African Journal of
Pure and Applied Chemistry

  • Abbreviation: Afr. J. Pure Appl. Chem.
  • Language: English
  • ISSN: 1996-0840
  • DOI: 10.5897/AJPAC
  • Start Year: 2007
  • Published Articles: 357

Full Length Research Paper

Ab-initio and DFT studies of the kinetics, mechanisms and thermodynamics of the gas-phase pyrolysis of ethyl bromide

I. A. Adejoro
  • I. A. Adejoro
  • Department of Chemistry, University of Ibadan, Nigeria
  • Google Scholar
O. O. Adeboye
  • O. O. Adeboye
  • Department of Chemistry, Emmanuel Alayande College of Education, Oyo
  • Google Scholar
T. Esan
  • T. Esan
  • Department of Chemistry, University of Ibadan, Nigeria
  • Google Scholar


  •  Accepted: 20 May 2013
  •  Published: 30 June 2013

Abstract

The kinetics, mechanisms, thermodynamics and vibrational studies of the pyrolysis of ethyl bromide in the gas – phase at 623 K was studied using HF at 3-21G, 6-31G* and DFT with B3LYP/6 31G*, 6-311++G (2df, 2p) basis sets. The reaction proved to be a unimolecular reaction and followed a first order rate equation. The Arrhenius parameters, such as log A with HF at 3-21G, 6-31G* = 13.93, 13.86; DFT/B3LYP at 6-31G*, 6-311++G (2df, 2p) levels = 13.61, 13.97, Ea = 228.25, 220.308 kJ/mol, ∆H = 223.25, 215.25 kJ/mol, ∆S = 14.27, 20.92 J/mol.K, ∆G = 208.99, 194.46 kJ/mol and K = 1.1 × 10-5, 5.2 × 10-5 S­-1respectively are in good agreement with the experimental results.

 

Key words: Ab-initio, ethyl bromide, gas-phase, kinetics, mechanism.