Reaction mechanisms and kinetics of the elimination processes of 2-chloroethylsilane and derivatives: A DFT study using CTST, RRKM, and BET theories

• Published in: Chemical physics Vol. 485-486; pp. 140 - 148
• Main Authors: Shiroudi, Abolfazl, Zahedi, Ehsan, Oliaey, Ahmad Reza, Deleuze, Michael S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2017
• Subjects: 2-Chloroethylsilane; Electron localization function; Elimination processes; Energy barriers; Molecular modelling; Rate constants; Reaction mechanisms; Elimination processes; Energy barriers; Molecular modelling; Rate constants; Electron localization function; Reaction mechanisms; 2-Chloroethylsilane
• ISSN: 0301-0104
• DOI: 10.1016/j.chemphys.2017.01.009

The thermal decomposition kinetics of 2-chloroethylsilane and derivatives in the gas phase has been studied computationally using density functional theory, along with various exchange-correlation functionals (UM06-2x and ωB97XD) and the aug-cc-pVTZ basis set. The calculated energy profile has been supplemented with calculations of kinetic rate constants under atmospheric pressure and in the fall-off regime, using transition state theory (TST) and statistical Rice–Ramsperger–Kassel–Marcus (RRKM) theory. Activation energies and rate constants obtained using the UM06-2x/aug-cc-pVTZ approach are in good agreement with the experimental data. The decomposition of 2-chloroethyltriethylsilane species into the related products [C2H4+Et3SiCl] is characterized by 6 successive structural stability domains associated to the sequence of catastrophes C8H19SiCl: 6-C†FCC†[FF]-0: C6H15SiCl+C2H4. Breaking of Si–C bonds and formation of Si–Cl bonds occur in the vicinity of the transition state.