Two different coordination geometries in polynuclear manganese(II) complexes with bis(μ-phosphinato) bridges

Covalent linkage of [Mn2(μ-O2PPh2)2] units by trans-1,4-bis(4-pyridyl)ethene ligands into one-dimensional and two-dimensional polymers

Two coordination polymers, [Mn2(μ-O2PPh2)2(η 1-O2PPh2)2(η 1-HOCH3)2(μ-bpe)2·CH3OH] n (1) and [Mn2(μ-O2PPh2)4(μ-bpe)2] n (2), were assembled in single-pot reactions from [Mn(CH3COO)2·4H2O], Ph2P(O)OK and trans-1,4-bis(4-pyridyl)ethene (bpe). The products were characterized by single-crystal X-ray diffraction, which revealed a one-dimensional metal-organic ladder type in 1 and a two-dimensional rectangular grid type in 2. Both 1 and 2 are constructed from six-coordinate Mn(II) nodes that adopt distorted octahedral (MnN4O2) environments; the adjacent nodes are connected by the μ-bpe linkers in 1 or μ-bpe and μ-O2PPh2 linkers in 2 to form different metal-organic networks. The catalytic property of complex 1 for selective thioether oxidation was also investigated in this work.

Toward an automated analysis of exchange pathways in spin-coupled systems

Understanding (super-)exchange coupling between local spins is an important task in theoretical chemistry and solid-state physics. We show that a Green's-function approach introduced earlier (Liechtenstein et al., J. Phys. F 1984, 14, L125; Steenbock et al., J. Chem. Theory Comput. 2015, 11, 5651) can be used for analyzing exchange coupling pathways in an automated fashion rather than by visual inspection of molecular orbitals. We demonstrate the capabilities of this approach by comparing it to previously published pathway analyses for hydroxy-bridged dinuclear copper complexes and an oxo-bridged dinuclear manganese complex, and employ it for discriminating between through-space and through-bond pathways in a naphthalene-bridged bisnickelocene complex. © 2017 Wiley Periodicals, Inc.