Unimolecular decomposition of silane, fluorosilane, and difluorosilane at high temperatures
摘要:
The thermal decomposition of SiH4, SiH3F, and SiH2F2 diluted in AR was studied behind incident shock waves by monitoring Ir emission from these reactant molecules. The rate constants of the unimolecular decomposition for all of three molecules were found to be in the pressure falloff region over the present experimental conditions (T = 1190-2150 K and P = 0.2-1.6 atm). The activation energies of measured rate constants were compared with heats of reactions for the various possible pathways for the thermal decomposition of these molecules and it was concluded that three-center H-2 elimination reactions were the dominant pathways for unimolecular reactions of SiH4-n(F)n (n = 0, 1, and 2). These rate constants decrease with increasing number of fluorine atoms, n, in SiH4-n(F)n. RRKM falloff calculations have been performed to examine the effect of fluorine substitution on the unimolecular decomposition rates of these molecules.
Preparation and spectroscopic studies of some reactions of lithium derivatives of silanol, disilylphosphine, and related compounds
作者:Stephen Cradock、E. A. V. Ebsworth、David W. H. Rankin、W. John Savage
DOI:10.1039/dt9760001661
日期:——
reacts with Y(SiH3)2(Y = O, S, or Se) or Z(SiH3)3(Z = P or As) in diethyl ether to give Li(YSiH3) or Li[Z(SiH3)2]; these compounds have been characterised by i.r., Raman, and n.m.r. spectroscopy, and some of their reactionswith halides have been studied. Trisilylamine does not react cleanly with LiMe to form an analogous compound. The n.m.r. spectra of solutions containing both Li(YSiH3) and Y(SiH3)2
Preparation and properties of difluorophosphino(tetrafluorophosphoranyl)amine
作者:David W. H. Rankin、John G. Wright
DOI:10.1039/dt9790001070
日期:——
The compound NH(PF2)(PF4) has been prepared from PF2[NH(SiH3)] by reaction with PF5. Vibrational, photoelectron, n.m.r., and mass spectroscopic data have been recorded, and interpreted in terms of the probable structure and conformation of the molecule. At low temperatures the phosphorus(V) group has chemically equivalent equatorial fluorine atoms but non-equivalent axial atoms, indicating restricted
Preparation and chemical and spectroscopic properties of (disilylamino)difluorophosphine and bis(difluorophosphino)silylamine
作者:E. A. V. Ebsworth、David W. H. Rankin、John G. Wright
DOI:10.1039/dt9790001065
日期:——
N(PF2)2(SiH3) have been prepared by the reactions of SiBrH3 and NMe3 with PF2[NH(SiH3)] and NH(PF2)2 respectively. Vibrational, n.m.r., mass, and photoelectron spectra have been recorded, and chemicalproperties have been studied. With diborane, PF2[N(SiH3)2] gives the adduct PF2[N(SiH3)2]·BH3 and N(PF2)2(SiH3) gives both mono- and bis-(borane) adducts; n.m.r. spectre of the three borane adducts have
Reactions of silanes and germanes with iridium complexes. Part 4. Reactions with carbonylhydridotris(triphenylphosphine)iridium(I)
作者:E. A. V. Ebsworth、Thomas E. Fraser、Steven G. Henderson、Diana M. Leitch、David W. H. Rankin
DOI:10.1039/dt9810001010
日期:——
The title complex, [IrH(CO)(PPh3)3](1), reacts with MH3Q (M = Si or Ge when Q = H, F, Cl, Br, or I; M = Si when Q = SiH3 or CH3) to give [IrH2(CO)(PPh3)2(MH2Q)]. The products have been characterised by 1H, 31P, and (where appropriate)19F n.m.r. spectra. Where M = Ge, the predominant isomer contains mutually trans phosphine ligands, whereas when M = Si the predominant (and in some cases the sole) product