title: Metal-Metal Single Bonds with the Magnetic Anisotropy of Quadruple Bonds: A Systematic Series of Heterobimetallic Bismuth(II)-Rhodium(II) Formamidinate Complexes.
abstract: The first set of five heterobimetallic MM'(form)4(form=formamidinate) complexes containing a BiRh core has been successfully synthesized. The Bi-Rh bond lengths lie between 2.5196(6) and 2.572(2) Å, consistent with Bi-Rh single bonds. All complexes have rich electrochemistry, with the [BiRh]4+/5+redox couples spanning approximately 700 mV and showing a strong correlation to remote ligand substitution. Visible spectroscopy showed two features for complexes 1-5 at approximately 459 and 551 nm, unique to BiRh paddlewheel complexes that are attributed to LMCT bands into the Bi-Rh σ* orbital. The large spin-orbit coupling (SOC) of Bi creates a massive Bi-Rh magnetic anisotropy, Δχ, approximately -4800×10-36m3molecule-1, which is the largest value reported for any single bond to date.
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave. Madison, WI, 53706, USA.
authors.forename: Travis L
authors.initials: TL
authors.lastname: Sunderland
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave. Madison, WI, 53706, USA.
authors.forename: John F
authors.initials: JF
authors.lastname: Berry
keywords: bismuth; heterobimetallic complexes; magnetic anisotropy; metal-metal bonds; rhodium