Rare-earth chalcogenidotetrachloride clusters (RE3ECl4, RE = Dy, Gd, Y; E = S, Se, Te): syntheses and materials properties

Abstract

Rare-earth-containing materials featuring rare-earth–chalcogen (RE–E) coordination are of interest as optical and magnetic materials with enhanced properties over their counterparts with O-coordination. Herein, a series of rare-earth chalcogenidotetrachloride complexes of the general formula [η⁵-Cp*RE(μ-Cl)(THF)]₃(μ₃-Cl)(μ₃-E) (RE₃ECl₄: RE = Dy, Gd, Y; E = S, Se, Te; Cp* = pentamethylcyclopentadienide) were reported. Apart from for the identity of the rare-earth and chalcogen elements, these clusters share a common core motif composed of triangularly arranged RE atoms with one chloro ligand bridging each neighboring pair of RE atoms; the trimetallic plane is additionally capped by triply bridging chloro and chalcogenide ligands, one for each kind. Each RE atom is further coordinated with one Cp* and one THF ligand. Comparative magnetic and luminescence studies revealed fine but definitive differences due to using different metal and chalcogen elements. Experimental and computational studies have been used to gain insights into the dipolar and super-exchange interactions for the magnetically active Dy- and Gd-based clusters.