Journal of Physical and Chemical Reference Data

The surface tension tables presented herein are the result of a literature survey, evaluation, and compilation of data of some 2200 pure liquid compounds, 226 of which were reported for a single temperature. These are arranged with related compounds in the increasing order of their molecular weights. As far as possible the method of measurement, nature of atmosphere to which the liquid was exposed during measurements, and the estimated accuracy are given for each liquid. The tabulated values were calculated from the derived results of directly measured quantities reported in the literature of many countries from about 1874 to 1969. Preliminary plots of the experimentally measured quantities indicated that the surface tensions of the liquid compounds are linear functions of the temperature over the reported operational range. The principle of least squares was applied to experimental surface tension values to establish the regression curves and their equations. The constants of the equations (slope and intercept), together with the standard deviations are given for each compound. The selection factors establishing criteria of quality of surface tension data are discussed. These include (a) method of measurement, (b) purity of compound, (c) quality of apparatus and assembly, (d) experimental procedure (experimentation), (e) reliability of measurements (most probable values), (f) experience of investigator, and (g) availability of data. There are 274 references listed alphabetically.

The available data on gas-phase basicities and proton affinities of approximately 1700 molecular, radical and atomic neutral species are evaluated and compiled. Tables of the data are sorted (1) according to empirical formula and (2) according to evaluated gas basicity. This publication constitutes an update of a similar evaluation published in 1984.

An expanded and revised compilation on the reactivity of singlet oxygen, the lowest electronically excited singlet state of molecular oxygen, 1O2*(1Δg), in fluid solution is presented, which supersedes the publication of Wilkinson and Brummer, J. Phys. Chem. Ref. Data 10, 809 (1981). Rate constants for the chemical reaction and physical deactivation of singlet oxygen available through 1993 have been critically compiled. Solvent deactivation rates (kd) are tabulated for 145 solvents or solvent mixtures and second-order rate constants for interaction of singlet oxygen with 1915 compounds are reported.

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.

Literature data (through mid-1996) concerning the gas-phase reactions of alkanes and alkenes (including isoprene and monoterpenes) leading to their first generation products are reviewed and evaluated for tropospheric conditions. The recommendations of the most recent IUPAC evaluation [J. Phys. Chem. Ref. Data, 26, No. 3 (1997)] are used for the ⩽C3 organic compounds, unless more recent data necessitates reevaluation. The most recent review and evaluation of Atkinson [J. Phys. Chem. Ref. Data, Monograph 2, 1 (1994)] concerning the kinetics of the reactions of OH radicals, NO3 radicals, and O3 is also updated for these two classes of volatile organic compounds.

Dữ liệu động học cho các gốc tự do H⋅ và ⋅OH trong dung dịch nước, và các anion gốc tự do tương ứng, ⋅O− và eaq−, đã được phân tích kỹ qua phương pháp xung bức, xung quang học và các phương pháp khác. Hằng số tốc độ cho hơn 3500 phản ứng đã được lập bảng, bao gồm phản ứng với phân tử, ion và các gốc tự do khác có nguồn gốc từ các chất tan vô cơ và hữu cơ.

A survey of the available experimental data and the existing equations for the refractive index of water is given. The dependence of the molar refraction on wavelength, temperature, and density is shown over an extended range. Based upon the electromagnetic theory of light an equation for the refractive index of water with wavelength, temperature, and density as independent variables is constructed. Its coefficients are directly deduced from all available experimental data by least-squares fit. The range of validity of wavelength is restricted by the theory for normal dispersion to 182 nm≤λ≤2770 nm. The range of temperature and density is given by the available experimental data. Interpolations between the single measured points are possible and the following range of validity can be recommended: for temperature −10 °C≤T≤500 °C and for density 0.0028 kg/m3 ≤ρ≤1045 kg/m3. Good agreement exists between the new relation, the available experimental data, and several existing equations.

Mixture models explicit in Helmholtz energy have been developed to calculate the thermodynamic properties of refrigerant mixtures containing R-32, R-125, R-134a, R143a, and R-152a. The Helmholtz energy of the mixture is the sum of the ideal gas contribution, the compressibility (or real fluid) contribution, and the contribution from mixing. The independent variables are the density, temperature, and composition. The model may be used to calculate the thermodynamic properties of mixtures, including dew and bubble point properties, within the experimental uncertainties of the available measured properties. It incorporates the most accurate equations of state available for each pure fluid. The estimated uncertainties of calculated properties are 0.1% in density and 0.5% in heat capacities and in the speed of sound. Calculated bubble point pressures have typical uncertainties of 0.5%.

In the present paper an assessment of experimental and theoretical data on the structure and molecular vibrations of all the LnX3 lanthanide trihalides (X=F,Cl,Br,I) is presented. Our review includes 114 references to recent advanced studies. These data facilitated the confirmation of previously suggested trends in the molecular properties of the title compounds and a reliable estimation of the data of less-studied LnX3 molecules. On the basis of the collected data, a comparative analysis of the experimental and computational results has been performed. This served to assess the capabilities of recent theoretical methods for the above molecular properties.

The energy levels of the iron atom in all of its stages of ionization, as derived from the analyses of atomic spectra, have been compiled. In cases where only line classifications are given in the literature, level values have been derived. The percentages for the two leading components of the calculated eigenvectors of the levels are given where available. Ionization energies are also given.