Octahedral erbium and ytterbium ion encapsulated in phosphorescent iridium complexes showing field-induced magnetization relaxation

Four isostructural heptanuclear clusters [LnIr6(ppy)12(bpp)2(bppH)4](CF3SO3)·xH2O (Ir6Ln, Ln = Eu, Tb, Er, Yb) are reported, where the lanthanide ions are six-coordinated by the phosphonate oxygen donors from six [Ir(ppy)2(bpp)] (ppy− = 2-phenylpyridine, bpp2− = 2-pyridylphosphonate) chromophores. All show phosphorescence originating from the IrIII moieties. For compounds Ir6Er and Ir6Yb, field-induced slow magnetization relaxation is also observed, thus providing the first examples of Ir-Er or Ir-Yb complexes showing bifunctional phosphorescence and field-induced single ion magnet behaviors.