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The natural Mn4Ca cluster in photosystem II serves as a blueprint to develop artificial water‐splitting catalysts for the generation of solar fuel in artificial photosynthesis. Although significant advances have recently been achieved, it remains a great challenge to prepare robust artificial Mn4Ca clusters that precisely mimic the structure and function of the biological catalyst. Herein, we report the isolation and structural characterization of two Mn4CaO4 complexes with polar solvent molecules, acetonitrile or N,N‐dimethylformamide, which closely mimics the two water molecules on the calcium ion, as well as the oxidation states of the four manganese ions and the main geometric structure of the natural Mn4Ca cluster. These new artificial Mn4Ca complexes provide important chemical clues to understand the structure and mechanism of the biological system. [ABSTRACT FROM AUTHOR]

While the coordination chemistry of monometallic complexes and the surface properties of extended metal particles are well understood, the control of metal nanocluster formation has remained challenging. The isolation of discrete metal clusters provides an especially rare snapshot at the nanoscale of cluster growth. The synthesis and full characterization of the first early‐transition‐metal alkynyl cubane and the first μ3‐alkynyl Mn3 motif are reported. [ABSTRACT FROM AUTHOR]

Water electrolysis is among the simplest method for generating hydrogen as an alternative renewable fuel. A major challenge associated with this process is the development of cheap, simple, and environmentally benign catalysts that lead to a minimum overpotential for water oxidation. Inspired by the Mn4CaOx cluster that catalyzes water oxidation in photosystem II, described here is the synthesis and characterization of the manganese cluster [Mn12O12(O2CC6H2(OH)3)16(H2O)4] (Mn12TH) along with its electrocatalytic activity at pH 6. Electrochemical, spectroscopic, and electron microscopy studies show that Mn12TH is a homogeneous electrocatalyst for water oxidation and enables oxygen evolution with a reaction rate of 22 s−1, high Faradic efficiency (93 %), and an overpotential of only 74 mV, the lowest reported to date. Based on the electrochemical data, the organic ligands, which can be described as the second coordination sphere of the catalytic manganese core, play a key role in facilitating the oxidation process and accelerating the reaction. [ABSTRACT FROM AUTHOR]

The systematic exploration of the reactivity of [Mn(hfacac)2] with R-salicyloximes (R-saloxH2: R = H, Me, Et) yielded a family of clusters with nuclearities ranging from Mn4 to Mn12. The compounds with formula [Mn6(O)2(salox)6(CF3COO)2(EtOH)4] ( 1) and [Mn12(salox)12(O)4(N3)4(H2O)2(MeOH)6] ( 4) show two or four linked {Mn(µ3-O)(salox)3}+ triangular subunits. Magnetic measurements revealed spin ground states of S = 4 for 1 and S = 8 for 4, as well as single-molecule magnet responses and magnetic hysteresis above 2 K. The cubic [Mn4(Mesalox)4(MesaloxH)4] ( 2), the hexanuclear [Mn6(Etsalox)6(O)2(MeO)4(MeOH)2] ( 3) and the octanuclear [Mn8(Mesalox)6(O)2(N3)6(MeOH)8] ( 5) are polymorphs of previously reported systems. Small structural changes allows an S = 11 ground state for 3. [ABSTRACT FROM AUTHOR]

The systematic exploration of the reactivity of [Mn(hfacac)2] with R-salicyloximes (R-saloxH2: R = H, Me, Et) yielded a family of clusters with nuclearities ranging from Mn4 to Mn12. The compounds with formula [Mn6(O)2(salox)6(CF3COO)2(EtOH)4] ( 1) and [Mn12(salox)12(O)4(N3)4(H2O)2(MeOH)6] ( 4) show two or four linked {Mn(µ3-O)(salox)3}+ triangular subunits. Magnetic measurements revealed spin ground states of S = 4 for 1 and S = 8 for 4, as well as single-molecule magnet responses and magnetic hysteresis above 2 K. The cubic [Mn4(Mesalox)4(MesaloxH)4] ( 2), the hexanuclear [Mn6(Etsalox)6(O)2(MeO)4(MeOH)2] ( 3) and the octanuclear [Mn8(Mesalox)6(O)2(N3)6(MeOH)8] ( 5) are polymorphs of previously reported systems. Small structural changes allows an S = 11 ground state for 3. [ABSTRACT FROM AUTHOR]

A new Mn16 topology consisting of one hexanuclear {MnII2MnIII4} unit coordinated inside a decametallic {MnII6MnIII2MnIV2} wheel was synthesized from 2-pyridylcyanoxime and azido ligands. A new tetrazole-2-pyridylketoneoximate ligand was obtained in situ by cyclization of the cyano group and azide mediated by manganese cations. [ABSTRACT FROM AUTHOR]

The article presents abstracts on inorganic chemistry topics which include manganese clusters, photoactive porous silicon, and rare-earth imido complexes.

Rechargeable molecular-cluster batteries (MCBs) based on the manganese cluster complex [Mn12O12(CH3CH2C(CH3)2COO)16(H2O)4] ([Mn12]) that exhibited a capacity of approximately 200 A h kg−1 in the battery voltage range of 4.0 to 2.0 V were developed. In these batteries, the capacity of approximately 100 A h kg−1 in the range of 4.0-3.0 V is caused by a chemical reduction from [Mn12]0 to [Mn12]8−, whereas the other half in the range of 3.0-2.0 V cannot be explained by a redox change of the Mn ions. We performed the cyclic voltammetry (CV) and 7Li solid-state NMR measurements on the Mn12-MCBs to investigate the origin of the capacity below 3.0 V. Pseudo-rectangular-shaped CV curves in the range of 3.0-2.0 V demonstrate the presence of an electrical double-layer (EDL) capacitance in Mn12-MCBs, which corresponds to approximately 100 A h kg−1. 7Li NMR studies suggest that Li ions form an EDL with electrons in carbon black electrodes in the capacitance voltage range. The capacitance effects are not formed by the single-carbon electrodes alone, but appear only in the mixture of Mn12 and the carbon black electrodes. This type of coexistence of capacitance effects and redox reaction in one electrochemical cell is quite unusual and can serve as a new working principle for high-performance energy-storage devices. [ABSTRACT FROM AUTHOR]

The title dodecanuclear Mn complex, namely dodeca-μ2-acetato-κ24 O: O′-tetraaquatetra-μ2-nitrato-κ8 O: O′-tetra-μ4-oxido-octa-μ3-oxido-tetramanganese(IV)octamanganese(III) nitromethane tetrasolvate, [Mn12(CH3COO)12(NO3)4O12(H2O)4]·4CH3NO2, was synthesized by the reaction of Mn2+ and Ce4+ sources in nitromethane with an excess of acetic acid. This compound is distinct from the previously known single-molecule magnet [Mn12O12(O2CMe)16(H2O)4], synthesized by Lis [ Acta Cryst. (1980), B 36, 2042-2044]. It is the first Mn12-type molecule containing nitrate ligands to be directly synthesized without the use of a preformed cluster. Additionally, this molecule is distinct from all other known Mn12 complexes due to intermolecular hydrogen bonds between the nitrate and water ligands, which give rise to a three-dimensional network. The complex is compared to other known Mn12 molecules in terms of its structural parameters and symmetry. [ABSTRACT FROM AUTHOR]

Equimolar amounts of K7[HNb6O19]·13H2O and K12 [H2P2W12O48] ·24H2O are reacted in aq. [ABSTRACT FROM AUTHOR]

The article presents abstracts on topics related to materials science including the molecular and electronic structure changes of the molecular magnet Mn12 cluster, magnetic shape memory alloys, and nanoporous TiO2 films.