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Showing papers in "Journal of Physical and Chemical Reference Data in 1982"


Journal ArticleDOI
TL;DR: In this paper, a fundamental equation of state has been formulated for heavy water in the form Ψ = Ψ(p,T) in which Ω = Helmholtz free energyp = density T = thermodynamic temperature.
Abstract: A fundamental equation of state has been formulated for heavy water in the form Ψ = Ψ(p,T) in which Ψ = Helmholtz free energyp = density T = thermodynamic temperature. The complete range of single phase states in the range up to 100 MPa and 600 °C is covered by a single equation which is fitted both to P v T values, for saturated and unsaturated states, and to enthalpy values for saturation states only. The equation is constrained to fit the critical point conditions determined by Blank. It represents all thermodynamic properties of D2O, in the above range of states, within what is believed to be the accuracy of the experimental data.

1,776 citations



Journal ArticleDOI
TL;DR: In this paper, a critical evaluation of the kinetics and photochemistry of gas phase chemical reactions of neutral species involved in middle atmosphere chemistry (10-55 km altitude) was carried out under the auspices of the CODATA Task Group on Chemical Kinetics.
Abstract: This paper updates and extends a previous critical evaluation of the kinetics and photochemistry of gas phase chemical reactions of neutral species involved in middle atmosphere chemistry (10–55 km altitude) [J. Phys. Chem. Ref. Data 9, 295 (1980)]. The work has been carried out by the authors under the auspices of the CODATA Task Group on Chemical Kinetics. Data sheets have been prepared for 228 thermal and photochemical reactions, containing summaries of the available experimental data with notes giving details of the experimental procedures. For each reaction a preferred value of the rate coefficient at 298 K is given together with a temperature dependence where possible. The selection of the preferred value is discussed, and estimates of the accuracies of the rate coefficients and temperature coefficients have been made for each reaction. The data sheets are intended to provide the basic physical chemical data needed as input for calculations which model atmospheric chemistry. A table summarizing the preferred rate data is provided, together with an appendix listing the available data on enthalpies of formation of the reactant and product species.

428 citations


Journal ArticleDOI
TL;DR: The JANAF Thermochemical Tables as mentioned in this paper cover the thermodynamic properties over a wide temperature range with single phase tables for the crystal, liquid, and ideal gas state, in addition some multiphase tables are given.
Abstract: The thermodynamic tabulations previously published in four collections are extended by 227 new and revised tables. The JANAF Thermochemical Tables cover the thermodynamic properties over a wide temperature range with single phase tables for the crystal, liquid, and ideal gas state. In addition some multiphase tables are given. The properties given are heat capacity, entropy, Gibbs energy function, enthalpy, enthalpy of formation, Gibbs energy of formation, and the logarithm of the equilibrium constant for formation of each compound from the elements in their standard reference states. Each tabulation lists all pertinent input data and contains a critical evaluation of the literature upon which these values are based. Literature references are given.

350 citations


Journal ArticleDOI
TL;DR: In this article, a semi-empirical equation of the same type found to be effective in describing the thermal properties of NaCl solutions has been used to reproduce the volumetric data from O'°C to 300°C and 1 bar to 1000 bar.
Abstract: Literature data for the volumetric properties of sodium chloride solutions to concentrations of 5.5 molal have been compiled and critically evaluated. A semi‐empirical equation of the same type found to be effective in describing the thermal properties of NaCl solutions has been used to reproduce the volumetric data from O °C to 300 °C and 1 bar to 1000 bar. Tables of values are given for the specific volume, expansivity, and compressibility. Equations also are given for calculating the pressure dependence of the free energy, enthalpy, and heat capacity. These equations can be combined with a treatment of thermal properties to form a complete equation of state for sodium chloride solutions.

282 citations


Journal ArticleDOI
TL;DR: In this article, absolute rate constants for reactions of aliphatic carbon-centered radicals in aqueous solutions have been compiled and evaluated from the literature, including data for over 2,500 reactions of 373 radicals from 740 literature references.
Abstract: Absolute rate constants for reactions of aliphatic carbon‐centered radicals in aqueous solutions have been compiled and evaluated from the literature. Rate constants are included for reactions of radicals with inorganic and organic compounds and for decay by radical–radical reactions. The radicals were generated by radiolysis, photolysis, or other techniques, and their rate constants were determined generally by kinetic spectrophotometry. The tables include data for over 2,500 reactions of 373 radicals from 740 literature references.

226 citations


Journal ArticleDOI
TL;DR: In this article, the best available intensity data for some hundred or so molecules and evaluated their vibrational polarizabilities were collected, and the probable errors of the final numbers were given.
Abstract: An often overlooked, but nonetheless important, contribution to molecular dipole polarizabilities is that which comes from molecular vibration. This contribution, which was formerly called the atomic polarization, may be related to the intensities of the infrared‐active bands. In this paper we have collected the best available intensity data for some hundred or so molecules and evaluated their vibrational polarizabilities. We have also given estimates of the probable errors of the final numbers.

157 citations


Journal ArticleDOI
TL;DR: More than 700 studies have been reported to August 1980, with more than 15 diffusion measurement techniques as discussed by the authors, and a critical examination of these studies with a review of the techniques is presented.
Abstract: The property of diffusion is one of the basic properties of fluid systems. In molten salts, more than 700 studies have been reported to August, 1980, with more than 15 diffusion measurement techniques. A critical examination of these studies with a review of the techniques is presented. The results for more than 140 salt systems are reported in this communication as a series of data tables, with numerical values, value judgements, and literature citations. Silicates, slags, and oxide melts are excluded.

108 citations


Journal ArticleDOI
TL;DR: In this article, a table of coherent scattering cross sections, obtained by numerical integration of the Thomson formula, weighted by F2(x), for liquid water at eight temperatures between 4 °C and 200 C and for the free water molecule, for photon energies 5 keV to 1 MeV.
Abstract: Tabulations are presented of molecular form factors F(x), for values of x=sin(θ/2)/λ from 0 to 1.25 A−1, for liquid water at eight temperatures between 4 °C and 200 °C and for the free water molecule. For liquid water, x=0 to 1.25 A−1, the tabulated values are interpolated from experimental values of Narten and Levy (1971). For the free water molecule, x=0 to 1.25 A−1, the tabulated values are interpolated from calculated values of Blum (1971). For x=1.25 to 109 A−1, the independent atomic scattering hypothesis is assumed and the water molecular form factor F(x) is calculated from the hydrogen and oxygen atomic form factors given by Hubbell and Overbo (1979). Tables of coherent scattering cross sections, obtained by numerical integration of the Thomson formula, weighted by F2(x), are presented for liquid water at eight temperatures between 4 °C and 200 °C and for the free water molecule, for photon energies 5 keV to 1 MeV.

104 citations


Journal ArticleDOI
TL;DR: In this article, the heat capacity of poly(methyl methacrylate), polyacrylonitrile and polymethacrylamide is reviewed on the basis of measurements on 35 samples reported in the literature.
Abstract: Heat capacity of poly(methyl methacrylate), polyacrylonitrile, poly(methyl acrylate), poly(ethyl acrylate), poly(n‐butyl acrylate), poly(iso‐butyl acrylate), poly(octadecyl acrylate), poly(methacrylic acid), poly(ethyl methacrylate), poly(n‐butyl methacrylate), poly(iso‐butyl methacrylate), poly(hexyl methacrylate), poly(dodecyl methacrylate), poly(octadecyl methacrylate) and polymethacrylamide is reviewed on the basis of measurements on 35 samples reported in the literature. A set of recommended data are derived for each acrylic polymer in the amorphous state. Enthalpy and entropy functions are calculated for poly(methyl methacrylate) and polyacrylonitrile. This is the sixth paper in a series of publications which will ultimately cover all heat capacity measurements on linear macromolecules.

102 citations


Journal ArticleDOI
TL;DR: A comprehensive compilation of rate coefficients for vibration-to-vibration (V−V) and vibrationto-translation (V −T) energy transfer processes involving hydrogen halide molecules is presented in this article.
Abstract: A comprehensive compilation of rate coefficients for vibration‐to‐vibration (V−V) and vibration‐to‐translation (V−T) energy transfer processes involving hydrogen halide molecules is presented. The literature has been surveyed from 1966 to July 1981. Rate coefficients are grouped according to room temperature and low and high temperature results. Measured results are identified according to the type of process: V−V, V−T, or the sum of V−V and V−T processes. The method of measurement is identified along with the energy discrepancy, percent error, authors, and year of publication. The results are seen to be in excellent agreement when multiple measurements are available.

Journal ArticleDOI
TL;DR: In this paper, the microwave spectra of ethanol and propionitrile were reviewed and supplemented with spectral frequency calculations which include rotational and centrifugal distortion terms in the molecular Hamiltonian.
Abstract: The microwave spectra of ethanol (C2H5OH) and propionitrile (ethyl cyanide, C2H5CN) are critically reviewed and supplemented with spectral frequency calculations which include rotational and centrifugal distortion terms in the molecular Hamiltonian. The primary objective of this review is to provide the microwave transition frequencies applicable to molecular radio astronomy for the ground vibrational state of the most abundant isotopic forms, namely, 12C2H516OH and 12C2H512C14N. Since the internal rotation and hyperfine splittings for these species have not been resolved in most of the reported laboratory studies and also not detected in the molecular clouds observed by radio astronomers, these splittings have been ignored in the present calculations. All measured rotational transitions are included, however, the predicted transition frequencies were limited to J = 25 for ethanol and J = 30 for propionitrile over the range of 1 GHz to 300 GHz. A complete summary of the laboratory studies of both species ...

Journal ArticleDOI
TL;DR: In this paper, the rigid rotor-harmonic oscillator model has been used to estimate the ideal gas thermodynamic properties, C°p,S°,(G°−H°298)/T,H°t −H° 298/T,ΔH°F, ΔG°F and log Kp of formation for CH3, CD3 and CD4 in the temperature range O-3000 K and at 1 atmosphere.
Abstract: Ideal gas thermodynamic properties, C°p,S°,(G°−H°298)/T,H°t −H°298,ΔH°F,ΔG°F and log Kp of formation for CH3, CD3, CD4, C2D2, C2D4, C2D6, C2H6, CH3N2CH3 and CD3N2CD3 in the temperature range O–3000 K and at 1 atmosphere have calculated by statistical thermodynamic methods employing spectroscopic and other molecular constants. The rigid rotor‐harmonic oscillator model has been used. Estimated uncertainties in the thermodynamic properties due to uncertainties in the molecular properties and estimates of the effects of vibrational anharmonicities are also reported for each compound at three temperatures.

Journal ArticleDOI
TL;DR: In this article, peak absorption coefficients αmax for the J = 1←O, J = 2←1 and J = 3←2 rotational transitions in carbonyl sulphide have been calculated for the different isotopic molecular species in natural abundance and in each case for a range of vibrational states.
Abstract: Peak absorption coefficients αmax for the J = 1←O,J = 2←1 and J = 3←2 rotational transitions in carbonyl sulphide have been calculated for the different isotopic molecular species in natural abundance and in each case for a range of vibrational states. The results are tabulated for convenience both in order of values of αmax and in order of transition frequencies. Calculations have also been made, on a less extensive basis, for transitions from J = 4←3 to J = 25←24, and peak absorption coefficients have been tabulated, in order of values of αmax, for each of these transitions. The tables provide a frequency coverage of approximately 10 to 300 GHz. Comparison with available experimental results shows satisfactory agreement.

Journal ArticleDOI
TL;DR: In this paper, the evaluation results for the benzene+cyclohexane system are presented and the needs for new experimental data are defined, and the methods used to evaluate excess volume data are described.
Abstract: The methods used to evaluate excess volume data are described. The evaluation results for the benzene+cyclohexane system are presented. The needs for new experimental data are defined.

Journal ArticleDOI
TL;DR: In this article, the binary PTxy vapor-liquid equilibrium data for the benzene+hexane system were evaluated, and the needs for new experimental data were defined, as well as the criteria for new data.
Abstract: The binary PTxy vapor–liquid equilibrium data for the benzene+hexane system are evaluated. The needs for new experimental data are defined. Key words: activity coefficients; benzene; excess Gibbs function; hexane; vapor–liquid equilibrium.

Journal ArticleDOI
TL;DR: In this paper, the evaluation results for the benzene+cyclohexane system were presented, and the needs for new experimental data were defined, as well as the methods used to evaluate excess enthalpy data.
Abstract: The methods used to evaluate excess enthalpy data are described. The evaluation results for the benzene+cyclohexane system are presented. The needs for new experimental data are defined.

Journal ArticleDOI
TL;DR: The first in a series of reports on the critical evaluation of vapor-liquid equilibrium, heat of mixing, and volume change of mixing data for binary liquid mixtures of nonelectrolytes is presented in this paper.
Abstract: This paper is the first in a series of reports on the critical evaluation of vapor‐liquid equilibrium, heat of mixing, and volume change of mixing data for binary liquid mixtures of nonelectrolytes. The specific evaluation procedures for each property will be covered in subsequent articles. This paper describes the general procedures used to support the mixture evaluation work. The areas covered include the procedures used to cover the primary and secondary literature, the computer program libraries developed for pure compound and mixture data processing, the procedures used to evaluate and correlate the pure compound property data for use by the mixture programs, and the efforts made to make the best equation of state available to the vapor‐liquid equilibrium data reduction programs. Improvements are suggested for the presentation of mixture data in the literature.