ErC3O8 crystallizes in the orthorhombic P2_12_12_1 space group. Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are three inequivalent C sites. In the first C site, C(1) is bonded in a linear geometry to one O(1) and one O(2) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(3), one O(4), and one O(7) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Er(1) and one C(3) atom. In the second O site, O(6) is bonded in an L-shaped geometry to one Er(1) and one C(3) atom. In the third O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(2) atom. In the fourth O site, O(8) is bonded in an L-shaped geometry to one Er(1) and one C(3) atom. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to one Er(1) and one C(1) atom. In the sixth O site, O(2) is bonded in a distorted single-bond geometry to one Er(1) and one C(1) atom. In the seventh O site, O(3) is bonded in a single-bond geometry to one C(2) atom. In the eighth O site, O(4) is bonded in a linear geometry to one Er(1) and one C(2) atom.
ErC3O8 crystallizes in the orthorhombic P2_12_12_1 space group. Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. The Er(1)-O(1) bond length is 2.63 Å. The Er(1)-O(2) bond length is 2.61 Å. The Er(1)-O(4) bond length is 2.23 Å. The Er(1)-O(5) bond length is 2.15 Å. The Er(1)-O(6) bond length is 2.23 Å. The Er(1)-O(7) bond length is 2.25 Å. The Er(1)-O(8) bond length is 2.26 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a linear geometry to one O(1) and one O(2) atom. The C(1)-O(1) bond length is 1.17 Å. The C(1)-O(2) bond length is 1.17 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(3), one O(4), and one O(7) atom. The C(2)-O(3) bond length is 1.27 Å. The C(2)-O(4) bond length is 1.28 Å. The C(2)-O(7) bond length is 1.30 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(8) atom. The C(3)-O(5) bond length is 1.28 Å. The C(3)-O(6) bond length is 1.29 Å. The C(3)-O(8) bond length is 1.31 Å. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Er(1) and one C(3) atom. In the second O site, O(6) is bonded in an L-shaped geometry to one Er(1) and one C(3) atom. In the third O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(2) atom. In the fourth O site, O(8) is bonded in an L-shaped geometry to one Er(1) and one C(3) atom. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to one Er(1) and one C(1) atom. In the sixth O site, O(2) is bonded in a distorted single-bond geometry to one Er(1) and one C(1) atom. In the seventh O site, O(3) is bonded in a single-bond geometry to one C(2) atom. In the eighth O site, O(4) is bonded in a linear geometry to one Er(1) and one C(2) atom.