Search results for "Manganese"
showing 10 items of 666 documents
Reversible Solvatomagnetic Switching in a Spongelike Manganese(II)-Copper(II) 3D Open Framework with a Pillared Square/Octagonal Layer Architecture
2012
The concept of "molecular magnetic sponges" was introduced for the first time in 1999 by the creative imagination of the late Olivier Kahn. It refers to the exotic spongelike behavior of certain molecule-based materials that undergo a dramatic change of their magnetic properties upon reversible dehydration/rehydration processes. Here we report a unique example of a manganese(II)-copper(II) mixed-metal-organic framework of formula [Na(H(2)O)(4)](4)[Mn(4){Cu(2)(mpba)(2)(H(2)O)(4)}(3)]·56.5H(2)O (1) (mpba=N,N'-1,3-phenylenebis(oxamate)). Compound 1 possesses a 3D Mn(II)(4)Cu(II)(6) pillared layer structure with mixed square and octagonal pores of approximate dimensions 1.2×1.2 nm and 2.1×3.0 n…
Field-Induced Hysteresis and Quantum Tunneling of the Magnetization in a Mononuclear Manganese(III) Complex
2013
International audience
Electronic and Magnetic Study of Polycationic Mn-12 Single-Molecule Magnets with a Ground Spin State S=11
2010
International audience; The preparation, magnetic characterization, and X-ray structures of two polycationic Mn-12 single-molecule magnets (Mn12O12(bet)(16)(EtOH)(4)](PF6)(14)center dot 4CH(3)CN center dot H2O (1) and [Mn12O12(bet)(16)(EtOH)(3)(H2O)](PF6)(13)(OH)center dot 6CH(3)CN center dot EtOH center dot H2O (2) (bet = betaine = (CH3)(3)N+-CH2-CO2-) are reported. 1 crystallizes in the centrosymmetric P2/cspace group and presents a (0:2:0:2) arrangement of the EtOH molecules in its structure. 2 crystallizes in the noncentrosymmetric P (4) over bar space group with two distinct Mn-12 polycations, [Mn12O12(bet)(16)(EtOH)(2)(H2O)(2)](14+) (2A) and [Mn12O12(bet)(16)(EtOH)(4)](14+)(2B) per un…
Electrochemistry of Bis(pyridine)cobalt (Nitrophenyl)corroles in Nonaqueous Media
2018
International audience; A series of bis(pyridine)cobalt corroles with one or three nitrophenyl groups on the meso positions of the corrole macrocycle were synthesized and characterized as to their electrochemical and spectroscopic properties in dichloromethane, benzonitrile, and pyridine. The potentials for each electrode reaction were measured by cyclic voltammetry and the electron-transfer mechanisms evaluated by analysis of the electrochemical data combined with UV-visible spectra of the neutral, electroreduced, and electroxidized forms of the corroles. The proposed electronic configurations of the initial compounds and the prevailing redox reactions involving the electroactive central c…
Tuning the Basicity of Synergic Bimetallic Reagents: Switching the Regioselectivity of the Direct Dimetalation of Toluene from 2,5‐ to 3,5‐Positions
2008
Meta-meta metalation: Remarkably, toluene can be directly dimanganated or dimagnesiated at the 3,5-positions using bimetallic bases with active Me3SiCH2 ligands (see scheme, blue). In contrast, n-butyl ligands lead to 2,5-metalation (red). tmp=2,2,6,6-tetramethylpiperidide.
COBALT SUBSTITUTED PROTEINS
1995
Cobalt(II) has been extensively used as a spectroscopic probe in many proteins, mainly replacing zinc, but also substituting iron, manganese and copper ions. The relatively short electronic relaxation times of high spin cobalt(II) makes this ion suitable as a paramagnetic probe for Nuclear Magnetic Resonance spectroscopy. A survey of the NMR studies performed in cobalt substituted proteins is shown. In the zinc enzymes Carboxypeptidase A, Carbonic Anhydrase and Superoxide Dismutase the implications of these studies on their catalytic mechanisms are commented. Finally, a further insight in the research of the blue copper protein Azurin by applying NMR to its cobalt derivative is also reporte…
CCDC 829874: Experimental Crystal Structure Determination
2012
Related Article: R.Inglis, E.Houton, Junjie Liu, A.Prescimone, J.Cano, S.Piligkos, S.Hill, L.F.Jones, E.K.Brechin|2011|Dalton Trans.|40|9999|doi:10.1039/c1dt11118c
CCDC 1057506: Experimental Crystal Structure Determination
2015
Related Article: Ian S. Morgan, Akseli Mansikkamäki, Georgia A. Zissimou, Panayiotis A. Koutentis, Mathieu Rouzières, Rodolphe Clérac and Heikki M. Tuononen|2015|Chem.-Eur.J.|21|15843|doi:10.1002/chem.201501343
CCDC 725617: Experimental Crystal Structure Determination
2009
Related Article: E.Coronado, C.Gimenez-Saiz, F.M.Romero, A.Tarazon|2009|Inorg.Chem.|48|2205|doi:10.1021/ic802218j
CCDC 2008124: Experimental Crystal Structure Determination
2020
Related Article: Sayantan Ganguly, Júlia Mayans, Ashutosh Ghosh|2020|Chem.Asian J.|15|4055|doi:10.1002/asia.202000706