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Sulphur dioxide reacts with 1-oxydienes generating zwitterions which are quenched by enoxysilanes to form substituted silyl alkenylsulfinates. These intermediates are desilylated with Bu4NF and the resulting sulfinates react with MeI giving the correspondi ...
Silicon dioxide (SiO2) films grown on silicon monocrystal (Si) substrates form the gate oxides in current Si-based microelectronics devices. The understanding at the atomic scale of both the silicon oxidation process and the properties of the Si(100)-SiO2 ...
After assessing the current status concerning the interpretation of Si 2p core-level shifts in Si-O systems, we model the atomic structure of the Si(001)-SiO2 interface using recent photoemission data obtained with synchrotron radiation. Our model structur ...
Using constrained ab initio molecular dynamics, we investigate the reaction of the O-2 molecule at the Si(100)-SiO2 interface during Si oxidation. The reaction proceeds sequentially through the incorporation of the O-2 molecule in a Si-Si bond and the diss ...
The correlation between Si-29 chemical shifts and Si-O-Si bond angles in SiO2 is determined within density-functional theory for the full range of angles present in vitreous silica. This relation closely reproduces measured shifts of crystalline polymorphs ...
Using a first-principles approach, we assess the validity of a picture for the energetics at Si-SiO2 interfaces based on bond energies complemented with penalty energies for silicon atoms in intermediate oxidation states. By total-energy calculations on cl ...
A model structure of vitreous silica, for which the vibrational frequencies and eigenmodes were calculated from first principles, is used to investigate vibrational amplitudes. Calculated mean-square displacements for oxygen and silicon atoms are obtained ...
We use mass-resolved 2+2 resonantly enhanced multiphoton ionization (REMPD of silicon atoms to detect isotopically selective infrared multiphoton dissociation (IRMPD) of both ground-state and vibrationally pre-excited SiH4. To demonstrate that the detectio ...
Syntheses of thermally stable chromium-incorporating hexagonal mesoporous aluminophosphate and cubic Cr-MCM-48 were reported. Characterization of the catalysts was made using low angle XRD, N2 adsorption, UV-VISDRS, thermal anal., ICP-AES and ESR. Mesoporo ...
The HH and HV Raman spectra of vitreous silica are calculated from first principles for a model structure consisting of a disordered network of corner-sharing tetrahedra, for which the vibrational properties were obtained previously. We analyse the contrib ...
