bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic Study of Some Organo-Metallic Compounds of Arsenic
Authors: Prasad Mata , Mulay L. N.
Published: January 2005

The susceptibility of As has been evaluated from the molecular susceptibilities of organo-metallic compounds of the type (i) R.AsH2, R3As, (ii) R—As:As—R, (iii) RAs:O(OH)2, R2As:O(OH), and R3As(OH)2, using Pascal's constants for atoms and linkages in the organic radicals R and those derived for :O and —OH groups in arsinic acids. The values obtained from (i) and (ii) are in agreement with Honda's value for arsenic element. These values, and that deduced from (iii), are much different from Slater's theoretical value for the As atom.

In the (i) arsines, (ii) arseno-compounds, and (iii) arsinic acids, a distinct linear relationship has been observed between the molecular susceptibility and the total number of electrons in the molecule. The linear relation has been used to evaluate the susceptibility of the As atom in these compounds, which is in agreement with Slater's theoretical value.
Diffusion through an Interface
Authors: Scott E. J. , Tung L. H. , Drickamer H. G.
Published: January 2005

The diffusion equation has been solved for the case of two cells of finite length with an interface between the cells. The effect of an interfacial resistance to mass transfer has been considered. It is shown that the situation where there is equilibrium (no resistance) at the interface is a special case of our solution. Several important cases are considered numerically.
Force Constants and Calculated Thermodynamic Properties for SiF4
Authors: Voelz Fred L. , Meister Arnold G. , Cleveland Forrest F.
Published: January 2005

Using observed fundamental frequencies and the Wilson FG matrix method, sets of force constants for SiF4 have been determined using the most general second degree potential energy function. While no unique set of force constants can be given, limits are set for the force constants. Also the calculations indicate that if the Si–F bond interaction constant is ignored, too high a value for the Si–F bond stretching force constant results. Finally, the heat content, free energy, entropy, and heat capacity for the ideal gaseous state at 1 atmos pressure were calculated for 11 temperatures ranging from 100–1000°K, using a rigid rotator, harmonic oscillator approximation.
Microwave Spectroscopic Investigation of the Kinetics of the Heterogeneous Ammonia-Deuterium Exchange
Authors: Weber J. , Laidler Keith J.
Published: January 2005

A method is described for analyzing a mixture of gases using microwave spectroscopy. Relatively simple microwave measurements are employed on single resolved collision broadened spectral lines. For binary mixtures, only the peak absorption coefficients need to be measured if the microwave collision diameters are known. Mixtures of isotopically substituted molecules can also be analyzed because the microwave absorption lines of the isotopic species are easily resolved.

The technique is applied to determining the mole fraction of NH3 in mixtures of deuterated ammonias, and to a study of the kinetics of the NH3—D2 isotopic exchange reaction on a singly promoted iron catalyst. It is found that rates of desorption of molecules from surfaces are markedly increased on adsorption of other molecules, a fact that can be explained only in terms of strong interactions between adsorbed molecules. The rate of the exchange reaction is proportional to the square root of the deuterium pressure. With increasing ammonia pressure the rate passes through a maximum, showing that the mechanism involves reaction between adsorbed ammonia and adsorbed deuterium atoms. The activation energy diminishes significantly with increasing ammonia pressure, providing additional evidence for the existence of strong interactions between adsorbed molecules.
Studies on Tellurium-Selenium Alloys
Authors: Grison E.
Published: January 2005

Tellurium and metallic (hexagonal) selenium were shown to give solid solution in any concentration. The variation of the cell dimensions with composition departs only slightly from linearity: c shows a certain tendency to contraction (this corresponds to a smaller valency angle in the chains of atoms than is required by a linear variation): a varies much less (2 percent between Se and Te) and in a manner which depends upon the preparation of the alloy (as already observed for pure selenium by H. Krebs).

The presence of sharp (hk·l) lines with l≠0 in all the alloys suggests that these must be composed not of homogeneous chains (i.e., Se chains, Te chains packed together), but of composite chains, in which the homogeneous sequences must be fairly short.
Contact Distances of Ion Pairs in the Isomeric Dichloroethanes
Authors: Stern Kurt H. , Healey Frank , Martell Arthur E.
Published: January 2005

The effective dielectric constant of ethylene chloride is calculated from known dissociation constants of various ion pairs in ethylene and ethylidene chloride according to the method of Denison and Ramsey. The average value of the effective dielectric constant is used for the calculation of contact distances of various ion pairs in ethylene chloride. The variation of contact distance with size and structure of the ions is discussed.
The Analysis of the Infrared Spectrum of Chlorine Monofluoride
Authors: Nielsen Alvin H. , Jones Ernest A.
Published: January 2005

The vibration-rotation fine-structure of the fundamental and first overtone of ClF has been resolved with grating spectrometers utilizing an 1800 lines-per-inch and a 3600 lines-per-inch grating. An analysis of the observed bands is given and the ωe and xeωe for Cl35F19 and Cl37F19 were found to be 786.34 cm−1, 6.23 cm−1, and 778.82 cm−1, and 6.11 cm−1, respectively.
The Oscillator Strength of H2+, 1sσ—2pσ
Authors: Bates David R.
Published: January 2005

The 1sσ—2pσ transition of H2+ is investigated using exact two center wave functions and using approximate wave functions based on a linear combination of atomic orbitals (with both the dipole length and the dipole velocity formulas). It is found that at the equilibrium internuclear distance, 2.00 a0, the true oscillator strength of the transition is 0.319; with the dipole length formula, the LCAO approximation yields a value some 1.4 times greater, and with the dipole velocity formula it yields a value some 0.54 times smaller. Results are given for internuclear distances between 0 and 9 a0.
Asymptotic Expansion of the Partition Function of the Asymmetric Top
Authors: Stripp Kenneth F. , Kirkwood John G.
Published: January 2005

Methods developed by Wigner and Kirkwood for the determination of the partition functions of dynamical systems without explicit knowledge of the energy eigenvalues are used to calculate the first two terms of the asymptotic expansion of the partition function of the asymmetric top in powers of Planck's constant. The result is compared with Viney's expansion for the symmetric top and with Gordon's approximate expansion for the asymmetric top.
Theory of Anisotropic Colloidal Solutions
Authors: Isihara Akira
Published: January 2005

The appearance of anisotropic phase in the unipolar coacervations of tobacco mosaic virus or bentonite solutions are explained theoretically, and the recent theory of Onsager is confirmed. As has been emphasized already by Langmuir, the repulsive forces between solute molecules and the force arising from thermal agitation are decisive for the occurrence of the anisotropic phase. The critical concentrations where the anisotropic phase starts are explicitly determined for prolate and oblate spheroidal and also cylindrical solute molecules. It is found that the critical concentrations are all inversely proportional to the axial ratios, and therefore, it is explained why these critical concentrations are of the same order of magnitude in spite of the totally different characters of solute molecules
The Infrared Spectra of N-Acetylglycine and Diketopiperazine in Polarized Radiation at 25° and at −185°C
Authors: Newman Roger , Badger Richard M.
Published: January 2005

The infrared absorption spectra of single crystals of N-acetylglycine and of diketopiperazine have been observed at room temperature, and at −185°C, using polarized radiation. The spectrum of the former substance shows some remarkable changes with temperature. In both cases cooling produces a pronounced narrowing of the broad bands due to the vibration of hydrogen atoms involved in strong hydrogen bonds. The two spectra furnish examples of NH absorption in the two extremes of weak and very strong hydrogen bonding. In diketopiperazine two possible interpretations of the doublet structure in the NH valence band are offered
The Critical Field Curve in an Antiferromagnetic Crystal
Authors: Garrett C. G. B.
Published: January 2005

Van Vleck's theoretical model for the antiferromagnetic state is extended to describe the effect of applying magnetic fields so large that the Zeeman splitting is of the same order of magnitude as the exchange interaction. The intensity of magnetization, entropy, and Gibbs free energy are calculated. It is concluded that, when the field is applied parallel to the direction of the antiferromagnetic chains, the antiferromagnetic configuration (that in which there are two sublattices in the crystal possessing unequal magnetizations) is energetically favored for all values of H and T at which it is mathematically permissible. The boundary of the antiferromagnetic solution is a certain critical field curve in the H, T plane, ending at the Curie temperature TC on the T axis, and at a critical field HC on the H axis, related to TC by μHC/kTC=1. The case of perpendicular field, and the influence of next-to-nearest neighbor interaction, are also discussed. Comparison is made between the predictions of the theory and the results of recent experiments by the writer on critical field phenomena in cobalt ammonium sulfate at temperatures below 1°K. This theoretical treatment of exchange antiferromagnetism is contrasted with the theory of Sauer and Temperley on dipole-dipole interaction cooperative effects, which also predicts the existence of a critical curve. The possibility of observing critical field effects in other materials at much higher or much lower temperatures is also discussed.
Potential Energy Curve of the Excited State of LiH
Authors: Rosenbaum E. J.
Published: January 2005

A method developed by Klein has been applied to obtain the potential energy curve of the excited electronic state of LiH (state V). This curve crosses the Coulombic curve of Li+H— and indicates dissociation of excited LiH into Li(2P)+H. The effect of this behavior on Mulliken's explanation of the unusual shape of the state V curve is discussed. The interaction of the Li+H— and Li(2P)·H curves at moderately large interatomic distances is larger than Mulliken's estimate.
The Low Temperature Heat Capacity of Gaseous Ethane
Authors: Kistiakowsky G. B. , Nazmi Falih
Published: January 2005

The heat capacity of ethane has been determined at 163° and 143°K by the ``hot wire'' method and has been found not to level off as suggested earlier by Eucken and Weigert. This speaks against free interval rotation in ethane molecules.
The Thermodynamic Functions of the Chloro- and Bromomethanes, Formaldehyde and Phosgene
Authors: Stevenson D. P. , Beach J. Y.
Published: January 2005

By use of the harmonic oscillator-rigid rotator approximation the free energy function (F0—E00/T), and the heat content (H0—E00) of the chloro- and bromomethanes, formaldehyde and phosgene have been calculated from spectroscopic and electron diffraction data over temperature ranges where the aforesaid approximations are valid. The heat capacity Cp for the bromomethanes, formaldehyde and phosgene have been calculated over the same temperature range as the free energy function and the heat content. The entropies of the ten molecules in the hypothetical ideal gas state at 298.1°K have been calculated. With the values of (F0—E00/T) for β-graphite, chlorine, oxygen and hydrogen tabulated by other investigators with our values of this function for the chloromethanes, formaldehyde and phosgene and the heat data of Bichowsky and Rossini we have calculated the free energy of formation of these molecules.
Propagation of Sound in Gases
Authors: Saxton Harold L.
Published: January 2005

The propagation of sound and supersonic waves in gases has been attacked by Kneser, Richards and Reid, Rose, and others, without taking viscosity and heat conduction into account. Bourgin neglects viscosity. Herzfeld and Rice have taken heat conduction and viscosity into account along with the effect of internal temperature lag of one state. In the present paper, these effects are considered together with the effect of many internal energy states. The general equation is derived for wave propagation in a pure gas of any number of energy states. The probability constants involved are functions of temperature and gas composition only. This equation is first solved for the case of a single two state gas. The solution is then extended to mixtures of gases, including air.
The Absorption Spectra of Cyclopropane, Ethylene Oxide, Ethylene Sulfide, and Ethylene Imine in the Photographic Infra-Red
Authors: Eyster Eugene H.
Published: January 2005

The absorption spectra of cyclopropane, ethylene oxide, ethylene sulfide, and ethylene imine have been investigated in the region between 7000 and 12,000A and the stronger bands have been assigned as third harmonics of the fundamental C–H stretching frequencies of these molecules. Rotational fine structure was not observed under high dispersion, but the well-defined band envelopes of the three asymmetric rotators provide interesting examples of these little investigated band types.
The Spectrum of Allene in the Photographic Infra-Red
Authors: Eyster Eugene H.
Published: January 2005

The spectrum of allene between 7000 and 12,000A has been photographed under high dispersion, the observed bands being assigned as harmonics and combinations of fundamental frequencies of the molecule. Rotational analysis of the parallel band at 11,444A has given 97.0×10—40 g cm2 as the large moment of inertia. The perpendicular band at 11,017A has been found to be unexpectedly complicated, but was too weak for detailed analysis. It has been concluded that the dimensions in ethylene and allene are: C−H=1.087A,  C=C=1.330A,  H–C–H=116∘.
The Low Temperature Oxidation of Iron
Authors: Nelson H. R.
Published: January 2005

An electron diffraction study of the oxide films formed on abraded iron specimens by heating in air at temperatures ranging from 80° to 260°C has failed to detect structural effects due to a ``critical temperature'' in the neighborhood of 200°C. α-Fe2O3 was found on specimens which were oxidized at any temperature above about 130°C provided the period of oxidation exceeded a minimum value which depends upon the temperature. Thus 1 hour at 180°, 4 hr. at 165°, 13 hr. at 150° or 1000 hr. at 130° are just sufficient to produce an α-Fe2O3 film whose diffraction pattern is well defined. Lower oxidation temperatures or shorter times tend to strengthen the diffraction pattern due to the primary oxide film which is assumed to be γ-Fe2O3 (or Fe3O4) and is detectible immediately after the initial abrasive treatment. The strengthening of the primary oxide pattern is not accompanied by appreciable grain growth, however, and traces of iron are present in the pattern after oxidation periods as long as 1700 hr. at 120°C or below. Based on considerations of the presence of these iron rings it is estimated that the primary oxide film cannot be thicker than about 200A over some portions of the abraded surface. At 193°C and above the development of the first order blue interference color is characterized by the appearance of a new α-Fe2O3 film which is more coarsely crystalline and has a different type of preferred orientation than the first-formed α-Fe2O3 film. It is believed that this secondary film is formed by the outward diffusion of iron through the oxide layer. The axis of preferred orientation of the α-Fe2O3 is always symmetrical about the normal to the surface. This orientation cannot be attributed to pseudomorphism of the oxide crystals on the underlying iron as is the case with the primary oxide.
The Diffusion of Helium and of Hydrogen Through Pyrex Chemically Resistant Glass
Authors: Taylor Nelson W. , Rast William
Published: January 2005

The effects of temperature and of heat treatment on Pyrex chemically resistant glass have been studied by measuring the rate of diffusion of helium and of hydrogen through a tube of about one millimeter wall thickness. Measurements were made with helium between 180°C and 590°C, and with hydrogen at 512°C. The influence of gas pressure was determined and the diffusion rate was found to be directly proportional to the pressure for both helium and hydrogen.

The diffusion data throw light on the processes of molecular rearrangement involved in stabilization of the glass. Below 548°C the rates of diffusion (R) were increased about 10 percent by giving the glass sufficient heat treatment to assure ``stabilization,'' i.e., equilibrium in the processes of dissociation and association. This increase occurred despite the fact that such heat treatment normally increases the density of the glass and therefore points to a chemical theory rather than a simple theory of holes governing the diffusion process.

The data also showed a continuous linear dependence for the stabilized glass of log R on 1/T from 440°C—590°C. This range extends into the region of a true viscous liquid and it follows that the properties of a stabilized glass are continuous with that of a viscous liquid and that there is no need to postulate a separate glassy state. The ``transformation point'' mentioned by some investigators is merely the temperature of rapid strain release of an unannealed sample.

At or near 440°C the log R versus 1/T curve takes a lesser slope (for lower temperatures) and this change is attributed to the loss of rotational or vibrational freedom in the silicate complex, analogous to that frequently found in dielectric studies on solids. Activation energies have been calculated for the two temperature ranges.

At 512°C the rate of helium diffusion is approximately 45 times that of hydrogen, and it is believed that chemical forces delay the progress of the hydrogen molecule through the silicate network.

The general conclusion is drawn that gas diffusion furnishes a highly sensitive method for studying the molecular condition of silicate glasses and similar materials.
Order Versus Disorder in Ternary Structures Including Certain Spinels
Authors: Blake F. C.
Published: January 2005

The doubling process as the second alternative suggested by Professor M. v. Laue for mixcrystals is followed through in the case of lithium ferrite and it is shown in that case that all superlattice lines disappear when the lattice edge is eight times as large as the small disordered lattice found by Posnjak and Barth. It is shown that for this large (33A) lattice the simple space group, O1h, gives only face-centered lines on the powder photograph. The disappearance of the superlattice lines for this lattice may be said to be due to the coherence of the x-rays that cause the destructive interference involved.
X-Ray Analysis of the Structure of Water
Authors: Morgan J. , Warren B. E.
Published: January 2005

X-ray diffraction patterns of water were obtained at five temperatures: 1.5°, 13°, 30°, 62°, and 83°C. The radiation was Cu Kα and Mo Kα, monochromated by reflection from a rocksalt crystal. Radial distribution curves for water at the five temperatures were obtained by a Fourier analysis of the x-ray intensity curves. The first peak is only partially resolved, and it is not possible to interpret the distribution curves uniquely in terms of a definite number of neighbors at definite distances. The results can be interpreted in terms of a structure in which the tendency of a water molecule to bond itself tetrahedrally to 4 neighboring molecules is only partially satisfied.
Infra-Red and Raman Spectra of Polyatomic Molecules. III. Ethane
Authors: Crawford Bryce L. , Avery William H. , Linnett J. W.
Published: January 2005

The Raman and infra-red spectra of ethane have been re-examined. The 993, 2900, and 2955 cm—1 Raman lines are polarized; there were indications of very faint lines appearing at 620 and 820 cm—1. The strong infra-red peak at 1480 cm—1 is found to be a single minimum; the weak band at 1740 cm—1 is confirmed.

The available Raman and infra-red data are evaluated, and possible assignments discussed. It is shown that the observed frequencies do not require a 740 cm—1 fundamental, but are consistent with an ``uncertain frequency'' of about 1100 cm—1 and a high restricting potential.
The Band Envelopes of Unsymmetrical Rotator Molecules. I. Calculation of the Theoretical Envelopes
Authors: Badger Richard M. , Zumwalt Lloyd R.
Published: January 2005

Since the majority of molecules of chemical interest are too heavy to permit resolution of the rotational structure of the infra-red bands, it is of interest to find what information can be derived from a study of the band envelopes. Considerations of the type which Gerhard and Dennison have made for symmetrical molecules have been extended to the unsymmetrical rotator. By the use of an approximation method the envelopes of the three elementary types of band have been calculated for nine different sets of molecular parameters.
Modifications in the Near Infra-Red Absorption Spectra of Protein and of Light and Heavy Water Molecules When Water is Bound to Gelatin
Authors: Ellis Joseph W. , Bath Jean
Published: January 2005

Comparisons are made between the near infra-red absorption spectra of protein molecules in oven-dried gelatin and gelatin saturated with light and heavy water vapor respectively. The intensity of the first overtone valence N – H band at 1.50μ is greatly diminished by the addition of H2O molecules, and this band is almost completely destroyed when D2O molecules are taken on. The combination deformation-valence N – H bands at 2.05μ and 2.18μ are only partially destroyed in either instance. These facts suggest that the dipole moment oscillation of the N – H group constituting a part of the inter-molecular hydrogen bridge, C = O≡H – N, is reduced when this bridge is broken and water molecules themselves become bridged to the N – H group; that the transverse dipole moment change is less affected than the parallel change; and that D2O is much more effective than H2O.

The 1.72μ and 2.28μ C – H bands do not change appreciably in intensity. However, at least the former shifts toward higher frequencies when water is taken on, indicating that the C – H groups are in a more vapor-like environment and corroborating the usual assumption that water molecules are attached only to the polar groups of the gelatin molecules.

The destruction of some of the usual absorption on the short and the long wave sides of the 1.44μ (νσ+νπ) and 1.93μ (νσ+νδ)H2O bands indicates the nonexistence, or a reduction in number, of unperturbed vapor-like molecules as well as of the more highly perturbed molecules involving three and four hydrogen bridges. The presence of a sharpened and enhanced 1.79μ (νσ+νδ+νR) band indicates hindered rotation of H2O molecules in a field more homogeneous than that in liquid water but having the same average value. A new weak band appears at 1.35μ and is believed to be (νσ+νπ+νR). Somewhat similar results occur with D2O, requiring for complete interpretation, however, frequency contributions from hindered translation νT.
The Ultraviolet Absorption Bands Ascribed to HNO2
Authors: Newitt D. M. , Outridge L. E.
Published: January 2005

Attention is drawn to the similarity of a series of absorption bands obtained by Melvin and Wulf as the results of experiments at normal temperatures with a NO–NO2–H2O medium and by Bone and Newitt from the explosion of a CO–H2O–NO medium at high pressures. The formation of these bands in explosion experiments at atmospheric pressure and in static flames is described and evidence is brought forward which suggests that they may be due to the enhancement of certain bands of the normal NO2 absorption spectrum.
The Infra-Red Absorption of Carboxylic Acids in Solution II. Intensities
Authors: Davies M. M. , Sutherland G. B. B. M.
Published: January 2005

The integral absorption of the monomeric OH band has been measured for solutions of acetic, benzoic and lauric acids in CCl4 at various concentrations and temperatures. At any given temperature the results indicate that the integrated intensity is roughly proportional to the amount of the monomer present, assuming that there is a monomer⇌dimer equilibrium. The temperature variation of the integrated absorption gave values for the heat of association varying from 6000 to 10,000 cal./g mole, which is considerably below the accepted value of 15,000 cal./g mole. This difference is attributed to the variation in the absorption coefficient with temperature. Equally anomalous results were obtained from measurements on the intensity of the monomeric C=O band. The variation of the absorption coefficient with concentration and with temperature was checked independently on solutions of cetyl alcohol in CCl4.
An Infra-Red Study of Omega-Hydroxyundecanoic Acid in Carbon Tetrachloride
Authors: Davies Mansel M.
Published: January 2005

An infra-red examination of a long chain omega-hydroxycarboxylic acid has provided evidence as to the inter- and intramolecular association of such molecules in solution: In particular, it is believed that the occurrence of a cyclic form of the monomeric molecules in solution has been proved.
The Alpha-Particle Reactions in Carbon Monoxide, Oxygen and Carbon Dioxide Systems
Authors: Hirschfelder Joseph O. , Taylor Hugh S.
Published: January 2005

The methods developed by Eyring, Hirschfelder and Taylor for the analysis of the alpha-particle reactions in hydrogen and hydrogen-bromine systems have been extended to the corresponding reactions in carbon monoxide, oxygen, and carbon-dioxide systems and to mixtures of these gases. It has been shown that experimentally known processes of ionization and of excitation, together with the probable neutralization processes, with consequent chemical reactions involving the atomic species so produced, suffice to account quantitatively for the observed experimental results. This extends the scope of the method employed to typical alpha-particle reactions of decomposition, ozonization and oxidation hitherto interpreted in terms of a clustering mechanism.
Slow Electron Scattering and the Apparent Electron Affinity of Mercury
Authors: Simons J. H. , Seward R. P.
Published: January 2005

The scattering of slow electrons by gaseous molecules is discussed with the object of explaining the curves obtained when the apparent scattering area is plotted against a function of the electron velocity. The peaks frequently observed at about the ionization potential for most substances and the abnormally high values for the alkali metals are explained as being due to the formation or presence of positive ions. The rise in the curves for some substances, as the accelerating potential is diminished below the ionization potential, is explained as the result of an attractive force between the electron and the neutral molecule. It is shown that this attractive force for mercury approximates an inverse fourth-power law. From this law and an assumption of the diameter of the negative mercury ion, a reasonable value for the apparent electron affinity of mercury is calculated.
Integrals Required for Computing the Energy of H3 and of H3+
Authors: Hirschfelder Joseph O. , Weygandt Cornelius N.
Published: January 2005

Some of the difficult integrals required for the variational method calculation of the energy of the triatomic hydrogen molecule and positive ion were evaluated with the aid of the differential analyzer. The integral ∫ 0πexp (−B(1−A cos θ)12)dθ is tabulated for a complete range of the parameters, A and B. The integral K(c,ab)=(1/π) ∫ rc−1exp(−ra−rb)dτ is tabulated for many configurations of the three electrons or nuclei: a, b, and c. Numerical tables are given of all of the integrals occurring in the Sugiura treatment of the ground state of H2. The values of all of the other integrals used in the calculation of the energy of H3 and of H3+ are given. It is expected that these tables will be useful for many problems of molecular quantum mechanics.
The Reaction of Hydrogen Atoms with Carbon Tetrachloride
Authors: Vance John E. , Bauman W. C.
Published: January 2005

Reaction rate constants have been obtained at seven temperatures between 21° and 200° for the reaction H+CCl4=HCl+CCl3. The change of reaction rate with temperature is satisfactorily represented by the classical bimolecular reaction theory with a steric factor of 0.007 and an activation energy of 3.45 kcal. per mole. A comparison of the amount of HCl formed with the number of hydrogen atoms entering indicates that complete conversion of atomic hydrogen into HCl by the reaction may be attained at 150–200° under conditions which are determined in the experiments.
The Optical Activity of Secondary Butyl Alcohol
Authors: Gorin Everett , Walter John , Eyring Henry
Published: January 2005

A calculation of the optical activity of secondary butyl alcohol is presented based upon a one-electron model. The chromophoric electron is considered to be one of the nonbonding electrons on the oxygen atom. This electron is considered to be moving in a field of the other nuclei and electrons considered as charge distributions. The fields of the other electrons are obtained from the Slater type eigenfunctions for the various atoms. This amounts to a rough solution of the Hartree approximation for the chromophoric electron. The results obtained are somewhat larger or somewhat smaller than the experimental value depending on the exact orientation of the groups in their rotation about single bonds. The assignment of an absolute configuration in these calculations follows provided the exact orientation of the rotating groups is known. The orientations which we consider most likely lead to an assignment of the absolute configuration in agreement with that of Kuhn.
An Equation for Transference Numbers
Authors: Shedlovsky Theodore
Published: January 2005

The following transference number equation is proposed, 1/t=1/t0+AC12−BC.The values for the constant A are in accord with the Onsager theory for most uni-univalent electrolytes in water, but not for abnormal salts, such as silver nitrate, or for higher valence salts. However, the transference equation appears to have quite general applicability.
Molecular Interaction in Mixed Monolayers on Aqueous Subsolutions I. Mixtures of Alcohols, Acids and Amines
Authors: Harkins William D. , Florence Robert T.
Published: January 2005

Mixed films are of fundamental importance in biological systems, so mixtures of long chain alcohols, acids, and amines on acidic and basic subsolutions have been investigated. The principal effect of mixing is to change the conditions with respect to the pressure, area, and temperature at which one surface phase changes into another.

In general a mixture of two liquid films gives a monolayer of the same type, with the mean molecular area: a liquid expanded film is made more condensed by admixture of a substance which gives a condensed film, and the condensing action increases with the length of the hydrocarbon chain; an alcohol condenses an acid more than the corresponding acid. The interaction, or departure from the mean value may be either positive or negative, and on acid subsolutions is greatest when one of the components is an amine. Only in amine-acid mixtures is there an indication of chemical action. The 1 : 1 mixture of stearyl alcohol and stearic acid ``freezes'' at a much larger area than the film given by either component, so the area of the solid mixed film is abnormally high. The area interaction with an amine present is negative, and the potential interaction has a high value and is positive. Calcium ions in a basic subsolution condense a Type II to a solid Type I monolayer.
Migration and Photochemical Action of Excitation Energy in Crystals
Authors: Franck James , Teller Edward
Published: January 2005

A crystal which has absorbed a light quantum can be treated either as an assembly of molecules or else as a giant molecule. If the exchange of excitation energy between crystal cells is slow as compared to the periods of vibration, the first description is preferable; if it is fast, the second picture is better. Both cases are discussed in connection with the following question: To what extent can excitation energy absorbed by an arbitrary cell of the crystal be used photochemically at a specific point which may be far removed from the absorbing cell? The results are applied to the behavior of polymerized pseudoisocyanines, to the hypothetical photosynthetic unit and to the theory of sensitized photographic plates.
Infrared Absorption Studies IV. The Infrared Spectrum of Water in an Inert Solvent
Authors: Borst L. B. , Buswell A. M. , Rodebush W. H.
Published: January 2005

The infrared absorption spectrum of H2O, HDO and D2O in dilute solution in carbon tetrachloride and carbon bisulfide has been investigated with a grating of high resolving power, in the region 2.6–3.8μ. Several bands have been identified as v3 bands and the hitherto unobserved v1 band for H2O is believed to have been found. The frequencies observed are compared with the same frequencies in the vapor and a displacement of frequency which is proportional to the frequency itself is observed in solution. A fine structure is observed in the case of H2O which may be ascribed to rotation unless some other explanation is found. The spectrum in carbon bisulfide appears to be identical with that in carbon tetrachloride.
The Heat Capacity of Diamond from 70 to 300°K
Authors: Pitzer Kenneth S.
Published: January 2005

The specific heat of diamond has been measured over the temperature range 70 to 300°K, and is compared with the theoretical formula of Debye. Small but definite deviations are observed, which in both direction and order of magnitude are those to be expected when the approximations of the Debye formula are taken into consideration. The entropy of diamond at 298.1°K is 0.585±0.005 cal. per degree per mole.
On the Adiabatic Demagnetization of Caesium Titanium Alum
Authors: Van Vleck J. H.
Published: January 2005

Titanium salts should behave more simply than most materials under magnetic cooling, since the ground level of the paramagnetic ion is here inherently doubly degenerate and so unaffected by crystalline fields. De Haas and Wiersma show that as long as the magnetic moment remains constant during adiabatic demagnetization, the temperature is a linear function of a field strength, a most valuable fact since it permits the establishment of a thermodynamic temperature scale. The present paper computes when deviation of the moment from constancy should commence because of the perturbing effect of second-order terms (the first nonvanishing order) in the dipole-dipole coupling energy. The calculated moment does not remain constant to as low field strengths as reported experimentally. The discrepancy cannot be ascribed to a counter-balancing effect of exchange coupling but may be due to the neglect of third and higher order dipole terms. Because of these large dipole perturbations, the status of the experimental temperature scale in titanium alum becomes rather uncertain. The present stage of the theory may be tested more accurately by using much lower initial fields than in the existing Leiden experiments.
Fourier Analysis of Liquid Methyl Alcohol
Authors: Harvey G. G.
Published: January 2005

X-ray diffraction curves for liquid methyl alcohol have been obtained at 25°C and —75°C with monochromatic Mo Kα radiation out to (sin θ)/λ = 1.2. At —75°C there is much greater detail in the diffraction curve than is observable at the higher temperature. Five diffraction rings are visible on the film. Fourier analyses of these intensity curves lead to radial atom distribution functions which are interpreted in terms of Zachariasen's picture of the molecular arrangement in liquid methyl alcohol. The results are distinctly favorable to Zachariasen's picture.
Theory of Order for the Copper Gold Alloy System
Authors: Shockley W.
Published: January 2005

The theory of order and disorder, in the form used by Bragg and Williams, is extended to arbitrary composition of the constituent elements. The work is based upon the nearest neighbor interaction assumption of Bethe and the connection between the Bethe and Bragg-Williams theory is shown. In order to extend the Bragg-Williams theory to compositions other than 25 and 50 atomic percent, new definitions of order are developed. The results are presented in terms of phase diagrams and curves showing energy vs. temperature, specific heat vs. temperature and state order vs. temperature. These results are of importance in giving a general picture of the order-disorder transformation for a wide composition range. They are not in detailed accord with experiment due to the rather idealized picture underlying the nearest neighbor assumption.
Solvent Action on Optical Rotatory Power. II. The Quadrupole Field of the CS2 Type Molecule
Authors: Cohen Karl , Beckmann Charles O.
Published: January 2005

The applications of the general expression for the vectorial solvent field in organic liquids are further extended by detailed consideration of quadrupole molecules of the types CS2. The results of the computation are found satisfying from a theoretical standpoint. The experimental control is undertaken with the aid of a previously developed theory of optical rotatory power in solution. The results are found to be in accord with the existing data.
Effect of Electric Fields on the Decomposition of Ammonia by Alpha-Rays
Authors: Smith Catherine , Essex Harry
Published: January 2005

The following values have been obtained for the ion yields in the alpha-ray decomposition of gaseous ammonia in the absence and presence of electric fields at 30°C and 100°C: 30∘Cno field1.37half−saturation1.17full saturation1.08100∘Cno field2.42half−saturation2.06full saturation2.01The results are interpreted upon the hypothesis that in a field sufficiently strong to produce half-saturation, the ions are neutralized upon the plates without decomposition. If this hypothesis is correct, of the ion yield 1.37 at 30°C, 0.40 is the ion yield due to recombination of ions and 0.97 the ion yield due to other mechanisms. Similarly of the ion yield 2.42 at 100°C, 0.72 is the ion yield due to recombination of ions and 1.70 the ion yield due to other mechanisms. Possible mechanisms of that part of the reaction consequent on ion recombination and of that part of the reaction independent of ion recombination are discussed.
Infra-Red and Raman Spectra of Polyatomic Molecules I. An Automatic Prism Spectrometer for the Infra-Red
Authors: Gershinowitz Harold , Wilson E. Bright
Published: January 2005

A spectrometer has been constructed which contains two prisms, one of NaCl, the other of KBr, each in a Wadsworth-Littrow mounting. The prisms may be interchanged in the optical train without opening the spectrometer housing or disturbing the calibration. The recording system includes a Barnes-Matossi type amplifier using a photronic cell. The recording is done stepwise, so that the zero of the amplifying system, the intensity of the source and the intensity of transmitted radiation are measured at each setting of the prism table, which is moved by a ratchet device.
Chemical Reactions of Organic Compounds with X-Ray Activated Water
Authors: Fricke Hugo , Hart Edwin J. , Smith Homer P.
Published: January 2005

Gas free solutions of carbon monoxide, alcohols, aldehydes, ketones and acids were irradiated in the concentration range 10 μM to 1 M, between pH=1 to 13 and the reactions studied principally by gas analysis and potentiometric acid analysis. One organic component systems and, to a more limited extent, two organic component systems were investigated. To obtain significant results, foreign organic matter must be strictly excluded from the low concentration solutions and the methods used to accomplish this are described. Organic impurities in the water can be detected by irradiating the water with x-rays and measuring the evolved hydrogen and carbon dioxide. The reactions cannot be briefly abstracted, but oxidation and condensation reactions with the evolvement of gaseous hydrogen are important in the effect of the rays. Carbon dioxide was produced from certain acids, particularly strongly from those having an oxygen containing group in the α-position. No liberation of carbon monoxide, hydrocarbons or oxygen was found. The effect of the rays on all the compounds studied depends on the hydrogen ion concentration, this factor affecting reaction rates as well as the nature of the reactions. The relation of reaction rate to pH can in some cases be represented by [P]=A(1+10−pH+α/1+10−pH+α).The rates of the reactions are in many cases independent of concentration, at high concentrations, but generally the rates decrease at low concentrations. The reason for this decrease may be the deactivation of the activated water, although this interpretation would, because of the form of the reaction product concentration curves, lead to the conclusion that the deactivation is approximately monomolecular (rather than bimolecular) during its initial stage. The same conclusion is indicated since the reaction rates are independent of x-ray intensity down to the lowest concentrations used. The x-ray reactions show some similarity to, but they are generally more complex than, the reactions produced by water activated with light inside the absorption band at 1900A. The irradiation of formic acid in the presence of oxygen at pH=3, results in a smaller decomposition of the formic acid than is produced in the absence of oxygen and a higher production of hydrogen peroxide than is obtained when oxygen is irradiated alone. This increased hydrogen peroxide production can be accounted for as resulting from the reaction of the oxygen with the nascent hydrogen liberated in the organic reaction.
Separation of Gaseous Isotopes by Diffusion
Authors: Sherr R.
Published: January 2005

The behavior of a set of mercury diffusion pumps has been investigated and the separation factors for a number of isotopic mixtures have been determined. Formulae have been derived which give the dependence of enrichment on the choice of reservoirs. In addition, Barwich's theory for the fractionation process has been extended to the case of finite reservoirs. The solution for this problem is a slowly converging series, but a qualitative picture of the dependence of equilibrium time on various factors is obtained. The separation factors which have been found for the Hertz diffusion pumps for bromine in CH3Br, carbon in CH4, oxygen in O2 and H2O, Ne, and A are 1.005, 1.107, 1.045, 1.073, 1.198, and 1.154 per unit, respectively. Twelve pumps of the Hertz design, and seventeen modified units were used. The modifications were made in an attempt to improve the original design, but the factors obtained for these units are smaller. Auxiliary experiments indicate that the performance of the new units is seriously impaired by the presence of back diffusion and that increased factors can be obtained by eliminating the latter effect.
The Inhibition of Homogeneous Organic Decompositions
Authors: Rice F. O. , Polly O. L.
Published: January 2005

A free radical mechanism is proposed to account for the inhibition of organic decompositions by nitric oxide, based on the assumption that the nitric oxide can both start and stop reaction chains in the substrate. Propylene inhibits organic decompositions and a free radical mechanism appears to account for this effect also. Ethyl nitrite completely inhibits the oxygen promoted chain in acetaldehyde at 300°C but has only a relatively small effect at 500°C.
Measurements of Low Vapor Pressures of Alkali Halides
Authors: Mayer Joseph E. , Wintner Irmgard Hölder
Published: January 2005

The vapor pressures over the crystalline salts have been measured in the neighborhood of 900°K by Knudsen's method for the chlorides and bromides of sodium, potassium and rubidium. Heats of vaporization have been calculated from the data.
Raman Spectra of Deutero-Ethylenes
Authors: de Hemptinne M. , Jungers J. , Delfosse J. M.
Published: January 2005

All the different ethylenes, have been prepared, their Raman spectra in the liquid state measured and classified. A comparison between experimental data and theoretical predictions permits an estimate of the order of magnitude of the anharmonicity.
Raman Spectrum of Benzene Under High Dispersion and the Isotope Effect
Authors: Rao B. Sundara Rama
Published: January 2005

The Raman spectrum of benzene has been photographed using a fine slit and a high dispersion glass Littrow spectrograph. The faint companion at 984 cm—1 is found to possess an intensity ratio of 6 : 100 when compared with the principal Raman line at 992 cm—1. The view that this satellite arises from a benzene molecule in which one of the carbon atoms is replaced by the heavier isotope of atomic weight 13 is supported by this result. The distribution of intensity in the 3048 and 3062 Raman lines has been determined and the contours of the lines are drawn separately. The peaks of these two lines are found to be in the ratio of 1 : 1.35. The relatively sharp nature of 3062 and the diffuseness of 3048 are correlated with the facts that the former is a well-polarized Raman line whereas the latter is a fully depolarized line.
The Decomposition of Mercury Dimethyl
Authors: Cunningham John P. , Taylor Hugh S.
Published: January 2005

The thermal and photochemical decompositions of mercury dimethyl have been studied in presence and absence of hydrogen. The thermal process occurs measurably above 290° in absence of hydrogen and is complex, yielding ethane, methane and carbonaceous products. In presence of hydrogen there is no carbonaceous deposit and methane is predominantly formed with consumption of hydrogen, which accelerates the decomposition. The influence of surface effects has been noted. The photo-decomposition has been studied from 50–300°C. In absence of hydrogen, ethane is practically exclusively formed up to 200°. In presence of hydrogen, methane is formed at all temperatures, in increasing amounts with increase of temperature. A mechanism based on photo-decomposition to free methyl radicals with association to yield ethane and reaction with hydrogen to yield methane has been quantitatively determined. For the activation energy CH3+H2=CH4+H a value of 9±2 kcal. has been deduced.
Compressibilities of the Alkali Metals
Authors: Bardeen J.
Published: January 2005

As a further test of the method of Wigner and Seitz (for the calculation of the energies of the monovalent metals), the pressure variation of the compressibilities of the alkali metals is determined and compared with recent experimental results of Bridgman which extend to pressures of the order of 45,000 kg/cm2. Fröhlich's approximate analytic expression for the dependence of the energies of the alkali metals on volume suggests the following semi-empirical form: W=a/v+b/v23−c/v12.If the parameters are determined from (1) the lattice constant, (2) the energy, and (3) the compressibility (all at zero pressure), the expression gives values for the relative change in volume with pressure in close agreement with Bridgman's results. The constants so determined agree fairly well with Fröhlich's theoretical values. Compressibilities of Li and Na, as obtained from the more exact and fundamental calculations of the energies given in the preceding paper, are compared with the experimental values. Theoretical values for Na are in good agreement with experiment, but the corresponding values for Li are about fifteen percent too high. It is suggested that the polymorphic transition in Cs, which occurs at a pressure of about 22,000 kg/cm2, is a transition from the normal body-centered to a face-centered form, resulting from the nonelectrostatic interaction energy of the ions, which favors close packing.