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  • 1980-1984  (126)
  • 1955-1959
  • 1982  (126)
  • Physical Chemistry  (126)
  • 101
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 585-591 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of O(3P) atoms with isobutane has been studied by using the discharge-flow system described previously [1]. The rate constant was measured from determinations of the isobutane concentration in the presence of an excess of O atoms and is given by k1 = (7.9 ± 1.4) × 107 dm3/mol·s at 307 K. In order to explain the observed reaction products, the mechanism requires that the principal process be the successive abstraction of H atoms from isobutane and from the t-butyl radical to give isobutene. A minor part of the reaction between O(3P) and the t-butyl radical gives the t-butoxy radical, which decomposes to acetone. The branching ratios are .
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  • 102
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 593-598 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Absolute rate constants for the reaction of OH with H2S have been measured over the temperature range of 239-425 K using the flash photolysis-resonance fluorescence technique. The results showed that the rate constants deviate slightly from Arrhenius behavior but can still be represented adequately by the following Arrhenius equation: \documentclass{article}\pagestyle{empty}\begin{document}$$k_{II} {\rm =}(7.8{\rm} \pm {\rm 2}{\rm .6}){\rm} \times {\rm 10}^{{\rm - 12}} {\rm exp[- (146} \pm {\rm 105)/}T]{\rm cm}^{\rm 3} /{\rm molec} \cdot {\rm s}s$$\end{document} Comparisons with recent literature values are presented.
    Additional Material: 2 Ill.
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  • 103
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of formation of the 1:1 complexes of some dialkyl-2,2′-bipyridyl-5,5′-dicarboxylates with the ion of Ni(II) have been determined by the stopped-flow spectrophotometric method. Second-order formation rate constants have been correlated with the Taft modification of the Hammett equation. A linear regression has been found (P = 0.95 confidence) with the following characteristics: slope = -0.6 ± 0.1; intercept = 1.32 ± 0.02 (log k0). An inductive effect of the alkyl groups upon the reaction of the complexation is proposed.
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  • 104
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 605-612 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pyrolysis of n-propyl allyl sulfide has been studied in static and stirred-flow systems at temperatures between 270 and 400°C. Propene and 2,4,6-triethyl-1,3,5-trithiane were the only reaction products. The order of the reaction was 0.99 ± 0.05 at 377°C. The first-order rate coefficients followed the Arrhenius equation \documentclass{article}\pagestyle{empty}\begin{document}$$k{\rm (s}^{- 1} {\rm) = 10}^{{\rm 11}{\rm .52} \pm {\rm 0}{\rm .16}} {\rm exp[(- 157} \pm {\rm 2) kJ/mol/R}T]$$\end{document} The rate coefficients and the product distribution remained unchanged when cyclohexene was used as carrier gas. A molecular mechanism involving a six-centered cyclic transition state is proposed to explain the present results. This mechanism is further supported by the pyrolysis of 4-thia-5-dideutero-1-heptene at 377°C, where only 3-deuteropropene is formed. The kinetic deuterium isotope effect had a value of 2.6 ± 0.3 at this temperature. The results are compared with those obtained in the pyrolysis of n-butyl allyl sulfide previously reported.
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  • 105
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 679-697 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A nozzle-beam-skimmer sampling system is used to measure species concentration profiles for a lean one-dimensional premixed CO—O2—Ar flame, into which small amounts of sulfur dioxide are introduced. The net formation rate for sulfur trioxide is obtained from the flux fraction profile for this species. The kinetic scheme is then utilized, along with the measured temperature profiles, to evaluate the rate coefficients k1 and k2 over the temperature range of 1435-1850 K. The most satisfactory agreement between the measured net formation rate for SO3 and that calculated on the basis of reactions (1) and (2) is obtained with the rate coefficients \documentclass{article}\pagestyle{empty}\begin{document}$$k_1 = 4.4 \times 10^{14} \exp [3163/T]{\rm cm}^{\rm 6} {\rm /mol}^{\rm 2} \cdot {\rm s}$$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$k_2 = 1.32 \times 10^{12} \exp [- 3070/T]{\rm cm}^{\rm 3} {\rm /mol} \cdot {\rm s}$$\end{document} Reactions (1) and (2) are found to be nearly balanced in a substantial region of the flame. Here the data are more sensitive to the difference in activation energies, as opposed to a particular value for either. Implications of this observation on the uncertainty of the deduced temperature dependence for each reaction are discussed, as are some of the procedures used in the data analysis.
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  • 106
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 733-733 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 107
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 861-874 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of CH3 radicals with O(3P) and O2 have been studied at 295 K in a gas flow reactor sampled by a mass spectrometer. For the reaction between CH3 and O, conditions were such that [O] » [CH3] and the methyl radicals decayed under pseudo-first-order conditions giving a rate coefficient of (1.14 ± 0.29) × 10-10 cm3/s. The reaction between CH3 and O2 was studied in separate experiments in which CH3 decayed under pseudo-first-order conditions. In this case, the rate coefficient obtained increased with increasing concentration of the helium carrier gas. This was varied over the range of 2.5-25 × 1016 cm-3, resulting in values for the apparent two-body rate coefficient ranging from 1 × 10-14 to 5.2 × 10-14 cm3/s. No evidence was found for the production of HCHO by a direct two-body process involving CH3 + O2, and an upper limit of 3 × 10-16 cm3/s was placed on the rate coefficient for this reaction. The experimental results for the apparent two-body rate coefficient exhibit the curvature one would expect for an association reaction in the fall-off region. Calculations used to extrapolate these measurements to the low-pressure limit yield a value for k0 of (3.4 ± 1.1) × 10-31 cm6/s, which is more than a factor of 2 higher than previous estimates.
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  • 108
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    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1033-1045 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photolysis of carbon tetrachloride in the presence of a number of alkanes has been investigated in the gas phase. The products obtained from the photolysis experiments were those expected from a chain reaction in which trichloromethyl radicals abstract hydrogen atoms from the alkane. The data have been used to determine Arrhenius parameters for hydrogen abstraction from the series of alkanes CH4, C2H6, C3H8, and i-C4H10 by trichloromethyl radicals, The rate data obtained are used to explain why termination reactions involving alkyl radicals become less significant as the alkane becomes more complex.
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  • 109
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1047-1051 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A chemical system, based on the Briggs-Rauscher reaction, which unperturbed undergoes rhythmic activity followed by a long period of iodine production-consumption prior to return of the rhythmic activity, is described. The effect of the various variables on the system is reported.
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  • 110
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1053-1055 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 111
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982) 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 112
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1059-1070 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hydrogen, cycloalkene, and bicycloalkyl were found to be the principal products which account for ≍97% of all products formed in the gas-phase radiolysis of water vapor containing low concentrations of cycloalkanes. From the ratios of cycloalkene-to-bicycloalkyl yields extrapolated to the zero dose, the self- and cross-disproportionation-to-recombination rate constant ratios Δ = kd/kc were determined for the following 12 reactions: Δ(c-C5H9, c-C5H9) = 0.73; Δ(c-C5D9, c-C5D9) = 0.58; Δ(c-C6H11, cC6H11) = 0.59; Δ(c-C6D11, c-C6D11) = 0.46; Δ(c-C5H9, c-C6H11) = 0.28; Δ(c-C5D9, c-C6H11) = 0.28; Δ(c-C5H9, c-C6D11) = 0.24; Δ(c-C5D9, c-C6D11) = 0.24; Δ(c-C6H11, c-C5H9) = 0.33; Δ(c-C6H11, c-C5D9) = 0.25; Δ(c-C6D11, c-C5H9) = 0.35; and Δ(c-C6D11, c-C5D9) = 0.28, where in the case of the cross-disproportionation the symbol Δ(R1,R2) is used to represent kd/kc for the disproportionation in which radical R1 captures a hydrogen (deuterium) atom from radial R2. The geometrical mean rule holds in the cross-combination reactions of cyclopentyl and cyclohexyl radicals. The kinetic isotope effect in the disproportionation reaction was determined as 1.24 ± 0.06.
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  • 113
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1139-1147 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of diphenyl sulfide with the two oxidants peroxydisulfate and peroxydiphosphate are described. With each oxidant, the reaction is first order in the oxidant and zero order in the substrate. The rate of the reaction is also independent of the effect of the substituent. Hydrogen ion catalyzes the reactions. The lack of inhibition of the reaction rate by added acrylamide rules out the possibility of a radical reaction initiated by the homolysis of the peroxyanions. From the effect of [H+] on the oxidation rates, the active species involved in the reactions have been determined. The redox reaction is essentially proceeding via hydrolysis of the protonated peroxy anions in a rate-determining step, followed by a fast step involving the oxidation of diphenyl sulfide to diphenyl sulfoxide. This has been confirmed by estimating the hydrolyzed products in each case and also by the product analyses.
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  • 114
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    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1149-1161 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The flash photolysis resonance fluorescence technique has been used to measure the rate constant for the reaction over the temperature range of 250-370 K. The present results are in excellent agreement with three very recent studies, and the combined data set can been used to derive the expression similar to that currently used in atmospheric modeling applications.A summary of our computer simulation of this reaction system is presented. The results of the computations indicate the absence of secondary reaction complications in the present work while revealing significant problems in the earlier (pre-1980) studies of the title reaction.
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  • 115
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: For the experimental determination of the equilibrium constant of the reaction CH3 + O2 ⇄ CH3O2 (1), the process of methane oxidation has been studied over the temperature range of 706-786 K. The concentration of CH3O2 has been measured by the radical freezing method, and that of CH3 from the rate of accumulation of ethane, assuming that C2H6 is produced by the reaction CH3 + CH3 → C2H6 (2). The equilibrium constant of reaction (1) has been obtained at four temperatures. For the heat of the reaction the value Δ˚H298 = -32.2 ± 1.5 kcal/mol is recommended.
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  • 116
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1243-1251 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate constants for the reactions have been measured directly by flash photolysis and kinetic spectroscopy. At room temperature, k3 = (3.4 ± 0.1) × 109 L/mol·s, independent of pressure in the range of 55-400 torr, and k6 = (2.1 ± 0.2) × 109 L/mol·s.
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  • 117
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    International Journal of Chemical Kinetics 14 (1982), S. 1267-1279 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of chlorination of toluene, o-methyl toluene, p-methyl toluene, m-methyl toluene, and m-chlorotoluene by chloramine-T(CAT) in aqueous acetic acid in the presence of HClO4 have been studied. The reaction is first order with respect to [CAT] as well as [H+]. The order with respect to the substrate is unity in the case of toluene and m-chlorotoluene, fractional in the case of o-methyl toluene and p-methyl toluene, and zero order in the case of m-methyl toluene. Nuclear halogenation has been observed with m-methyl toluene, while nuclear and side-chain halogenation for p-methyl toluene and o-methyl toluene, and sidechain halogenation for toluene and m-chlorotoluene are the pathways. An increase in the proportion of acetic acid accelerates the rate. Added acetate ions inhibit the reaction, and added p-toluene sulfonamide causes a pronounced retardation. A mechanism involving AcO+HCl as the important electrophile is discussed.
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  • 118
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1285-1286 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 119
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1281-1283 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 120
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of electron transfer from phenylhydrazine(S) to tris-(dimethylglyoximato) nickelate(IV), Ni(dmg)32- (dmg2- = dimethylglyoximate dianion), have been studied in aqueous medium in the range of 6.21 ≤ pH ≤ 12.2. The kinetics exhibit a pseudo-first-order disappearance of Ni(dmg)32- when excess S is present. The pseudo-first-order rate constants kobs are almost linearly dependent on [S]0 for varying concentrations of the reductant. At constant [S]0, the kobs-pH profile is U shaped. The kobs values register a decrease as the [H+] is increased in the pH range of ∽12.2-9.5, remain almost constant (minimum) in the range of ∽9-8, and then again linearly increase as [H+] is increased in the pH range of ∽7-6.21. Results are interpreted in terms of a probable mechanism involving outer-sphere electron transfer from the phenylhydrazine and phenylhydrazinium cation species to the unprotonated and one-protonated species of the Ni(IV) complex. The reduction rate appears to be dependent on the nature of the species (unprotonated and one-protonated) of the oxidant Ni(IV) complex. The phenylhydrazinium cation reduces the Ni(IV) complex at least one order of magnitude faster than does the neutral reductant species. The major product of the oxidation of phenylhydrazine by the Ni(IV) complex is 4-hydroxyazobenzene with a small amount of phenol.
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  • 121
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982) 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 122
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1287-1304 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An analysis of the thermochemistry of the kinetic parameters of the elementary reactions involved in the pyrolysis of pentachloroethane has resolved several disputed, unclarified, or inconsistent aspects of the reaction mechanism. The resulting mechanisms for the inhibited and uninhibited pyrolysis account for all reported experimental findings. On the basis of this interpretation, first experimentally based values have been derived for the following: DH0(CCl3-CHCl2) = 79.0 ± 1.0 kcal/mol, ΔHf0(CHCl2) = 25.7 ± 1.0 kcal/mol, and E1 = 59.7 ± 1.0 kcal/mol C2HCl5 .
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  • 123
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1315-1324 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of oxidation of triphenyl derivatives of group V elements Ph3M (M = P, As, Sb) by potassium peroxodisulfate have been investigated spectrophotometrically in 60% acetonitrile-40% water (v/v) mixture. The reaction follows second-order kinetics, first order in each reactant. Changes in the [H+] and ionic strength have negligible effect on the reaction rate. Addition of acrylonitrile fails to inhibit the rate. The results indicate a rate-determining nucleophilic displacement of the Ph3M molecule on the peroxide linkage. The relative rate order has been found to be Ph3P 〉 Ph3Sb 〉 Ph3As. This can be attributed to two conflicting trends.
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  • 124
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    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 14 (1982), S. 1305-1313 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Recent experimental data concerning the rate constants and their free energy of the outer sphere electron-transfer reactions, as catalyzed by noncoordinated pyridine derivatives in aqueous solution, are examined for possible correlation. For the electron transfer reactions between Vaq2+ or Euaq2+ and the bipyridyl derivatives, such as N,N'-dimethyl-4,4′-bipyridyl (paraquat) or diquat, the data are correlated quite well by the Marcus equation. The electron exchange rate constant, 5 × 107M-1·s-1, for an organic radical ion and its parent molecule obtained from semiquinones or their related compounds can be applied to these pyridine derivatives. However, in some cases such as electron transfer from paraquat or diquat cation radical to Co(en)33+, positive departures from the Marcus model are observed. These positive departures are interpreted in terms of interaction between the molecular orbitals of electron donors and electron acceptors in the transition state.
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  • 125
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    International Journal of Chemical Kinetics 14 (1982), S. 1325-1337 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase decomposition of n-heptyl-1 and n-heptyl-2 hydroperoxides C7H15OOH, which split into two radicals C7H15O and OH, has been investigated in the temperature range of 250-360°C. The decomposition has been carried out in a hydrogen-oxygen mixture (the hydroperoxide represents about 50 ppm) so as to avoid secondary reactions between the formed radicals and the reactants. Although the H2-O2 mixture is not spontaneously reactive in our conditions, it operates the transformation, through a fast and well-known process, of the OH radicals into HO2 radicals and then into H2O2. However, C7H15O radicals are also transformed into HO2 radicals and then into H2O2, but through an unknown process. To avoid heterogeneous reactions, vessel and probe are coated by B2O3 and then treated by the slow combustion of hydrogen at 510°C and 250 torr before the experiments are performed. As the reaction scheme is very simple, due to the use of the H2-O2 mixture, the determination of the evolutions of the HO2 concentration (followed by electronic paramagnetic resonance) lead to the determination of the gas-phase decomposition rate constant of hydroperoxides. For the n-heptyl-1 hydroperoxide the rate constant is \documentclass{article}\pagestyle{empty}\begin{document}$$(1.1 \pm 0.25) \times 10^{16} \exp - \left({\frac{{43,500 \pm 1000}}{{RT}}} \right){\rm s}^{{\rm - 1}}$$\end{document} and for the n-heptyl-2 hydroperoxide it is \documentclass{article}\pagestyle{empty}\begin{document}$$(7 \pm 2) \times 10^{15} \exp - \left({\frac{{41,500 \pm 1000}}{{RT}}} \right){\rm s}^{{\rm - 1}}$$\end{document}.
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  • 126
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    International Journal of Chemical Kinetics 14 (1982), S. 1339-1362 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method is described for extrapolating existing experimental data on the reactions of OH radicals with alkanes to higher temperatures using conventional transition-state theory. Expressions are developed for the estimation of the structural properties of the activated complex necessary for calculating ΔS± and ΔH±. The vibrational frequencies and internal rotations of the activated complex are given by those of the reacting alkane or the analogous alcohol and a set of additional internal modes that is the same for all OH + alkane reactions considered. Differences between primary, secondary, and tertiary hydrogen attack are discussed, and the validity of representing the activated complexes of all OH + alkane reactions by a fixed set of vibrational frequencies and other internal modes is evaluated. Calculations are presented for the reaction of OH with CH4, C2H6, C3H8, n-C4H10, i-C4H10, c-C4H8, c-C5H10, c-C6H12, (CH3)2CHCH(CH3)2, (CH3)3CCH(CH3)2, (CH3)4C, and (CH3)3CC(CH3)3, and the results are compared with experiments.
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