Non-equilibrium thermal dissociation of diatomic molecules. I. Extraction of collision-induced rate constants from experimentally measured reaction rates as a function of temperature for ten diatomic molecules dilute in Ar

Classical trajectory calculations for various atom-diatomic molecules were preformed using the three-dimensional Monte Carlo method. The reaction probabilities, cross-sections and rate constants of several systems were calculated. Equations of motion, which predict the positions and momenta of the colliding particles after each step, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecules. The results were compared with experimental ones and with other theoretical values. Good agreement was obtained between calculated rate constants and those obtained experimentally. Also, reasonable agreement was observed with theoretical rate constants obtained by other investigators using different calculation methods. The effects of the temperature, the nature of the colliding particles and the thermochemistry were studied. The results showed a strong dependence of the reaction rates on these factors.

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Kinetics of esterification of monoisopropylphenols with phosphoryl trichloride

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19891311 ◽

1989 ◽

Vol 54 (5) ◽

pp. 1311-1317

Author(s):

Miroslav Magura ◽

Ján Vojtko ◽

Ján Ilavský

Keyword(s):

Liquid Phase ◽

Rate Constants ◽

Reaction Rates ◽

Activation Energies ◽

The Individual ◽

Kinetics Of

The kinetics of liquid-phase isothermal esterification of POCl3 with 2-isopropylphenol and 4-isopropylphenol have been studied within the temperature intervals of 110 to 130 and 90 to 110 °C, respectively. The rate constants and activation energies of the individual steps of this three-step reaction have been calculated from the values measured. The reaction rates of the two isomers markedly differ: at 110 °C 4-isopropylphenol reacts faster by the factors of about 7 and 20 for k1 and k3, respectively. This finding can be utilized in preparation of mixed triaryl phosphates, since the alkylation mixture after reaction of phenol with propene contains an excess of 2-isopropylphenol over 4-isopropylphenol.

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Chemical-Reaction Rates in Non-equilibrium Viscous Compressible Flows

10.1063/1.3076584 ◽

2008 ◽

Author(s):

E.V. Kustova ◽

E. A. Nagnibeda ◽

D. Giordano ◽

Takashi Abe

Keyword(s):

Chemical Reaction ◽

Compressible Flows ◽

Reaction Rates ◽

Viscous Compressible Flows ◽

Chemical Reaction Rates ◽

Non Equilibrium

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Reactivity of cyclohex-1-enylcarboxylic and 2-methylcyclohex-1-enylcarboxylic acids with diazodiphenylmethane in aprotic solvents

Journal of the Serbian Chemical Society ◽

10.2298/jsc0012839n ◽

2000 ◽

Vol 65 (12) ◽

pp. 839-846

Author(s):

Jasmina Nikolic ◽

Gordana Uscumlic ◽

Vera Krstic

Keyword(s):

Hydrogen Bond ◽

Rate Constants ◽

Kinetic Data ◽

Linear Regression Analysis ◽

Spectroscopic Method ◽

Reaction Rates ◽

Aprotic Solvents ◽

Experimental Conditions ◽

Hydrogen Bond Acceptor ◽

Protic Solvents

Rate constants for the reaction of diazodiphenylmethane with cyclohex-1-enylcarboxylic acid and 2-methylcyclohex-1-enylcarboxylic acid were determined in nine aprotic solvents, as well as in seven protic solvents, at 30?C using the appropriate UV-spectroscopic method. In protic solvents the unsubsituted acid displayed higher reaction rates than the methyl-substituted one. The results in aprotic solvents showed quite the opposite, and the reaction rates were considerably lower. In order to explain the obtained results through solvent effects, reaction rate constants (k) of the examined acids were correlated using the total solvatochromic equation of the form: log k=logk0+s?*+a?+b?, where ?* is the measure of the solvent polarity, a represents the scale of the solvent hydrogen bond donor acidities (HBD) and b represents the scale of the solvent hydrogen bond acceptor basicities (HBA). The correlation of the kinetic data were carried out by means of multiple linear regression analysis and the opposite effects of aprotic solvents, as well as the difference in the influence of protic and aprotic solvents on the reaction of the two examined acids with DDM were discussed. The results presented in this paper for cyclohex-1-enylcarboxylic and 2-methylcyclohex-1-enylcarboxylic acids were compared with the kinetic data for benzoic acid obtained in the same chemical reaction, under the same experimental conditions.

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Kinetics of the thermal dissociation of diatomic molecules. II. Single-component system and mixtures of polyatomic gases

Combustion Explosion and Shock Waves ◽

10.1007/bf01465263 ◽

1974 ◽

Vol 10 (4) ◽

pp. 399-409 ◽

Cited By ~ 2

Author(s):

A. I. Osipov ◽

E. V. Stupochenko

Keyword(s):

Diatomic Molecules ◽

Thermal Dissociation ◽

Single Component ◽

Component System ◽

Polyatomic Gases ◽

Single Component System ◽

Kinetics Of

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Transport-controlled reaction rates under local non-equilibrium conditions

Geophysical Research Letters ◽

10.1029/2007gl029410 ◽

2007 ◽

Vol 34 (10) ◽

Cited By ~ 29

Author(s):

Xavier Sanchez-Vila ◽

Marco Dentz ◽

Leonardo David Donado

Keyword(s):

Reaction Rates ◽

Equilibrium Conditions ◽

Non Equilibrium

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Solvolyse und Phosphorylierungrseaktionen von Polyphosphorsäureestern / Solvolysis and Phosphorylating Activity of Polyphosphate Esters

Zeitschrift für Naturforschung B ◽

10.1515/znb-1971-0711 ◽

1971 ◽

Vol 26 (7) ◽

pp. 694-700 ◽

Cited By ~ 1

Author(s):

Hans Berger

Keyword(s):

Potentiometric Titration ◽

Rate Constants ◽

Reaction Rates ◽

High Rate ◽

Catalytic Effects ◽

Hydrolysis Of

Reaction rates of the ethanolysis and hydrolysis of the phenyl- and methylpolyphosphate-esters and of tetraphenylpyrophosphate were measured by potentiometric titration methods. Exceptionally high rate constants were obtained for the solvolysis of these compounds, some reactions occurring with half-times of less than 10 seconds. The phosphorylating activity of the phenylpolyphosphateester on polyfunctional nucleophilic compounds (SN2P-reaction) was tested and shown to exceed the activity of the conventional agent diphenylphosphoro-chloridate considerably. The catalytic effects of dimethylformamide were measured under several conditions and were shown to be complex solvent phenomena rather than conventional catalysis. The reactivity of the polyphosphate-esters is discussed with respect to their structure as well as the reactivity of P -O -P-bonds as a function of their ligands.

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