Molecules containing rare-earth atoms solely bonded by transition metals.

Although metal-metal bonding is important in the chemistry of both solid-state intermetallic compounds and molecular species, the study of this bonding is limited by the compounds available and it is rarely possible to identify connections between these two areas. In this study, molecular intermetalloids [Ln(ReCp(2))(3)] (Ln = Sm, Lu and La) have been synthesized that contain lanthanoid metals bound only to transition metals. Although they are highly reactive species, such lanthanoid-core transition-metal-shell compounds can be stable in solution. They mimic the bonding situation of intermetallic compounds, as revealed by a direct comparison of molecular and solid state lanthanoid-transition metal bonding.