Halogen Oxidation of Tetrakis(dithioacetato)diplatinum(II) Complexes, Pt2(CH3CS2)4.Synthesis and Characterization of Pt2(CH3CS2)4X2 (X = Cl, Br, I) and Structural, Electrical, and Optical Properties of Linear-Chain (ju-Iodo)tetrakis(dithioacetato)diplatinum, Pt2(CH3CS2)4I

Several doped spinel-type Li-Mn oxides of formula Li 1+x M y Mn 2-(x+y) O 4+z , where Mn is partly replaced by Li, Cu, Zn, Ni, Co, Fe, Cr, Ga, Al, B, or Ti, were prepared by a solid-state reaction at 730°C. These spinels were investigated by X-ray powder diffraction, thermal analysis, slow step voltammetry, and galvanostatic cycling at medium-high rates. Even substitutional levels as low as 0.05 atom/formula unit produce structural effects that are reflected in the electrochemical characteristics. The substituents may occupy either tetrahedral 8a sites or octahedral 16d sites. Examples of the first type of substitution are provided by Ga 3+ and Zn 2+ , while octahedral sites are preferred by, e.g., Ni 2+ and Cr 3+ . Cycling at practical rates produces capacities of ∼100 mA h/g for the best materials with limited capacity losses (3-6‚10 -2 mA h/g‚cycle). The lower Mn 3+ content with respect to undoped spinel explains the initially lower capacities.

In the salt formed by bis͑ethylenedithio͒tetrathiafulvalene ͑BEDT-TTF͒ with the ͓Mo 6 O 19 ͔ 2Ϫ anion, the BEDT-TTF ϩ cations form quasi-isolated dimers. For this reason (BEDT-TTF͒ 2 Mo 6 O 19 has been selected to experimentally evaluate the BEDT-TTF ϩ microscopic parameters. Using the microreflectance technique we were able to collect polarized infrared/visible spectra from a single-crystal face. The analysis of the spectra in terms of the isolated dimer model yields reliable estimates of BEDT-TTF ϩ electron-molecular vibration (e-mv) coupling constants. The effective on-site electron-electron repulsion is also evaluated. A comparison is made with available theoretical estimates of e-mv coupling constants. The possible role of e-mv coupling in BEDT-TTF based superconductors is briefly discussed.

Die oxidative Addition von I2 an Tetrakis‐ [dithioacetatol]‐dinickel (I) führt zu dem linearen Kettenpolymeren (II), in dem der formale Oxidationszustand der Ni‐Atome + 2.5 beträgt.

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