A series of 1,3,2,4,5-dithiadiazarsoles with the general formula RAs(S₂N₂) (R = Me, Et, i-Pr, t-Bu, Ph and Mes) have been prepared and characterised by multinuclear NMR, IR and Raman spectroscopies and mass spectrometry. The X-ray structures of PhAs(S₂N₂) and MesAs(S₂N₂) were determined. The low temperature X-ray structures of the half-sandwich 5,1,3,2,4-metalladithiadiazoles Cp*M(S₂N₂) (M = Co, Ir) were determined and Cp*Rh(S₂N₂) was prepared. All three metalladithiadiazoles were characterised by multinuclear NMR, IR and Raman spectroscopies and mass spectrometry. The X-ray structures of complexes [Cp*RhCp*]Cl,[Cp*Rh(μ-S₃N₂)(μ-S₂O₃)RhCp*] and Cp*Ir[S₂N₂(IrCl₂Cp*)] obtained during this work were determined. The low temperature X-ray structure of Roesky's sulfoxide (S₃N₂O) is presented together with assignments of its vibrational spectra as suggested by theoretical calculations. The experimental structures of the metalladithiadiazoles and that of Roesky's sulfoxide are compared with calculated geometries. A limited amount of simple experiments have been carried out with selected title compounds to get an insight into their reactivity.

科学研究費補助金 研究種目:基盤研究(B) 課題番号:17360336 研究代表者:金武 直幸 研究期間:2005-2007年度

Silicon-on-insulator is a key technology which ensures continuation of Moore’s law. This document investigates the impact of orientation, confinement, and strain on the electronic structure of thin silicon slabs using density functional theory. Moreover a systematic comparison of FDSOI device characteristics using parameters of both the default bulk material and that of the studied slab material is also performed. The comparative study of low index orientations show that confinement not only widens the band gap but also transforms the band gap type. Moreover, it is found that for thin silicon layers, strain can alter band gap and band gap type. By summarizing the findings for different crystal orientations, we demonstrate that the consideration of the electronic structure of strained and confined silicon is of high relevance for modelling actual devices with ultra thin body.