70490-95-8Relevant academic research and scientific papers
Thermal Decomposition of CF2ClO2NO2
Xiong, Judy Qiuju,Carr, Robert W.
, p. 9811 - 9822 (1994)
The temperature and pressure dependence of the thermal decomposition kinetics of CF2ClO2NO2 in the presence of N2 diluent have been investigated over the temperature range 272-289 K and over the total pressure range 3-40 Torr by time-resolved mass spectrometry.The measurements were performed by directly monitoring the molecular ion CF2O2NO2+ (m/z=128), a fragment of Cf2ClO2NO2.The CF2ClO2NO2 decay rates are first order, with rate coefficients that are pressure dependent and well into the unimolecular falloff.The rate coefficients at 29 and 10 Torr can be expressed in Arrhenius form as kd(29 Torr) = (1.1+/-0.8)E16exp-1/RT>s-1; kd(10 Torr)=(2.6+/-1.6)E4exp-1/RT> s-1.The equilibrium constant has been determined to be K(T)=1.36E-28(T/298)-0.35exp-1/RT>cm-3 by combining decomposition rate coefficients with those for the reverse reaction (Int.J.Chem.Kinet. 1991, 23, 701-715).The value of the critical energy, 100 495 J mol-1, obtained from the equilibrium constant, has permitted a calculation of the limiting high-pressure unimolecular rate coefficient by means of a microcanonical method based on inversion of the interpolated partition function.It may be expressed in Arrhenius form as kdinfinite=6.7E16exp-1/RT> s-1.The pressure dependence of the unimolecular rate coefficients was fit by a variational RRKM calculation and by the FCENT method.The rate coefficients for the reverse reaction were also fit by these two procedures, yielding a unified model of the CF2ClO2NO2 CF2ClO2 + NO2 reaction over a range of temperature and pressure characteristic of the atmosphere.
Kinetics of the Reactions of CF2ClO2 Radicals with Nitrogen Dioxide
Moore, Steven B.,Carr, Robert W.
, p. 1393 - 1400 (1990)
The kinetics of the reaction of CF2ClO2 radicals with NO2 at 298 K, investigated by flash photolysis with time-resolved mass spectrometry, are reported.The peroxy radical, CF2ClO2, was formed in broadband flash photolysis of CF2ClBr in the presence of O2 and detected mass spectrometrically via the fragment ion, CF2O2+.With NO2 present, peroxy radical decay occurs by pseudo-first-order kinetics.The decay rates are also first order in NO2.The second-order rate coefficients are pressure dependent over the 1-10 Torr experimental range.The pressure-dependent rate coefficients were fitted by the Troe expression for termolecular reactions.Numerical simulation of the peroxy radical decay rates, using a mechanism consisting of known reactions that also occur in this system, were done to investigate the influence of secondary reactions on the measured rates.
Unimolecular Decomposition of Peroxynitrates
Zabel, F.
, p. 119 - 142 (2007/10/02)
Thermal decomposition rate constants of peroxynitric acid (HO2NO2) and chloromethyl peroxynitrate (CH2ClO2NO2) were measured as a function of temperature and total pressure in a photochemical reaction chamber of 420 l volume.Peroxynitrate concentrations were monitored by long-path IR absorption using a Fourier transform spectrometer.Analysis of these results in terms of unimolecular reaction rate theories yields kinetic parameters which allow to calculate decomposition rate constants of HO2NO2 and CH2ClO2NO2 for all pressures and temperatures which are of interest for atmospheric applications.These results, together with kinetic data on the thermal decomposition of other peroxynitrates previously obtained in our laboratory, allow to rationalize the change of the bond energies in peroxynitrates (RO2-NO2) with the nature of the group R.Combination of the decomposition data with experimental results on the reverse reactions from the literature are used to determine thermochemical data of peroxynitrates. - Keywords: Peroxynitric acid / Peroxynitrates / Thermal decomposition
