Eu site, Eu(4) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Both Eu(4)-O(1) bond lengths are 2.72 Å. Both Eu(4)-O(2) bond lengths are 2.59 Å. Both Eu(4)-O(3) bond lengths are 2.61 Å. Both Eu(4)-O(4) bond lengths are 2.87 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(5) atom. The B(1)-O(2) bond length is 1.40 Å. The B(1)-O(3) bond length is 1.39 Å. The B(1)-O(5) bond length is 1.38 Å. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1) and two equivalent O(4) atoms. The B(2)-O(1) bond length is 1.40 Å. Both B(2)-O(4) bond lengths are 1.38 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Eu(1), two equivalent Eu(3), two equivalent Eu(4), and one B(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Eu(1), one Eu(2), one Eu(3), one Eu(4), and one B(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Eu(2), one Eu(3), one Eu(4), and one B(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Eu(1), one Eu(3), one Eu(4), two equivalent Eu(2), and one B(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Eu(1), two equivalent Eu(2), and one B(1) atom. Cl(1) is bonded in a 6-coordinate geometry to two equivalent Eu(1) and four equivalent Eu(2) atoms.