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The mixed-metal cluster compound (PPh4)[Fe2Ir2(CO)12{μ3-Au(PPh3)}], which has a trigonal bipyramidal core consisting of five atoms of three different Mössbauer isotopes, was studied by 193Ir, 197Au and 57Fe Mössbauer spectroscopy. The nature and the chemical character of the atoms located at the different sites are discussed with respect to their Mössbauer spectra. [ABSTRACT FROM AUTHOR]

The mixed-metal cluster compound (PPh4)[Fe2Ir2(CO)12{μ3-Au(PPh3)}], which has a trigonal bipyramidal core consisting of five atoms of three different Mössbauer isotopes, was studied by 193Ir, 197Au and 57Fe Mössbauer spectroscopy. The nature and the chemical character of the atoms located at the different sites are discussed with respect to their Mössbauer spectra. [ABSTRACT FROM AUTHOR]

119Sn Mössbauer spectroscopy and X-ray diffraction were used to study the state of tin in opaque lead rich glazes, where small cassiterite (SnO2) particles serve as opacifiers. [ABSTRACT FROM AUTHOR]

We present the development of the Mössbauer method as applied to the investigation of archaeological artefacts in Italy from 1980 on. In this way, we attempt to demonstrate the gradual improvement of the results and their increasing usefulness to archaeologists. [ABSTRACT FROM AUTHOR]

Abstract: Commercial C-LiFe0.33Mn0.67PO4 positive electrode material has been investigated by 57Fe Mössbauer Spectroscopy (MS), X-ray Photoelectron Spectroscopy (XPS) and X-ray Absorption Spectroscopy (XAS). The combined use of these experimental techniques provides a better understanding of the electrochemical reaction involved during cycling. 57Fe MS is very efficient to directly follow oxidation state of Fe in the electrode, and gives surprisingly indirect information on the oxidation state of Mn as observed by XAS and XPS. The electrochemical mechanism is proposed based from in situ and operando investigations using both MS and XAS, and is consistent with XPS surface studies. XPS analysis of the electrodes at the end of charge (4.4V) reveals enhanced electrode/electrolyte interface reactivity at this high potential. Aging of C-LiFe0.33Mn0.67PO4/Li cells after 50cycles at 60°C indicates a rather good electrochemical behavior (low capacity fading) of the electrode material. Both 57Fe MS and XPS (Mn 2p and Fe 2p) clearly show no modification on Fe and Mn oxidation state compared to fresh electrode confirming the good electrochemical performances. [Copyright &y& Elsevier]

Abstract: The composite [Sn–BPO4/xC] to be used as negative electrode material for the storage of electrochemical energy was obtained by dispersing electroactive tin species onto a BPO4 buffer matrix by carbothermal reduction of a mixture of SnO2 and nanosized BPO4. This composite material was thoroughly characterized by X-ray diffraction, Scanning Electron Microscopy, 119Sn Mössbauer spectroscopy and Raman spectroscopy. The electrochemical tests of this new material highlight its very interesting electrochemical properties, i.e., a discharge capacity of 850mAhg−1 for the first cycle and reversible capacity around 585mAhg−1 at C/5 rate. These electrochemical performances are attributed to the very high dispersion and stabilisation of tin metal particles onto the BPO4 matrix. The irreversible capacity observed for the first charge/discharge cycle is due the reduction of interfacial SnII species and to the passivation of the anode surface by liquid electrolyte decomposition (formation of the SEI layer). [Copyright &y& Elsevier]