Organometallic lanthanide bismuth cluster single-molecule magnets

•Isolation of organometallic f-element bismuth cluster complexes•Heterometallocubane [Ln2Bi6] featuring two lanthanides bridged through a Bi66? unit•Single-molecule magnets containing donors•Magnetic hysteresis in superexchange-coupled lanthanide complexes Single-molecule are molecules that act as nanoscopic analogs to classical and have garnered substantial interest due their potential applications high-density information storage, magnetic refrigeration, spin-based electronics, quantum computation. To realize such applications, memory loss needs be prevented, which requires judicious design coordination complexes. Herein, we developed strategy unprecedented SMMs comprising ions exhibit memory. The core heterometallocubane includes was hitherto unknown. Despite the contracted nature 4f-orbitals, allows significant superexchange, thus defining new platform for SMM design. This peerless class compounds leads also prospects physics synthetic chemistry. (SMMs) can retain polarization absence an external field embody ultimate size limit storage processing. Multimetallic lacking exchange coupling enable fast relaxation pathways attenuate full these species. Employment diamagnetic heavy main group elements with diffuse orbitals may lead strong coupling. bismuth-cluster-bridged complexes, [K(THF)4]2[Cp?2Ln2Bi6] (Cp? = pentamethylcyclopentadienyl; 1-Ln, Ln Tb, Dy), were synthesized via solution approach. neutral features centers by rare Zintl ion, supports ferromagnetic interactions between lanthanides. affords observation blocking open loops solely ions. Both constitute first donors paving way promising targets Molecular magnetism is textbook example synergetic effects arising from interplay chemistry composes vibrant, multidisciplinary, established research field.1Gatteschi D. Sessoli R. Vallain J. Nanomagnets. 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Indeed, inferred involve increased consist elements.20Chen Scholar,32Lips For example, calculations protected]4Bi9]4? indicated delocalization free pair site empty dz2-orbital center.32Lips compressed body diagonal 4.043(1) 4.034(1) Dy average 5.632(1) 5.617(1) corresponding diagonally opposite Bi–Ln–Bi angles 101.02(2)°–102.19(2)° 101.06(2)°–102.45(2)° larger 90° angle ideal