Lanthanide Compounds with Fluorinated Aryloxide Ligands: Near-Infrared Emission from Nd, Tm, and Er

Ln(OC₆F₅)₃ form stable, isolable compounds with 1,2-dimethoxyethane (DME). Monomeric (DME)₂Ln(OC₆F₅)₃ (Ln = Nd, Er, Tm) adopt seven coordinate structures with two chelating DME and three terminal phenoxide ligands. Both (py)₄Er(OC₆F₅)₃ and (THF)₃Yb(OC₆F₅)₃ were also prepared and structurally characterized, with the latter being a mer-octahedral compound with bond lengths that are geometry dependent. Emission experiments on crystalline powders of the Nd(III), Tm(III), and Er(III) DME derivatives show that these compounds are highly emissive near-infrared sources.