bluuebunny/crossref_metadata_2025 huggingface dataset:
Size-dependent properties of ballistic silicon nanowire field effect transistors
Authors: Lee Yeonghun , Kakushima Kuniyuki , Shiraishi Kenji , Natori Kenji , Iwai Hiroshi
Published: June 2010

A study on size-dependent subband structures of silicon nanowires (SiNWs) aligned along [100] direction, ranging from 0.77 to 2.69 nm in width, is performed by the first-principles calculation. Combined with a compact model adopting Landauer’s formula, on-currents of ballistic SiNW field effect transistors (FETs) are estimated and assessment of size-dependent performance is conducted. Size-dependent injection velocity strongly depends on Fermi level measured from the conduction band edge when carriers are degenerate. It is also supposed that the Fermi level has a peak value at a certain wire width. Despite variation in the size-dependent Fermi level and injection velocity, large SiNW FETs show large on-currents owing to their larger gate capacitances resulting from longer periphery. The on-current in the case of a multichannel SiNW FET reveals that size-dependent subband structures of nanowires have a serious effect on performance. As the results, although the normalized on-current decreases with decrease in wire width in the assessed multichannel FETs because both the saturation velocities and the normalized capacitances decrease, there can be a maximum in the normalized on-current in a larger wire owing to the maximized Fermi level and injection velocity.
Irreducible modules over finite simple Lie conformal superalgebras of type K
Authors: Boyallian Carina , Kac Victor G. , Liberati José I.
Published: June 2010

We construct all finite irreducible modules over Lie conformal superalgebras of type K.
Microscopic computational model of a superfluid
Authors: Ovchinnikov M. , Novikov Alexey
Published: June 2010

A finite one-dimensional microscopic model of a superfulid is presented. The model consists of interacting Bose particles with an additional impurity particle confined to a ring. Both semiclassical and exact quantum calculations reveal dissipationless motion of impurity with increased effective mass due to its interaction with the excitations of Bose fluid. It is shown that both the excitation spectrum of Bose fluid and the excitation spectrum of impurity can be analyzed using the structure of the ground state of the system.
Semiclassical propagation of Wigner functions
Authors: Dittrich T. , Gómez E. A. , Pachón L. A.
Published: June 2010

We present a comprehensive study of semiclassical phase-space propagation in the Wigner representation, emphasizing numerical applications, in particular as an initial-value representation. Two semiclassical approximation schemes are discussed. The propagator of the Wigner function based on van Vleck’s approximation replaces the Liouville propagator by a quantum spot with an oscillatory pattern reflecting the interference between pairs of classical trajectories. Employing phase-space path integration instead, caustics in the quantum spot are resolved in terms of Airy functions. We apply both to two benchmark models of nonlinear molecular potentials, the Morse oscillator and the quartic double well, to test them in standard tasks such as computing autocorrelation functions and propagating coherent states. The performance of semiclassical Wigner propagation is very good even in the presence of marked quantum effects, e.g., in coherent tunneling and in propagating Schrödinger cat states, and of classical chaos in four-dimensional phase space. We suggest options for an effective numerical implementation of our method and for integrating it in Monte-Carlo–Metropolis algorithms suitable for high-dimensional systems.
Magnetic properties and phase stability of L21 phase in Co2Mn(Ga1−xZx)(Z=Si, Ge, and Sn) Heusler alloys
Authors: Okubo A. , Umetsu R. Y. , Kobayashi K. , Kainuma R. , Ishida K.
Published: June 2010

For the Co2Mn(Ga1−xZx) (Z=Si, Ge, and Sn) Heusler alloys, the L21/B2 order-disorder transition temperature TtL21/B2, the Curie temperature TC, and the saturation magnetization Ms were determined. The TtL21/B2 for all the systems linearly increases with increasing x. Although the TtL21/B2 was not determined in the high x region because of melting of alloys, those of Co2MnGe and Co2MnSn could be estimated by extrapolation from the quaternary data. The Ms at 4.2 K and the TC increase with x, and the Ms for all the systems is in good agreement with the Slater Pauling rule.
An experimental analysis of elliptical adhesive contact
Authors: Sümer Bilsay , Onal Cagdas D. , Aksak Burak , Sitti Metin
Published: June 2010

The elliptical adhesive contact is studied experimentally utilizing two hemicylinders of elastomeric poly(dimethylsiloxane) (PDMS). Experimental results are compared with the recent approximate Johnson–Kendall–Roberts (JKR) theory for elliptical contacts, and the deviation of the experiments from this theory is discussed in detail. To do this, the cylinders are placed with different skew angles with respect to each other in order to emulate the effect of orientation. The maximum adhesion force and the size of the contact zone are determined experimentally under the action of surface energy. The difference of the maximum adhesion force between experiments and theory is found to increase as the contact area goes from mildly elliptical to slim elliptical contact. Similarly, it is observed that the contact area can be approximated to have elliptical geometry for a wide range of skew angles while a deviation is observed for slim elliptical contacts. Moreover, the reduction in the contact area is observed to be nonself-similar during detachment from an elliptical shape to a circular one.
EPR detected polarization transfer between Gd3+ and protons at low temperature and 3.3 T: The first step of dynamic nuclear polarization
Authors: Nagarajan Vijayasarathi , Hovav Yonatan , Feintuch Akiva , Vega Shimon , Goldfarb Daniella
Published: June 2010

Electron-electron double resonance pulsed electron paramagnetic resonance (EPR) at 95 GHz (3.3 T) is used to follow the dynamics of the electron spin polarization during the first stages of dynamic nuclear polarization in solids. The experiments were performed on a frozen solution of Gd+3 (S=7/2) in water/glycerol. Focusing on the central |−1/2⟩→|+1/2⟩ transition we measured the polarization transfer from the Gd3+ electron spin to the adjacent H1 protons. The dependence of the echo detected EPR signal on the length of the microwave irradiation at the EPR “forbidden” transition corresponding to an electron and a proton spin flip is measured for different powers, showing dynamics on the microsecond to millisecond time scales. A theoretical model based on the spin density matrix formalism is suggested to account for this dynamics. The central transition of the Gd3+ ion is considered as an effective S=1/2 system and is coupled to H1 (I=1/2) nuclei. Simulations based on a single electron-single nucleus four level system are shown to deviate from the experimental results and an alternative approach taking into account the more realistic multinuclei picture is shown to agree qualitatively with the experiments.
A field-cycle-induced high-dielectric phase in ferroelectric copolymer
Authors: Zaitsu Koichiro , Lee Sunghoon , Ishibe Kiyoshiro , Sekitani Tsuyoshi , Someya Takao
Published: June 2010

We report phase transitions from ferroelectric to paraelectric states that are induced in poly(vinylidene fluoride-trifluoroethylene) by electric field cycles. The transitions are systematically characterized electrically and structurally by using ferroelectric capacitors. The top electrodes of the capacitors can be peeled off from the surfaces of ferroelectric layers; this enables us to obtain clear x-ray diffraction patterns with adequate strength. The diffraction patterns clearly indicate the emergence of the stable phase, in which copolymer molecules are aligned with their b-axis perpendicular to the substrate. The dipoles become nonswitchable without changing the molecular structure. The new field-cycle-induced phase, which has high permittivity in the out-of-plane direction due to anisotropic molecular structures, is identified as the main mechanism of polarization fatigue.
Interplay of defects in 1.2 MeV Ar irradiated ZnO
Authors: Chattopadhyay Soubhik , Dutta Sreetama , Jana D. , Chattopadhyay S. , Sarkar A. , Kumar P. , Kanjilal D. , Mishra D. K. , Ray S. K.
Published: June 2010

Defect characterization in 1.2 MeV Ar8+ irradiated polycrystalline ZnO has been carried out by x-ray diffraction (XRD), scanning electron microscopy (SEM) along with electrical resistivity, and photoluminescence (PL) measurements at room temperature (RT). Interestingly, irradiation with the initial fluence (1×1015 ions/cm2) changes the color of the sample from white to orange while the highest irradiation fluence (5×1016 ions/cm2) makes it dark reddish brown that appears as black. XRD study reveals no significant change in the average grain size of the samples with irradiation fluence. Increase in surface roughness due to sputtering is clearly visible in SEM with highest fluence of irradiation. RT PL spectrum of the unirradiated sample shows intense ultraviolet (UV) emission (∼3.27 eV) and less prominent defect level emissions (2–3 eV). The overall emission is largely quenched due to initial irradiation fluence. Increasing the fluence of Ar beam further, UV emission is enhanced along with prominent defect level emissions. Remarkably, the resistivity of the irradiated sample with highest fluence is reduced by four orders of magnitude compared to that of the unirradiated sample. This is due to an increase in donor concentration as well as their mobility induced by high fluence of irradiation. Change in color in the irradiated samples indicates dominant presence of oxygen vacancies. It is now well known that oxygen vacancies are deep donors in ZnO. So oxygen vacancies, in principle, are not the source of conductivity in ZnO at RT. Simultaneous evolution of coloration and conductivity in ZnO, as is seen in this study, indicate that oxygen vacancies strongly influence the stability of shallow donors, presumably zinc interstitial related (highly mobile Zn interstitials also need to form defect pair/complex to be stable), which act as major source of carriers. Such a contention is in conformity with most recent theoretical calculations.
Martensitic transformation and accompanying magnetic changes in Ni–Fe–Ga–Co alloys
Authors: Sofronie Mihaela , Tolea Felicia , Kuncser Victor , Valeanu Mihaela
Published: June 2010

Two series of cobalt substituted Ni–Fe–Ga ferromagnetic shape memory alloys with lower gallium content (<27 at. %) were studied by differential scanning calorimetry, x-ray diffraction, and thermomagnetic measurements. Co substitution for Fe or Ni promotes an increase in the Curie temperatures and a variation in the martensitic transformation (MT) temperatures, in accord with the alloy valence electron concentration change. For alloys with MTs below room temperature, a field dependent thermomagnetic hysteresis was evidenced and discussed in connection with the effect of cobalt substitution, on the magnetic hardness of the martensite phase. A direct interpretation of the evolution of the thermomagnetic hysteresis versus the applied field was provided.
Strategies and tolerances of spin transfer torque switching
Authors: Nikonov Dmitri E. , Bourianoff George I. , Rowlands Graham , Krivorotov Ilya N.
Published: June 2010

Schemes of switching memories based on magnetic tunnel junctions via the effect of spin torque with various polarizations of injected electrons are studied. Simulations based on macrospin and micromagnetic theories without account of thermal fluctuations are performed and compared. We demonstrate that short-pulse precessional switching with perpendicularly polarized current requires a shorter time and smaller energy than switching with collinear in-plane spin polarization. We also show that memory cells based on precessional switching are superior to those in current technologies. We study the dependence of switching on the magnitude of current and pulse duration. An increased Gilbert damping is found to improve tolerances of perpendicular-polarization switching without increasing the threshold current, unlike in-plane switching.
Effects of concentration on structure, dielectric, and dynamic properties of aqueous NaCl solutions using a polarizable model
Authors: Sala J. , Guàrdia E. , Martí J.
Published: June 2010

The study of NaCl solutions in water at finite concentration, explicitly including polarization in water molecules and ions, has been carried out by molecular dynamics simulations. A comparison of the RPOL polarizable model with the rigid SPC/E potential for water has been included. Structure obtained with the two models does not show significant differences, although some deviations in the NaNa radial distribution functions at all concentrations are observed. Dielectric properties such as total and molecular dipole moment correlation functions revealed decay times of the order of 10 ps, roughly independent of concentration. The analysis of electric conductivity by means of current-current correlation functions also included the calculation of cross terms corresponding to dipole moment-current correlations, which proved to be non-neglectable at short times and especially relevant at high concentrations (m=4 mol kg−1). Frequency dependent dielectric constants and conductivities have been computed and the role of cross correlations has been analyzed. In all cases both concentration and cross correlations have significant influence in the results.
Delocalized water and fluoride contributions to Dyson orbitals for electron detachment from the hydrated fluoride anion
Authors: Canuto Sylvio , Coutinho Kaline , Cabral Benedito J. C. , Zakrzewski V. G. , Ortiz J. V.
Published: June 2010

The experimental vertical electron detachment energy (VEDE) of aqueous fluoride, [F−(H2O)], is approximately 9.8 eV, but spectral assignment is complicated by interference between F− 2p and H2O 1b1 orbitals. The electronic structure of [F−(H2O)] is analyzed with Monte Carlo and ab initio quantum-mechanical calculations. Electron-propagator calculations in the partial third-order approximation yield a VEDE of 9.4 eV. None of the Dyson orbitals corresponding to valence VEDEs consists primarily of F 2p functions. These results and ground-state atomic charges indicate that the final, neutral state is more appropriately described as [F−(H2O)+] than as [F(H2O)].
Atomic layer deposited silicon dioxide films on nanomechanical silicon nitride resonators
Authors: Waggoner P. S. , Tan C. P. , Craighead H. G.
Published: June 2010

Thin silicon dioxide films are deposited on nanomechanical resonators using atomic layer deposition (ALD), and their effect on the resonant properties of silicon nitride devices is studied as a function of thickness. We present experimental data and an analytical model for the effect of ALD growth and corroborate the model by studying resonators coated with atomic layer deposited aluminum nitride as well. As thicker films are deposited, device frequency shifts, become nonlinear with thickness, and quality factors drop significantly. Thin silicon dioxide coatings can be deposited on virtually any device surface to support surface chemistries commonly used in biochemical functionalization on glass surfaces. We also demonstrate that the efficiency of silane functionalization improves by 35% when low stress silicon nitride surfaces are coated with only 2.1 nm of atomic layer deposited silicon dioxide. This ALD modification technique should be particularly useful for nanomechanical resonant sensors since a thin, conformal film does not drastically reduce quality factor nor does it add excessive mass that would decrease device sensitivity.
Direct evaluation of low-field mobility and access resistance in pentacene field-effect transistors
Authors: Xu Yong , Minari Takeo , Tsukagoshi Kazuhito , Chroboczek J. A. , Ghibaudo Gerard
Published: June 2010

Organic field-effect transistors (OFETs) suffer from limitations such as low mobility of charge carriers and high access resistance. Direct and accurate evaluation of these quantities becomes crucial for understanding the OFETs properties. We introduce the Y function method (YFM) to pentacene OFETs. This method allows us to evaluate the low-field mobility without the access or contact resistance influence. The low-field mobility is shown to be more appropriate than the currently applied field-effect mobility for the OFETs’ performance evaluation. Its unique advantage is to directly suppress the contact resistance influence in individual transistors, although such contact resistance is a constant as compared to the widely accepted variable one with respect to the gate voltage. After a comparison in detail with the transmission-line method, the YFM proved to be a fast and precise alternative method for the contact resistance evaluation. At the same time, how the contact resistance affects the effective mobility and the field-effect mobility in organic transistors is also addressed.
The interaction of MnH(X Σ7+) with He: Ab initio potential energy surface and bound states
Authors: Turpin Florence , Halvick Philippe , Stoecklin Thierry
Published: June 2010

The potential energy surface of the ground state of the He–MnH(X Σ7+) van der Waals complex is presented. Within the supermolecular approach of intermolecular energy calculations, a grid of ab initio points was computed at the multireference configuration interaction level using the aug-cc-pVQZ basis set for helium and hydrogen and the relativistic aug-cc-pVQZ-DK basis set for manganese. The potential energy surface was then fitted to a global analytical form which main features are discussed. As a first application of this potential energy surface, we present accurate calculations of bound energy levels of the H3e–MnH and H4e–MnH complexes.
Optical performance of single-mode hybrid dielectric-loaded plasmonic waveguide-based components
Authors: Chu Hong-Son , Li Er-Ping , Bai Ping , Hegde Ravi
Published: June 2010

The single mode hybrid dielectric-loaded plasmonic waveguide is presented at the wavelength of 1.55 μm. We show that this waveguiding structure, consisting of a low-index SiO2-stripe sandwiched between a high-index Si-nanowire and a silver film, achieves both long propagation length and strong field confinement with high power intensity. Components such as 90°-circular and S-shaped bends, based on the proposed waveguide with an intensity confinement area of 50×200 nm2, can obtain a total transmission efficiency exceeding 85% for various bend radii. Finally, we demonstrate that the efficient directional couplers can be developed using two coupled waveguides. In particular, we determine the typical coupling lengths and maximum transfer power for different structural parameters of the coupler. These investigations provide the foundations for the design of chip-scale integrated plasmonic circuitry.
Free-standing subwavelength metallic gratings for snapshot multispectral imaging
Authors: Haïdar Riad , Vincent Grégory , Collin Stéphane , Bardou Nathalie , Guérineau Nicolas , Deschamps Joël , Pelouard Jean-Luc
Published: June 2010

A mosaic of ten spectral filters has been fabricated in a single 20 mm2 membrane drilled by nanoslits and coated by a gold layer. The nanostructured core-shell gratings exhibit 70% average maximum transmission efficiency in 15% aperture area, which represents a fivefold enhancement compared to the geometrical transmission. This mosaic of bandpass filters regularly spaced in the 3–5 μm wavelength range is used to demonstrate real-time spectral imaging in a multichannel camera.
Optical chirality of bacteriorhodopsin films via second harmonic Maker’s fringes measurements
Authors: Larciprete M. C. , Belardini A. , Sibilia C. , Saab M.-b. , Váró G. , Gergely C.
Published: June 2010

We experimentally investigated second harmonic generation from an oriented multilayer film of bacteriorhodopsin protein, deposited onto a charged surface. The generated signal is obtained as a function of incidence angle, at different polarization state of both fundamental and generated beams. We show that the measurements, together with the analytical curves, allow to retrieve the nonvanishing elements of the nonlinear optical tensor, including the ones introduced by optical chirality.
Synthesis and characterization of CsSnI3 thin films
Authors: Shum Kai , Chen Zhuo , Qureshi Jawad , Yu Chonglong , Wang Jian J. , Pfenninger William , Vockic Nemanja , Midgley John , Kenney John T.
Published: June 2010

We report on the synthesis and characterization of CsSnI3 perovskite semiconductor thin films deposited on inexpensive substrates such as glass and ceramics. These films contained polycrystalline domains with typical size of 300 nm. It is confirmed experimentally that CsSnI3 compound in its black phase is a direct band-gap semiconductor, consistent with the calculated band structure from the first principles. The band gap is determined to be ∼1.3 eV at Γ point at room temperature.
Role of nuclear tubule on the apoptosis of HeLa cells induced by femtosecond laser
Authors: He Hao , Chan Kam Tai , Kong Siu Kai
Published: June 2010

It was found that nuclear tubules (NTs) would develop inside the nuclei of HeLa cells when they were irradiated by a femtosecond laser at the wavelength of 1554 nm for 40 s or longer. These NTs provided a pathway for the excess calcium generated by the laser to diffuse from the cytoplasm to the nucleus. Concurrently, the NTs served to spread mitochondria deep inside the nucleus so that they could initiate DNA fragmentations in regions covered by the NTs in the apoptotic cell. The role of NT as the precursor and passage to apoptosis is firmly established.
Ideal gas thermodynamic properties of six fluoroethanes
Authors: Chen S. S. , Rodgers A. S. , Choo J. , Wilhoit R. C. , Zwolinski B. J.
Published: June 2010

The molecular structural parameters, the vibrational fundamentals, the potential barrier height to internal rotation, and the standard enthalpy of formation for each of the six fluoroethanes in which at least one of the internally rotating groups is a symmetric top have been extensively studied and recommended values selected. Chemical thermodynamic properties of molecules in the ideal gas state at temperatures from 0 to 1500 K have been calculated with the rigid-rotor harmonic-oscillator approximation. The calculated values are in very good agreement with the existing third-law entropies.
Ideal gas thermodynamic properties of the eight bromo- and lodomethanes
Authors: Kudchadker S. A. , Kudchadker A. P.
Published: June 2010

The available molecular parameters, fundamental frequencies, and enthalpy of formation for eight bromo- and indomethanes have been critically evaluated and recommended values selected. This information has been utilized to calculate the ideal gas thermodynamic properties. C°p, S°, H°−H°0, (G°−H°0)/T, ΔHℱ°, ΔGℱ°, and log Kℱ from 0 to 1500 K using the rigid rotor-harmonic oscillator approximation.
Molten salts: Volume 4, part 2, chlorides and mixtures—electrical conductance, density, viscosity, and surface tension data
Authors: Janz G. J. , Tomkins R. P. T. , Allen C. B. , Downey J. R. , Garner G. L. , Krebs U. , Singer S. K.
Published: June 2010

Data on the electrical conductance, density, viscosity, and surface tension chloride mixtures have been systematically collected and evaluated. results are given in 124 binary mixtures over a range of compositions and temperatures. Values of the above properties for the single salts have been updated in accord with previously advanced recommendations.
Diffusion in copper and copper alloys part IV. Diffusion in systems involving elements of group VIII
Authors: Butrymowicz Daniel B. , Manning John R. , Read Michael E.
Published: June 2010

A survey, comparison, and critical analysis is presented of data compiled from the scientific literature concerning diffusion in copper alloy systems involving elements in Group VII (Co, Fe, Ni, Pd, Pt, Rh, Ru). Here the term ’’copper alloy system’’ is interpreted in the broadest sense. For example, the review of diffusion in the Cu-M system reports all diffusion situations which involve both copper and element M. including diffusion of Cu in M or in any binary, ternary or multicomponent alloy containing M; diffusion of M in Cu or in any alloy containing Cu; and diffusion of any element in any alloy containing both Cu and M. Topics include volume diffusion, surface diffusion, grain boundary diffusion, tracer diffusion, alloy interdiffusion, electromigration, thermomigration, dislocation-pipe diffusion, and diffusion in molten metals. An extensive bibliography is presented along with figures, tabular presentation of data and discussion of results.
Refractive index of alkali halides and its wavelength and temperature derivatives
Authors: Li H. H.
Published: June 2010

Refractive index data for 20 alkali halides are exhaustively surveyed, compiled, and analyzed. The most probable values at 293 K for the transparent region are generated for the materials for which experimental data are sufficiently abundant and reliable. Provisional values are also provided for the wavelength regions where available data are insufficient or missing. Reasonable estimations of refractive index for the very scantily measured materials were made by incorporating the dielectric constants and wavelengths of absorption peaks into a simplified dispersion equation. Temperature derivatives of refractive index for most of the alkali halides were unavailable. However, using the existing data for the five most commonly used alkali halides, novel empirical facts were discovered and dn/dT formulas were constructed for all of the alkali halides. The calculated dn/dT values agree remarkably well with the existing experimental data.
Microwave spectra of molecules of astrophysical interest. XVIII. Dimethyl ether
Authors: Lovus F. J. , Lutz H. , Dreizler H.
Published: June 2010

The microwave spectra of dimethyl ether (methoxymethane) is critically reviewed and supplemented through calculations which include the contributions of internal rotation and centrifugal distortion in the molecular Hamiltonian. The primary objective of this review is to provide microwave spectral transitions applicable to molecular radio astronomy for the ground vibrational state rotational spectrum of the most abundant isotopic form of dimethyl ether, 12CH316O12CH3. While all measured rotational transitions are included, the predicted transition frequencies were limited to J?15 in the range 1 GHz to 300 GHz. In order to provide a complete summary of the laboratory studies on dimethyl ether, the rotational constants of the less abundant isotopic species and excited torsional states are also tabulated and all reported rotational studies are referenced.
Evaluated activity and osmotic coefficients for aqueous solutions: iron chloride and the bi-univalent compounds of nickel and cobalt
Authors: Goldberg R. N. , Nuttall R. L. , Staples B. R.
Published: June 2010

A critical evaluation of the mean activity and osmotic coefficients in aqueous solutions of iron chloride, nickel chloride, perchlorate, and nitrate and twenty-nine bi-univalent compounds of cobalt at 298.15 K is presented. Osmotic coefficients were calculated from direct vapor pressure measurements, from isopiestic measurements, from freezing point depression measurements, and from vapor pressure osmometry measurements. Given are empirical coefficients for three different correlating equations, obtained by a weighted least squares fit of the experimental data, and tables consisting of the activity coefficients of the compounds, the osmotic coefficients and activity of water, and the excess Gibbs energy of the solution as functions of the molality for each electrolyte system. The literature coverage is through the computerized version of Chemical Abstracts of April 1979.
Evaluated activity and osmotic coefficients for aqueous solutions: Bi-univalent compounds of zinc, cadmium, and ethylene bis(trimethylammonium) chloride and iodide
Authors: Goldberg R. N.
Published: June 2010

A critical evaluation of the mean activity and osmotic coefficients in aqueous solutions of eleven bi-univalent compounds of zinc and cadmium and ethylene bis(trimethylammonium) chloride and iodide at 298.15 K is presented. Osmotic coefficients were calculated from direct vapor pressure measurements, from isopiestic measurements and from freezing point depression measurements. Activity coefficients were calculated from electromotive force measurements on galvanic cells with and without transference. Given are empirical coefficients for three different correlating equations, obtained by a weighted least squares fit of the experimental data, and tables consisting of the activity coefficients of the compounds, the osmotic coefficients and activity of water, and the excess Gibbs energy of the solution as functions of the molality for each electrolyte system. The literature coverage is through the computerized version of Chemical Abstracts of September 1979.
Heat capacity and other thermodynamic properties of linear macromolecules. I. Selenium
Authors: Gaur Umesh , Shu Hua-Cheng , Mehta Aspy , Wunderlich Bernhard
Published: June 2010

The heat capacity of selenium from 0 K to 1000 K is reviewed using measurements on 20 samples reported in the literature. A set of recommended data for trigonal, monoclinic, glassy, and molten selenium is derived. Ring-chain equilibrium parameters are critically evaluated. Entropy, enthalpy, and Gibbs energy functions are calculated. Selenium is a model compound for a monoatomic, linear macromolecule. This paper is first in a series which will ultimately cover all heat capacity measurements on linear macromolecules.
Activity and osmotic coefficients of aqueous alkali metal nitrites
Authors: Staples Bert R.
Published: June 2010

A critical evaluation of the mean activity γ±, and osmotic coefficients, φ, of aqueous alkali metal nitrites at 298.15 K is presented for the molality range from dilute to saturation. Osmotic coefficients were calculated from static vapor pressure measurements. A nonlinear least-squares program was used to fit φ data as a function of molality. Several equations describe the osmotic coefficient, the mean activity coefficient, and the excess Gibbs energy as a function of the square-root of molality for each slit. The scientific literature was covered through March 1979.
Heat capacity and other thermodynamic properties of linear macromolecules. III. Polyoxides
Authors: Gaur Umesh , Wunderlich Bernhard
Published: June 2010

The heat capacity of poly(oxymethylene), poly(oxyethylene), poly(oxytrimethylene), poly(oxytetramethylene), poly(oxyoctamethylene), poly(oxypropylene), Poly(oxymethyleneoxyethylene), poly(oxymethyleneoxytetramethylene), poly(oxy-1,4-phenylene), poly(oxy-2,6-dimethyl-1,4-phenylene), ploy(oxy-2,6-diphenyl-1,4-phenylene) and poly[oxy-2,2-bis(chloromethyl)trimethylene] is reviewed on the basis of measurements on 35 samples reported in the literature. The crystallinity dependence is critically evaluated and a set of recommended data for each polyoxide is derived. Entropy, enthalpy, and Gibbs energy functions are calculated. The data have been compared to that of polyethylene and the contribution of -O-group has been evaluated. This paper is the third in a series which will ultimately cover all heat capacity measurements on linear macromolecules.
Heat capacity and other thermodynamic properties of linear macromolecules. IV. Polypropylene
Authors: Gaur Umesh , Wunderlich Bernhard
Published: June 2010

The heat capacity of polypropylene from 0 K to 600 K is reviewed on the basis of measurements on 20 samples reported in the literature. The crystallinity dependence is critically evaluated and a set of recommended data for completely crystalline and amorphous polypropylene are derived. The effect of tacticity on the heat capacity is also evaluated. Entropy, enthalpy, and Gibbs energy functions are calculated. This paper is the fourth in a series of publications which will ultimately cover all heat capacity measurements on linear macromolecules.
A critical review of Henry’s law constants for chemicals of environmental interest
Authors: Mackay Donald , Shiu Wan Ying
Published: June 2010

The Henry’s law constants (air-water partition coefficients) of hydrophobic organic compounds of environmental concern are reviewed. An outline of the thermodynamic principles which govern the relationships between vapor pressure, solubility and Henry’s law constant for solid and liquid compounds is presented and experimental techniques for obtaining these quantities with the required accuracy are discussed. Vapor pressure, solubility, and Henry’s law constant data are tabulated and reviewed for a total of 150 compounds in 12 tables consisting of gaseous, liquid and solid alkanes, cycloalkanes, alkenes, alkynes, monoaromatics, polynuclear aromatics, halogenated alkanes, alkenes and aromatics, and selected pesticides.
Peak Absorption Coefficients of Microwave Absorption Lines of Carbonyl Sulphide
Authors: Kisiel Z. , Millen D. J.
Published: June 2010

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.
Vibrational Contributions to Molecular Dipole Polarizabilities
Authors: Bishop David M. , Cheung Lap M.
Published: June 2010

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.
A Fundamental Equation of State for Heavy Water
Authors: Hill P. G. , MacMillan R. D. Chris , Lee V.
Published: June 2010

A fundamental equation of state has been formulated for heavy water in the form Ψ = Ψ(p,T) in which Ψ = Helmholtz free energy p = 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 PvT 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.
Evaluation of Binary Excess Enthalpy Data for C6 Hydrocarbons. Benzene+Cyclohexane
Authors: Smith Buford D. , Muthu Ol , Dewan Ashok , Gierlach Matthew
Published: June 2010

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.
Heat Capacity and Other Thermodynamic Properties of Linear Macromolecules. IX. Final Group of Aromatic and Inorganic Polymers
Authors: Gaur Umesh , Lau Suk-fai , Wunderlich Bernhard
Published: June 2010

In this final review, a series of polymers which include aromatic rings and/or inorganic chain atoms are treated. Heat capacities of poly(4,4′-isopropylidenediphenylene carbonate), polyphenylenediamides, polyheteroarylenes, poly(dimethyl siloxane), poly(diethyl siloxane), poly(trimethylsilyl ethylene), poly(dimethylphenylsilyl ethylene), poly(dimethylbenzylsilyl ethylene), poly(vinylene diphenylsilylene), poly(vinylene diphenylgermylene), poly(diethnyl diphenysilylene), poly(diethnyl diphenylgermylene), poly(2,3,4,5-tetraphenyl-1, 1-diethylgermocyclopentadiene), poly(phenylsilsesquioxane), poly[ethylene -N-(β-trimethylsilylethyl)imine] and polysulfones have been reviewed on the basis of measurements on 36 samples reported in the literature. All heat capacity data are compiled and a set of recommended data are derived. Enthalpy and entropy functions are calculated for poly(4,4′-isopropylidenediphenylene carbonate) and poly(dimethyl siloxane).
Molten Salts: Volume 5, Part 2. Additional Single and Multi-Component Salt Systems. Electrical Conductance, Density, Viscosity and Surface Tension Data
Authors: Janz G. J. , Tomkins R. P. T.
Published: June 2010

Evaluated data for the four properties, density, surface tension, viscosity, and electrical conductance are reported for salt systems in which the anionic and cationic species may differ. This contrasts with the systems in the preceding publications in this series in which the anionic species were, in general, the same in the binary mixtures. The results are reported in equation form, with brief tables of numerical values. A cross index by salt system was compiled and is included for ease of accessing the data tables.
High Temperature Vaporization Behavior of Oxides. I. Alkali Metal Binary Oxides
Authors: Lamoreaux R. H. , Hildenbrand D. L.
Published: June 2010

In order to assess the high temperature vaporization behavior and equilibrium gas phase compositions of binary alkali metal oxides, the relevant thermodynamic and molecular constant data have been compiled and critically evaluated. Selected values of the Gibbs energy and enthalpy functions of condensed and vapor phases are given in the form of equations valid over wide temperature ranges, along with the standard entropies and enthalpies of formation. These data were used to generate plots of the equilibrium partial pressures of vapor species as functions of temperature for representative conditions ranging from reducing to oxidizing. Maximum vaporization rates have been calculated using the Hertz–Knudsen equation. Literature references are given.
Water Solubilities of Polynuclear Aromatic and Heteroaromatic Compounds
Authors: Pearlman Robert S. , Yalkowsky Samuel H. , Banerjee Sujit
Published: June 2010

The water solubilities of several polynuclear aromatic and heteroaromatic hydrocarbons have been compiled and reviewed for consistency through correlations with parameters such as surface area, molecular volume, and boiling point. The carbocycles and oxygen and sulfur heterocycles were governed by the same correlative equations, thereby indicating that these heteroatoms entered into only a limited degree of hydrogen bonding. Equations representing the nitrogen heterocycles differed from their carbocyclic counterparts by an approximately constant amount, suggesting that while the solubilizing effect of the nitrogen heteroatom may be large, it tends to remain constant within a similar series of compounds.
The Solubility of Nitrogen and Air in Liquids
Authors: Battino Rubin , Rettich Timothy R. , Tominaga Toshihiro
Published: June 2010

This review covers the solubility of nitrogen and air in liquids as a function of temperature and pressure. Solubility data for individual systems were critically evaluated. Recommended or tentative values are presented as smoothing equations and/or in tabular form. Trends in homologous series or related solvents are discussed. Data for the n-alkanes were smoothed with respect to temperature, pressure, and carbon number. Liquids include: water; heavy water; seawater; aqueous salt solutions; mixed solvents; hydrocarbons; organic compounds containing oxygen, halogen, sulfur, nitrogen, or silicon; olive oil; various biological fluids; H2S; SO2; NH3; CO2; nitrogen oxides; and several halogen and boron containing inorganic solvents.
Experimental Stark Widths and Shifts for Spectral Lines of Positive Ions (A Critical Review and Tabulation of Selected Data for the Period 1976 to 1982)
Authors: Konjević N. , Dimitrijević M. S. , Wiese W. L.
Published: June 2010

A new critical review of the available experimental data on the Stark widths and shifts for lines of non-hydrogenic ionized spectra has been carried out which covers the period from 1976 to the present and represents a continuation of an earlier critical review. The relevant literature, compiled by the NBS Data Center on Atomic Lines Shapes and Shifts as well as by the present authors, was critically evaluated, and data tables containing the selected experimental Stark broadening parameters have been assembled. The data are arranged according to spectra and elements and these are presented in alphabetical order. The accuracy of the experimental data is estimated on the basis of guidelines developed during the previous review. Comparisons with theoretical results are made whenever possible since the comparison with theory has often been a principal motivation for the experiments.
Ground-State Vibrational Energy Levels of Polyatomic Transient Molecules
Authors: Jacox Marilyn E.
Published: June 2010

The experimentally determined ground-state vibrational energy levels of approximately 480 covalently bonded transient molecules possessing from 3 to 16 atoms are tabulated, together with references to the pertinent literature. The types of measurement surveyed include laser-based high resolution gas phase infrared absorption and visible-ultraviolet emission techniques, ultraviolet photoelectron spectroscopy, and matrix isolation spectroscopy. An assessment of the magnitude of the uncertainty of observations in neon, argon, and nitrogen matrices is given.
Evaluation of the Thermodynamic Functions for Aqueous Sodium Chloride from Equilibrium and Calorimetric Measurements below 154 °C
Authors: Clarke E. Colin W. , Glew David N.
Published: June 2010

A new weighted least-squares method is described which is generally applicable for the nonsubjective evaluation of the best set of thermodynamic functions from a given data set of equilibrium (ΔG) and calorimetric (ΔH, Cp) measurements. The method, applied to model a wide range of 2428 measurements for the water-sodium chloride system between −21 and 154 °C, accurately represents all measurements within experimental error. The resulting model is used to predict the thermodynamic functions and their standard errors for aqueous sodium chloride up to 110 °C. Tables are given for freezing point, solubility, boiling point, osmotic and activity coefficients, vapor pressure, apparent molal relative enthalpy, partial molal relative enthalpies, integral heat of solution, specific heat, apparent molal heat capacity, partial molal heat capacities, apparent molal relative heat capacity, partial molal relative heat capacities, standard thermodynamic functions, and their changes for dissolution.
The Electronic Spectrum and Energy Levels of the Deuterium Molecule
Authors: Freund Robert S. , Schiavone James A. , Crosswhite H. M.
Published: June 2010

Beginning in the 1930s, G.H. Dieke and his students carried out an extensive program of measuring the optical spectrum of molecular hydrogen and its isotopes. Parts of the work were published but the project was interrupted by Dieke’s death in 1965, with much of the latest and most accurate work unpublished. This paper gives the 27 488 lines of molecular deuterium, measured by Dieke, arranges the 8243 assigned lines into band systems, and derives rotational–vibrational energy levels for over 50 electronic states. It also derives energy levels from published vacuum ultraviolet spectra of D2.
Cross Sections for Collisions of Electrons and Photons with Nitrogen Molecules
Authors: Itikawa Y. , Hayashi M. , Ichimura A. , Onda K. , Sakimoto K. , Takayanagi K. , Nakamura M. , Nishimura H. , Takayanagi T.
Published: June 2010

Data have been compiled on the cross sections for collisions of electrons and photons with nitrogen molecules (N2). For electron collisions, the processes considered are: total scattering, elastic scattering, momentum transfer, excitations of rotational, vibrational and electronic states, dissociation, and ionization. Ionization and dissociation processes are discussed for photon impact. Cross section data selected are presented graphically. Spectroscopic and other properties of the nitrogen molecule are summarized. The literature was surveyed through the end of 1984, but some more recent data are included when useful.
Rate Constants for Reactions of Radiation-Produced Transients in Aqueous Solutions of Actinides
Authors: Gordon S. , Sullivan J. C. , Ross Alberta B.
Published: June 2010

Rate constants have been critically compiled for reactions of ions of the actinides Am, Cf, Cm, Np, Pu, Th, and U, as well as the element Tc, in different oxidation states with various chemical species in aqueous solution. The reactants include products of the radiolysis of water (hydrated electrons, hydrogen atoms, hydroxyl radicals, hydrogen peroxide) and transient species derived from other solutes (e.g., carbonate radical). The data are useful in the estimation of migration properties of actinides, which are relevant to waste management studies.
Triplet–Triplet Absorption Spectra of Organic Molecules in Condensed Phases
Authors: Carmichael Ian , Hug Gordon L.
Published: June 2010

We present a compilation of spectral parameters associated with triplet–triplet absorption of organic molecules in condensed media. The wavelengths of maximum absorbance and the corresponding extinction coefficients, where known, have been critically evaluated. Other data, for example, lifetimes, energies and energy transfer rates, relevant to the triplet states of these molecules are included by way of comments but have not been subjected to a similar scrutiny. Work in the gas phase has been omitted, as have theoretical studies. We provide an introduction to triplet state processes in solution and solids, developing the conceptual background and offering an historical perspective on the detection and measurement of triplet state absorption. Techniques employed to populate the triplet state are reviewed and the various approaches to the estimation of the extinction coefficient of triplet–triplet absorption are critically discussed. A statistical analysis of the available data is presented and recommendations for a hierarchical choice of extinction coefficients are made. Data collection is expected to be complete through the end of 1984. Compound name, molecular formula and author indexes are appended.
Forbidden Lines in n
s2n
p
k Ground Configurations and n
s
n
p Excited Configurations of Beryllium through Molybdenum Atoms and Ions
Authors: Kaufman Victor , Sugar Jack
Published: June 2010

Observed and predicted wavelengths of magnetic dipole lines arising within ground configurations of the type ns2npk(n=2 and 3, k=1 to 5) are compiled. For n=2 the compilation includes the elements B through Kr, and for k=5 it extends to Mo. For n=3 Al through Mo are included. In addition the 2s2p excited configuration of the Be i isoelectronic sequence for Be through Kr and 3s3p of the Mg sequence for Mg through Mo are included. For each line we give a calculated value for the transition probability obtained mainly from the Dirac-Fock method or from the use of scaled radial integrals. The calculated wavelengths are obtained from known energy levels or from levels derived from scaled radial integrals. A small group of electric quadrupole lines seen in astronomical sources are included. The list contains 1660 predicted wavelengths in the range 100 Å to 25.9 mm and 406 observed wavelengths in the range 325 Å to 609 μm.