Body-wing swapping in butterfly {Fe(III)2Ln(III)2} coordination clusters with triethylene glycol as ligand.

The first use of triethylene glycol (H(2)teg) in Fe/Ln chemistry affords two series of tetranuclear {Fe(III)(2)Ln(III)(2)} coordination clusters possessing defect-dicubane cores. A change in the synthetic procedure results in a different arrangement of the relative positions of the 3d and 4f elements offering a means to steer the structural and electronic features within a 3d-4f system.