Overlay of X-ray structures of 1a (solid lines) and 1 (dashed lines). For clarity, the atoms of 1a were drawn as spheres to the 25% probability level and the atoms of 1 were drawn as small dots. Hydrogen atoms were omitted in both structures. The rmsd between the Sc, μ-O, Fe, and all non-hydrogen TMC atoms was found to be 0.0742 Å and is illustrated by the small deviation in bonds drawn above. The crystallographic R-factor (R1) is 0.0791, and complete XRD experimental and refinement details are reported in the SI.