Volume 8, Issue 3, July 1979
Index of content:
8(1979); http://dx.doi.org/10.1063/1.555604View Description Hide Description
The microwave spectrum of methyl formate is critically reviewed for information applicable to radio astronomy. The review is based on new laboratory measurements in the frequency range from 8 GHz to 58 GHz. Molecular data such as the derived rotational constants, centrifugal distortion parameters, internal rotation parameters, electric dipole moment and molecular structure are tabulated. Since the primary objective is to provide microwavespectral transitions applicable to radio astronomy observations, the review encompasses only the ground state rotational spectrum of the most abundant isotopic form of methyl formate, H12C16O2CH3. While all measured transitions are included, the predicted transitions were limited to J?12 in the range of 900 MHz to 250 GHz.
8(1979); http://dx.doi.org/10.1063/1.555605View Description Hide Description
Spectroscopic data related to the structures of polyatomic molecules in the gas phase have been reviewed, critically evaluated, and compiled. All reported bond distances and angles have been classified as equilibrium (r e ), average (r z ), substitution (r s ), or effective (r o ) parameters, and have been given a quality rating which is a measure of the parameter uncertainty. The surveyed literature includes work from all of the areas of gas‐phase spectroscopy from which precise quantitative structuralinformation can be derived. Introductory material includes definitions of the various types of parameters and a description of the evaluation procedure.
8(1979); http://dx.doi.org/10.1063/1.555606View Description Hide Description
An extensive evaluation is presented of the available gas phase chemical kineticrate constants for the interactions of the low lying electronic states of several atoms and molecules with numerous collision partners. These include the following excited states: C(21D2,21S0), N(22D3/2,5/2,22P1/2,3/2), P(32D3/2,5/2,32P1/2,3/2,), S(31D2,31S0). Se(43P0,41D2,41S0), Te(53P1,0,51D2,51S0), CO(a 3Π,a′3Σ+,d 3Δ,e 3Σ−,A 1Π), CS(a 3Π,A 1Π), OH(A 2Σ+), OD(A 2Σ+), O2(c 1Σ u −,C3Δ u ,A 3Σ u +,B3 Σ u −), and S2(a 1Δ g ,b 1Σ g +,A 3Σ u +, B3Σ u −). Wherever possible, recommended values are suggested. Much of the data refers only to room temperature. To facilitate the evaluation, collision‐free radiative lifetimes often have been required. These also have been evaluated and are presented. The mechanisms of the interactions and the various potential kinetic channels are discussed. These include such processes as chemical reactions, electronic quenching to the ground electronic state, electronic cross relaxation to an adjacent excited state, and for molecules, vibrational and rotational relaxation processes within the excited state. A complete coverage of the literature published prior to 1978 has been attempted.
A review, evaluation, and correlation of the phase equilibria, heat of mixing, and change in volume on mixing for liquid mixtures of methane+ethane8(1979); http://dx.doi.org/10.1063/1.555607View Description Hide Description
The available experimental data for liquid‐vapor equilibria, heat of mixing, and change in volume on mixing for the methane+ethane system have been reviewed and where possible evaluated for consistency. The derived properties chosen for analysis and correlation were liquid mixture excess Gibbs energies, Henry’s constants, and K values. Data sets, selected on the basis of the consistency tests applied, were correlated as functions of temperature and composition to provide internally consistent sets of property values suitable for engineering design calculations.
8(1979); http://dx.doi.org/10.1063/1.555608View Description Hide Description
Energy level data are given for the atom and all positive ions of aluminum (z=13). These data have been critically compiled, mainly from published material on measurements and analyses of the optical spectra. We have derived or recalculated the levels for a number of the ions. In addition to the level value in cm−1 and the parity, the J value and the configuration and term assignments are listed if known. Leading percentages from the calculated eigenvectors are tabulated wherever available. Ionization energies are given for all spectra.
8(1979); http://dx.doi.org/10.1063/1.555609View Description Hide Description
The energy levels of the calcium atom in all of its stages of ionization, as derived from the analyses of atomic spectra, have been critically compiled. In cases where only line classifications are reported in the literature, level values have been derived. Electron configurations, term designations, J‐values, experimental g‐values, and ionization energies are included. Calculated percentages of the two leading components of the eigenvectors of the levels are given.
8(1979); http://dx.doi.org/10.1063/1.555610View Description Hide Description
The advantages of using thermodynamic quantities divided by the gas constant (H/R, G/R, etc,) in calculations are described. It is recommended that thermodynamic tables be presented in this form, so that the entries are either dimensionless or in units of kelvins.