John T. Herron

Chemical Kinetic Data Base for Propellant Combustion I. Reactions Involving NO, NO2, HNO, HNO2, HCN and N2O

This publication contains evaluated chemical kinetic data on a number of single step elementary reactions involving small polyatomic molecules which are of importance in propellant combustion. The work involves the collection and evaluation of mechanistic and rate information and the use of various methods for the extrapolation and estimation of rate data where information does not exist. The conditions covered range from 500–2500 K and 1017–1022 particles/cm3. The results of the first years effort lead to coverage of all pertinent reactions of the following species; H, H2, H2O, O, OH, OCHO, CHO, CO, NO, NO2, HNO, HNO2, HCN, and N2O.

Evaluated Chemical Kinetics Data for Reactions of N(2D),N(2P), and N2(A 3Σu+) in the Gas Phase

Chemical kinetics data for the gas phase reactions of the first two electronically excited states of atomic nitrogen: N(2D) and N(2P), and of the first excited state of molecular nitrogen N2(A 3Σu+) are compiled and evaluated. The experimental data for 127 reactions are summarized, the experimental method and year of publication given, a recommended value given for the rate constant for each reaction at 298 K, and where possible, its temperature dependence. The reaction mechanisms are discussed within the limits of the available quantitative product yield data. The literature has been covered through early 1999. There are 94 references.

Thermochemical Data on Gas Phase Compounds of Sulfur, Fluorine, Oxygen, and Hydrogen Related to Pyrolysis and Oxidation of Sulfur Hexafluoride

Thermochemical data on selected gas phase compounds containing sulfur, fluorine, oxygen, and hydrogen are evaluated. These are of particular relevance to plasma chemistry and SF6 dielectric breakdown. Values of the enthalpies of formation and the entropy are provided at 298 K. Where no experimental data are available, methods for estimation have been developed for deriving the enthalpy of formation. Data are tabulated for 36 substances.

Rate Constants for the Reactions of Atomic Oxygen (O 3P) with Organic Compounds in the Gas Phase

Rate constants for the reactions of atomic oxygen (O 3P) with organic compounds in the gas phase are compiled and critically evaluated. Data are given here as originally reported in the literature for a total of 107 organic reactants. From a critical evaluation of the data, recommended values for rate constants are given over specified temperature intervals, and where possible at 298 K and 1000 K. Estimated error limits are assigned to all recommended values.

Evaluated Chemical Kinetic Data for the Reactions of Atomic Oxygen O(3P) with Saturated Organic Compounds in the Gas Phase

Rate constants and mechanisms for the gas phase reactions of atomic oxygen O(3P) with organic compounds having only saturated C–C bonds are compiled and critically evaluated. Data are given for the alkanes, cycloalkanes, haloalkanes, oxygen and nitrogen containing organic compounds, and free radicals. In addition, data are given for some miscellaneous compounds containing boron, silicon, germane, and mercury. From a critical examination of the data, recommended values for rate constants are given over specified temperature intervals or at specified temperatures. Error limits are assigned to all recommended values.

Chemical Kinetics Database and Predictive Schemes for Nonthermal Humid Air Plasma Chemistry. Part II. Neutral Species Reactions

Reliable kinetics data are necessary input for models describing the decomposition of gases in electric discharge or electron-beam devices. In this second part of a continuing series, we provide a core database describing the dominant reactions of neutral species in nonthermal low temperature (300–700K) pulsed plasmas containing humid air. Recommended rate constants and extrapolation methods are provided in a manner to facilitate prediction of reactivities as a function of temperature and pressure.

Mass‐Spectrometric Study of the Reactions of O Atoms with NO and NO2

The reactions of O atoms with NO and NO2 have been studied using a mass spectrometer to directly measure the O‐atom partial pressure. The results obtained are as follows: NO+O+M→NO2+M,  k1(M  is  N2)=(1.44±0.20)×1015exp (1930±100/RT) cc2 mole−2·sec−1;NO2+O→NO+O2,  k2=(1.95±0.61)×1013exp (−1060±200/RT) cc mole−1·sec−1.These reactions are discussed in terms of the general mechanism O+XO⇌ lim BA[OXO]*+M→ lim CXO2+M→ lim DX+O2→ lim EXO2+hv.The rates of the elementary reaction steps have been calculated from the over‐all rate constants and previous results on the isotopic exchange rates of 18O with O2, NO, and NO2.

Survey of Photochemical and Rate Data for Twenty‐eight Reactions of Interest in Atmospheric Chemistry

Photochemical and rate data have been evaluated for 28 gas phase reactions of interest for the chemistry of the stratosphere. The results are presented on data sheets, one per reaction. For each reaction, the available data are summarized. Where possible there is given a preferred value for the rate constant or, for the photochemical reactions, preferred values for primary quantum yields and optical absorption coefficients.

Absolute rate constants for the reaction O(3P)+NO2→NO+O2 over the temperature range 230–339°K

Using the technique of flash photolysis‐resonance fluorescence, absolute rate constants have been measured for the reaction O(3P)+NO2→ NO+O2. Over the temperature range 230–339°K, the rate constant was found to have the value k=9.12± 0.44 × 10−12cm3 molecule−1sec−1, independent of temperature. At stratospheric temperatures, this rate constant is about a factor of two faster than indicated from previous measurements.

Absolute Rate Constants for the Reaction of Atomic Oxygen with Ethylene over the Temperature Range 232–500°K

Rate constants for the reaction of atomic oxygen with ethylene were measured over a temperature range of 232–500°K using the flash photolysis‐resonance fluorescence technique. The rate constant at room temperature was also determined using a flash photolysis‐kinetic absorption spectroscopy system and a discharge‐flow system coupled to a mass spectrometer. Within the experimental errors of the three techniques, good agreement was found for the rate constant at 298°K. The bimolecular rate constant was also found invariant to changes in both total pressure and reactant concentration. Over the temperature range of the experiments, the rate data could be fitted by a simple Arrhenius expression of the form, k=5.42± 0.30× 10−12 exp[(−1130± 32 cal mole−1)/RT]cm3molecule−1· sec−1.