@article {1548, title = {Density functional theory calculation of 2p core-electron binding energies of Si, P, S, Cl, and Ar in gas-phase molecules}, journal = {Journal of Electron Spectroscopy and Related Phenomena}, volume = {151}, number = {1}, year = {2006}, note = {ISI Document Delivery No.: 017GXTimes Cited: 12Cited Reference Count: 40}, month = {Mar}, pages = {9-13}, type = {Article}, abstract = {Density functional theory (DFT) calculations have been performed on the gas-phase 2p core-electron binding energies (CEBEs) of Si and Ar in 145 cases using the following procedure: AEKS (scalar-ZORA + E-xc)/TZP//HF/6-31G(d). Delta E-KS is the difference in the total Kohn-Sham energies of the 2p-ionized cation and the neutral parent molecule calculated by DFT using different exchange-correlation functionals E-xc with triple-zeta polarized basis set, at molecular geometry optimized by HF/6-31G(d), and relativistic effects have been estimated by scalar zeroth-order regular approximation. Among the 26 functionals tested, the form of E-xc giving the best overall performance was found to be the combination of OPTX exchange and LYP correlation functionals. For that functional, the average absolute deviation (AAD) of the 145 calculated CEBEs from experiment is 0.26 cV. There are seven other exchange-correlation functionals that led to AADs of less than 0.30 eV. Some functionals give lower AADs than E-xc=OPTX-LYP for some individual elements. In the case of Si, for example, the combination of either mPW91-PBE or Becke88-Perdew86 led to an AAD of only 0.10 eV for 56 silicon-containing molecules. Another example is the case of the argon atom, for which the choice of E-xc=OPTX-Perdew86 yields a value for CEBE equal to the experimental value. (c) 2005 Elsevier B.V. All rights reserved.}, keywords = {ABSORPTION, ACCURATE, Ar(2p), ARGON, BEHAVIOR, Cl(2p), emission, ESCA, EXCHANGE-ENERGY, GENERALIZED GRADIENT APPROXIMATION, L-shell ionization, P(2p), POTENTIALS, RAY PHOTOELECTRON-SPECTROSCOPY, S(2p), Si(2p), SILICON, XPS}, isbn = {0368-2048}, url = {://000235683200003}, author = {Segala, M. and Takahata, Y. and Chong, D. P.} } @article {4796, title = {Noble gas-metal chemical bonding: the microwave spectra, structures and hyperfine constants of Ar-AuF and Ar-AuBr}, journal = {Physical Chemistry Chemical Physics}, volume = {2}, number = {18}, year = {2000}, note = {ISI Document Delivery No.: 353RKTimes Cited: 47Cited Reference Count: 33}, pages = {3943-3948}, type = {Article}, abstract = {The rotational spectra of the complexes Ar-AuF and Ar-AuBr have been observed in the frequency range 7-22 GHz using a pulsed-jet cavity Fourier transform microwave spectrometer. Both complexes are linear and rather rigid in the ground vibrational state, with the Ar-Au stretching frequency estimated as similar to 200 cm(-1). Isotopic data have been used to calculate an r(0) structure for Ar-AuBr while for Ar-AuF only an estimation of the r(0) geometry could be made. Ab initio calculations at the MP2 level of theory model the geometries and stretching frequencies well and predict an Ar-Au bond energy in Ar-AuF of similar to 60 kJ mol(-1). The Au nuclear quadrupole coupling constant changes significantly on complex formation, indicating extensive charge arrangement. This in conjunction with the large dissociation energy and ab initio results show that the Ar-Au bonds in these complexes are weakly covalent in nature.}, keywords = {ARGON, COMPLEXES, CORRELATED MOLECULAR CALCULATIONS, FOURIER-TRANSFORM SPECTROSCOPY, GAUSSIAN-BASIS SETS, NQR, RAMAN, ROTATIONAL SPECTRUM, STATES}, isbn = {1463-9076}, url = {://000089289100001}, author = {Evans, C. J. and Rubinoff, D. S. and Gerry, M. C. L.} } @article {4795, title = {Noble gas-metal chemical bonds. Microwave spectra, geometries, and nuclear quadrupole coupling constants of Ar-AuCl and Kr-AuCl}, journal = {Journal of the American Chemical Society}, volume = {122}, number = {25}, year = {2000}, note = {ISI Document Delivery No.: 332CBTimes Cited: 70Cited Reference Count: 41}, month = {Jun}, pages = {6100-6105}, type = {Article}, abstract = {The pure rotational spectra of Ar-AuCl and Kr-AuCl have been measured using a pulsed-jet cavity Fourier transform microwave spectrometer. Both complexes have been found to be linear and are relatively rigid in their ground vibrational states. The noble gas-gold stretching frequencies have been estimated to be 198 and 161 cm(-1) for Ar-AuCl and Kr-AuCl, respectively. From the isotopic data obtained. ro structures have been calculated for both Ar-AuCl and Kr-AuCl, while a partial substitution (r(s)) structure has been obtained for Kr-AuCl. The Ar-Au distance has been found to be 2.47 Angstrom, while the Kr-Au distance is 2.52 Angstrom. Ab initio calculations have been performed at the MP2 level of theory on both complexes to obtain geometries, vibrational frequencies, and dissociation energies. The dissociation energies for Ar-AuCl and Kr-AuCl have been estimated to be 47 and 71 kJ mol(-1), respectively. The nuclear quadrupole coupling constant of Au has been found to change significantly on complex formation (to -259.8 MHz in Ar-AuCl, and -349.9 MHz in Kr-AuCl) from its value in the monomer unit (+9.6 MHz in AuCl), which is consistent with extensive charge rearrangement on formation of the complexes. This, in conjunction with the sizable dissociation energies, indicates that the Ar-Au and Kr-Au bonds are weakly covalent.}, keywords = {ARGON, ATOMS, CORRELATED MOLECULAR CALCULATIONS, DER-WAALS COMPLEXES, FOURIER-TRANSFORM SPECTROSCOPY, GAUSSIAN-BASIS SETS, LASER-ABLATION, RAMAN, ROTATIONAL, SPECTRUM, STATES}, isbn = {0002-7863}, url = {://000088054900021}, author = {Evans, C. J. and Lesarri, A. and Gerry, M. C. L.} } @article {4885, title = {Prediction of the thermal conductivity of gases based on the Rainwater-Friend theory and a new corresponding states function}, journal = {Physica a-Statistical Mechanics and Its Applications}, volume = {275}, number = {1-2}, year = {2000}, note = {ISI Document Delivery No.: 270GXTimes Cited: 14Cited Reference Count: 52}, month = {Jan}, pages = {48-69}, type = {Article}, abstract = {The Rainwater-Friend theory is used for the evaluation of the initial density dependence of the thermal conductivity of the noble gases using accurate realistic potentials. This theory, which was originally developed for spherically symmetric potentials, is adapted for the calculation of the initial density dependence of the translational contribution of the thermal conductivity of polyatomic gases. The internal state contribution is evaluated using a combination of Mason-Monchick theory and hard-sphere Enskog theory. At high density, beyond the range of the Rainwater-Friend theory, a deviation thermal conductivity function has been presented. With the help of this function, an easily usable corresponding-states function for the calculation of the thermal conductivity of supercritical gases has been developed, which is valid over a wide temperature range and for pressures up to 400 MPa. (C) 2000 Elsevier Science B.V. All rights reserved.}, keywords = {ARGON, CARBON-DIOXIDE, high-pressure thermal conductivity, INITIAL DENSITY-DEPENDENCE, NOBLE-GASES, PHYSICAL-PROPERTIES, POLYATOMIC GASES, POTENTIAL-ENERGY CURVE, Rainwater-Friend theory, second, TEMPERATURE, thermal conductivity, thermal conductivity virial coefficient, TRANSPORT-PROPERTIES, ZERO DENSITY}, isbn = {0378-4371}, url = {://000084528200005}, author = {Najafi, B. and Araghi, R. and Rainwater, J. C. and Alavi, S. and Snider, R. F.} } @article {4316, title = {The coupling of electron thermalization and electron attachment in CCl4/Ar and CCl4/Ne mixtures}, journal = {Journal of Chemical Physics}, volume = {108}, number = {4}, year = {1998}, note = {ISI Document Delivery No.: YR488Times Cited: 11Cited Reference Count: 61}, month = {Jan}, pages = {1587-1600}, type = {Article}, abstract = {The relaxation of a nonequilibrium distribution of electrons in a mixture of CCl4 with either Ar or Ne is studied. In this paper, electron-CCl4 and electron-inert gas elastic collisions, vibrationally inelastic collisions between electrons and CCl4, as well as the electron attachment reaction with CCl4, are included in the analysis. The time dependent electron energy distribution function is determined from the Boltzmann equation and the energy relaxation times are determined. The coupling of the thermalization process and the attachment process are discussed in detail. The results from the calculations are analyzed analogous to experimental studies, and the methodology of the experimental reduction of the data is studied. (C) 1998 American Institute of Physics.}, keywords = {ARGON, CONDUCTIVITY, CROSS-SECTIONS, DEGRADATION, development, FIELD DEPENDENCE, MONTE-CARLO SIMULATION, RARE-GAS MODERATORS, SF6, SWARM, TRANSPORT}, isbn = {0021-9606}, url = {://000071500300035}, author = {Kowari, K. and Leung, K. and Shizgal, B. D.} } @article {4364, title = {Improved initial density dependence of the viscosity and a corresponding states function for high pressures}, journal = {Physica a-Statistical Mechanics and Its Applications}, volume = {260}, number = {1-2}, year = {1998}, note = {ISI Document Delivery No.: 135WLTimes Cited: 24Cited Reference Count: 50}, month = {Nov}, pages = {31-48}, type = {Article}, abstract = {The initial density correction to gaseous viscosity using accurate realistic potentials of the noble gases is evaluated using the Rainwater-Friend theory. It is shown that this theory works satisfactorily for densities up to about 2 mol dm(-3). Due to the superimposability of the noble gas potential functions, a universal function of the reduced second viscosity virial coefficient is obtained over the entire reduced temperature range. At densities beyond the range of the theory, a variant of the excess viscosity is developed, by which the viscosity of the different gases can be easily calculated above the critical temperature for pressures up to 900 MPa. The accuracy of this method is within the experimental uncertainties. (C) 1998 Elsevier Science B.V. All rights reserved.}, keywords = {11 POLYATOMIC GASES, ARGON, COEFFICIENT, COEFFICIENTS, EQUILIBRIUM, high-pressure excess viscosity, NOBLE-GASES, ORGANIC VAPORS, PHYSICAL-PROPERTIES, Rainwater-Friend theory, second viscosity virial, TEMPERATURE, THERMAL-CONDUCTIVITY, TRANSPORT-PROPERTIES, VISCOSITY}, isbn = {0378-4371}, url = {://000076825600004}, author = {Najafi, B. and Ghayeb, Y. and Rainwater, J. C. and Alavi, S. and Snider, R. F.} } @article {3725, title = {On the existence of a steady electron distribution for systems with electron attachment: Ar-CCl4 mixtures}, journal = {Chemical Physics Letters}, volume = {260}, number = {3-4}, year = {1996}, note = {ISI Document Delivery No.: VJ539Times Cited: 1Cited Reference Count: 18}, month = {Sep}, pages = {365-370}, type = {Article}, abstract = {The relaxation of a nonequilibrium distribution of electrons in a mixture of Ar and CCl4 is studied. In a previous paper [J. Phys. B 34 (1991) 2909], Shizgal demonstrated that with the neglect of vibrationally inelastic collisions, a nonequilibrium steady electron distribution does occur even with the loss of electrons. The rate of disappearance of electrons due to attachment is rapid for high concentrations of CCl4. In this Letter, we extend the previous analysis to include inelastic collisions and find that for CCl4 and Ar mixtures there is no steady electron distribution function with increasing molecular gas concentrations.}, keywords = {ARGON, CROSS-SECTIONS, DEGRADATION, GAS, SF6, THERMALIZATION}, isbn = {0009-2614}, url = {://A1996VJ53900008}, author = {Kowari, K. and Shizgal, B.} } @article {2834, title = {PURE ROTATIONAL SPECTRA OF THE MIXED RARE-GAS VAN-DER-WAALS COMPLEXES NE-XE, AR-XE, AND KR-XE}, journal = {Journal of Chemical Physics}, volume = {99}, number = {2}, year = {1993}, note = {ISI Document Delivery No.: LM894Times Cited: 48Cited Reference Count: 50}, month = {Jul}, pages = {919-927}, type = {Article}, abstract = {Pure rotational transitions in the vibrational ground states of various isotopomers of the heteronuclear rare gas dimers Ne-Xe, Ar-Xe, and Kr-Xe have been measured using a pulsed molecular beam cavity microwave Fourier transform spectrometer. Rotational and centrifugal distortion constants have been obtained, and have yielded estimates of the lengths of the van der Waals bonds and of their harmonic vibration frequencies. Effects due to nuclear quadrupole coupling have been observed in Xe-131-containing complexes and have yielded the corresponding nuclear quadrupole coupling constants. The electric molecular dipole moments of the complexes have been estimated from the excitation pulse lengths, optimized for maximum signal strength (pi/2 condition).}, keywords = {ARGON, CONSTANTS, curve, DIPOLE-MOMENTS, EXCITED-STATES, INTERATOMIC POTENTIALS, PAIRS, SPECTROMETER, TRANSFORM MICROWAVE SPECTROSCOPY, ULTRAVIOLET-LASER SPECTROSCOPY}, isbn = {0021-9606}, url = {://A1993LM89400017}, author = {Jager, W. and Xu, Y. J. and Gerry, M. C. L.} } @article {7175, title = {ATOMIC EXCITATION IN A JET-ASSISTED GLOW-DISCHARGE PLASMA PLUME}, journal = {Spectrochimica Acta Part B-Atomic Spectroscopy}, volume = {47}, number = {11}, year = {1992}, note = {ISI Document Delivery No.: JN613Times Cited: 9Cited Reference Count: 41}, month = {Oct}, pages = {1287-1307}, type = {Article}, abstract = {A jet-assisted glow discharge emission source has previously been shown to suffer from self-absorption when the viewing axis is orientated in line with the support gas flow. This problem can be alleviated by rotating the viewing axis 90-degrees so that the absorption path length is significantly reduced; however, in viewing side-on, line-of-sight measurements of the plasma plume can be accomplished no closer than 25 mm from the sample surface due to geometry limitations. At this axial distance from the sample, the plume shows no Ar 11 emission, which differentiates it from the negative glow. Furthermore. evidence was found that the plume possesses features similar to flowing afterglows: energy is transported from the negative glow to the plume through argon metastable atoms. The collision of two metastable argon atoms produces ionization to the ground state of the argon ion, deactivation to the ground state of the argon atom and an energetic electron (7.32-7.68 eV) which is capable of exciting sputtered atoms. A strong correlation is observed between the square of the argon metastable population and the emission intensity for Cu I and Zn I as the jet flow rate is manipulated.}, keywords = {ARGON, ICP, ION-SOURCE, LAMP, MASS-SPECTROMETRY, PERFORMANCE, STATE}, isbn = {0584-8547}, url = {://A1992JN61300005}, author = {Banks, P. R. and Blades, M. W.} } @article {7034, title = {CHARACTERIZATION OF AN ATMOSPHERIC-PRESSURE PARALLEL-PLATE CAPACITIVELY COUPLED RADIOFREQUENCY PLASMA}, journal = {Applied Spectroscopy}, volume = {45}, number = {9}, year = {1991}, note = {ISI Document Delivery No.: GR646Times Cited: 17Cited Reference Count: 37}, month = {Nov}, pages = {1468-1477}, type = {Article}, abstract = {A new design for a radio-frequency, atmospheric-pressure, parallel-plate capacitively coupled plasma (CCP) which uses water-cooled electrodes is described. Four different sizes of quartz tubes were compared with respect to spatial emission features for support gas and analyte species. Torches studied had the following inside dimensions: a 1-mm capillary tube with round cross section, a 2 x 4 mm tube, a 4 x 4 mm tube, and a 6 x 6 mm tube. Relative emission intensities of near-infrared lines for F, Cl, Br, I, C, N, and O atomic and ionic lines excited with the use of the He-CCP are tabulated. The detection limits range from 10 to 78 pg/s.}, keywords = {ARGON, ATOMIC EMISSION SPECTROSCOPY, capacitively coupled plasma, CHLORINE, DETECTOR, EXCITATION, GAS-CHROMATOGRAPHIC, HELIUM PLASMA, MICROWAVE-INDUCED PLASMA, NEAR-INFRARED EMISSION, NONMETAL ATOMIC EMISSION, RED, SPECTRA, SPECTROMETRY}, isbn = {0003-7028}, url = {://A1991GR64600012}, author = {Huang, D. G. and Blades, M. W.} } @article {7058, title = {TIME-DEPENDENT ELECTRON-DISTRIBUTION FUNCTIONS AND DEGRADATION SPECTRA - A COMPARISON OF THE SPENCER-FANO EQUATION AND THE BOLTZMANN-EQUATION}, journal = {Applied Radiation and Isotopes}, volume = {42}, number = {10}, year = {1991}, note = {ISI Document Delivery No.: GL858Times Cited: 8Cited Reference Count: 43SYMP ON THE PHYSICS OF ELECTRON TRANSPORTAPR 02-03, 1990GAITHERSBURG, MDUS DOE, OFF HLTH \& ENVIRONM RES}, pages = {985-994}, type = {Proceedings Paper}, abstract = {The thermalization of electrons in gaseous moderators for initial nonequilibrium distributions not far removed from thermal energies has been studied previously with a Fokker-Planck equation for electron distribution. For electron energies in the keV to eV energy range an approach based on the Spencer-Fano equation has also been used. The present paper considers a detailed comparison of the two approaches to electron thermalization. The Spencer-Fano equation is analogous to the Fokker-Planck equation but with the moderator temperature set to zero, that is, with the cold gas approximation. The effect of the cold gas approximation on the time evolution of the nonequilibrium distributions and on the calculation of thermalization times is discussed in detail. The cold gas approximation is shown to be the basis for most of the concepts used in radiation chemistry and physics to study electron degradation. Applications to the thermalization of electrons in the inert gases are considered. The analysis is restricted to elastic electron-moderator collisions.}, keywords = {ARGON, HELIUM, HOT-ATOM REACTIONS, INITIAL PRODUCTS, NITROGEN, RARE-GAS MODERATORS, SUBEXCITATION ELECTRONS, THERMALIZATION, TRANSPORT, YIELDS}, isbn = {0969-8043}, url = {://A1991GL85800010}, author = {Kowari, K. and Shizgal, B.} }