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Articles 1 - 13 of 13
Full-Text Articles in Physical Sciences and Mathematics
Comment On The Negative Ion States Of Fluorobenzenes, K.D. Jordan, Paul Burrow
Comment On The Negative Ion States Of Fluorobenzenes, K.D. Jordan, Paul Burrow
Paul Burrow Publications
It is contended that several assignments given by the model employed by Frazier et al1 should be reconsidered especially of the anion states aniline phenol and anisole. The symmetry assignments of the anion states of fluorobenzene and p difluorobenzend as given by this model are incorrect.
Magnetic Ordering And Exchange Interactions In The Rare-Earth Gallium Compounds R Ga2, T.-H. Tsai, David J. Sellmyer
Magnetic Ordering And Exchange Interactions In The Rare-Earth Gallium Compounds R Ga2, T.-H. Tsai, David J. Sellmyer
David Sellmyer Publications
Magnetic ordering and indirect exchange interactions were studied in the series of hexagonal rare-earth intermetallic compounds R Ga2, where R denotes Ce, Pr, Nd, Gd, Tb, Dy, Ho, and Er. The magnetic susceptibility (χ) of polycrystalline samples was measured at low fields, from 1.5 K to about 300 K; the magnetization (M) versus applied magnetic field (H) of these polycrystalline samples and a HoGa2 single crystal was measured up to 80 kOe at low temperatures; the resistivities (ρ) of CeGa2, GdGa2, DyGa2, and HoGa2 were measured …
Photoionization Of Chalcogen And Halogen Atoms: Cross Sections And Angular Distributions, Steven T. Manson, Alfred Msezane, Anthony F. Starace, Siamak Shahabi
Photoionization Of Chalcogen And Halogen Atoms: Cross Sections And Angular Distributions, Steven T. Manson, Alfred Msezane, Anthony F. Starace, Siamak Shahabi
Anthony F. Starace Publications
The authors present a survey of the photoionization cross sections and photoelectron angular distributions for the outer p subshell of the chalcogen atoms O, S, Se, and Te and the halogen atoms F, Cl, Br, and I. Results are presented in the Hartree-Fock approximation as well as in the central-potential-model approximation. An extensive analysis and comparison of the results obtained is presented which finds that exchange-interaction effects are strongest for the n=3 row elements.
Magnetically Dilute Metallic Glasses. Ii. 4F Moments, G.R. Gruzalski, David J. Sellmyer
Magnetically Dilute Metallic Glasses. Ii. 4F Moments, G.R. Gruzalski, David J. Sellmyer
David Sellmyer Publications
Magnetic-susceptibility and high-field magnetization measurements are presented for amorphous Zr40Cu600-xMx (M denoting Gd and Tb), with x ranging from zero to ten. Effective moments of magnetic solutes were determined by fitting susceptibility data to the Curie-Weiss expression. The moments of Gd and Tb are very close to those expected for trivalent ions and the paramagnetic Weiss temperatures are positive. Saturation did not occur in any of the samples, even at 80 kOe and 1.3 K; however, the alloys containing Gd approached normalized magnetization values of unity. High-field hysteresis loops were used to obtain the …
Magnetically Dilute Metallic Glasses. I. 3D Moments, G.R. Gruzalski, David J. Sellmyer
Magnetically Dilute Metallic Glasses. I. 3D Moments, G.R. Gruzalski, David J. Sellmyer
David Sellmyer Publications
Magnetic-susceptibility and high-field magnetization measurements are presented for amorphous Zr40Cu50M10 (M denoting Fe, Mn) and Nb50Ni50-xFex, with x ranging from zero to about ten. Curie-Weiss fits to the susceptibility data were made to determine effective moments peff and paramagnetic Weiss temperatures, ⊖. The small values of peff suggest the presence of moment instabilities depending on local environment, and the negative ⊖ values suggest antiferromagnetic local-moment-conduction-electron interactions. The Fe alloys develop hysteresis at low temperatures indicating the presence of a magnetically ordered state. These alloys can be …
Photometric Measurements Of Thin Tracks In Nuclear Emulsion, Robert Katz
Photometric Measurements Of Thin Tracks In Nuclear Emulsion, Robert Katz
Robert Katz Publications
Difficulties observed in the application of track theory to CNO particles are attributed to problems in the application of a light scattering correction in microphotometry.
Ab Initio Treatment Of Final-State Spin-Orbit Interactions: Photoionization Of The 6S Electron In Cesium, Keh-Ning Huang, Anthony F. Starace
Ab Initio Treatment Of Final-State Spin-Orbit Interactions: Photoionization Of The 6S Electron In Cesium, Keh-Ning Huang, Anthony F. Starace
Anthony F. Starace Publications
Ab initio theoretical calculations are presented for the cross section, photoelectron angular distribution, and photoelectron spin polarization resulting from photoionization of the 6s electron of cesium. Starting from an initial basis of nonrelativistic Hartree-Fock wave functions, the effect of final-state spin-orbit interaction in the Breit-Pauli approximation is treated exactly. The effect of core relaxation is also examined. Our calculated results agree with recent experimental measurements of the photoionization cross section and the photoelectron spin polarization. Comparison is made with other theoretical calculations. Finally, the length form of the electric dipole interaction operator is shown to be consistent with gauge invariance …
Magnetic Properties Of Iron-Doped Layer-Structure Dichalcogenides , S.J. Hillenius, R.V. Coleman, E.R. Domb, David J. Sellmyer
Magnetic Properties Of Iron-Doped Layer-Structure Dichalcogenides , S.J. Hillenius, R.V. Coleman, E.R. Domb, David J. Sellmyer
David Sellmyer Publications
Magnetic-susceptibility measurements have been made on dilute excess Fe alloys of the layer-structure crystals TaSe2, NbSe2, and TaS2. The 2H selenides show local-moment formation and obey a Curie-Weiss law in the range 300-30 K with effective moments in the range (2.5-4.5)μB. For 2H-FexTaSe2 a strong susceptibility maximum is observed at low temperature and at low fields the maximum has a cusplike shape characteristic of a "spin-glass" type transition. The temperature of the maximum scales approximately linearly with Fe concentration and reaches 13 K for x=0.10. …
Electronic Properties And Superconductivity Of Zr-Pd Glasses, G.R. Gruzalski, J.A. Gerber, David J. Sellmyer
Electronic Properties And Superconductivity Of Zr-Pd Glasses, G.R. Gruzalski, J.A. Gerber, David J. Sellmyer
David Sellmyer Publications
Electrical-resistivity measurements between 1.4 and 300 K and room-temperature magnetic-susceptibility measurements were performed on the metallic glasses ZrxPd1-x, for x=0.59, 0.63, 0.67, and 0.70. The samples, prepared by a modified hammer-anvil technique, exhibit negative temperature coefficients of the resistivity at temperatures from about 10 to 300 K. These data can be understood in terms of the extended Ziman theory if it is assumed that Zr and Pd contribute about 2 and 1 conduction electrons, respectively. Assuming that the magnetic susceptibility is a qualitative measure of the electronic density of states at the Fermi level, N …
Atomic Hydrogen In A Uniform Magnetic Field: Low-Lying Energy Levels For Fields Below 109 G, Anthony F. Starace, Gary L. Webster
Atomic Hydrogen In A Uniform Magnetic Field: Low-Lying Energy Levels For Fields Below 109 G, Anthony F. Starace, Gary L. Webster
Anthony F. Starace Publications
The wave function for an electron in combined Coulomb and uniform magnetic fields is expanded in oblatespheroidal angle functions. The resulting Schrödinger equation for the radial function is solved for the energy levels by means of two different adiabatic approximations, which yield rigorous lower and upper bounds on the lowest exact energy levels for each symmetry state of the system. Results are presented for the level and binding energies of hydrogenic 1s, 2s, and 2p levels for magnetic fields in the range 107≤B≲1011 G and compared with results of other …
Temperature Dependence Of Alignment Production In He I By Beam-Foil Excitation, Timothy J. Gay, H. G. Berry
Temperature Dependence Of Alignment Production In He I By Beam-Foil Excitation, Timothy J. Gay, H. G. Berry
Timothy J. Gay Publications
We have measured the dependence upon target-foil temperature of the linear polarization fraction (M / I) of the 2s1S-3p1P, 5016-Å transition in He I for ion energies between 60 and 180 keV. The thin carbon exciter foils were heated externally by Nichrome resistance elements. The measurements of Hight et al. are duplicated; the energy and current dependencies of M / I are the same, assuming correspondence between beam heating and external heating. We also observe that γ, the number of secondary electrons produced per incident ion, decreases with increasing foil …
Magnetic Properties Of The Rare-Earth Glasses (R65Fe35)100-XBX, J.A. Gerber, S.G. Cornelison, W.L. Burmester, David J. Sellmyer
Magnetic Properties Of The Rare-Earth Glasses (R65Fe35)100-XBX, J.A. Gerber, S.G. Cornelison, W.L. Burmester, David J. Sellmyer
David Sellmyer Publications
Results are reported on the magnetic properties of (R65Fe35)100-xBx glasses, where R denotes Y, Gd, and Er, and x is 10 or 20. Curie-Weiss fits were made to high temperature susceptibility data to determine average effective moments per magnetic ion and Weiss temperatures. Hysteresis loops and modified Arrott plots were used to determine the spontaneous magnetizations, coercive forces, and ordering temperatures. The effective moments and spontaneous moments are compared with those calculated on the assumption of local moments on both magnetic subnetworks, and assuming various spin structures. There is evidence for moment instabilities …
Energy And Angular Distributions Of Secondary Electrons From 5-100-Kev-Proton Collisions With Hydrogen And Nitrogen Molecules, M. Eugene Rudd
Energy And Angular Distributions Of Secondary Electrons From 5-100-Kev-Proton Collisions With Hydrogen And Nitrogen Molecules, M. Eugene Rudd
M. Eugene Rudd Publications
Cross sections for the ejection of electrons from hydrogen and nitrogen by protons have been measured as a function of the energy and angle of ejection of the electrons at incident proton energies of 5-70 keV and 100 keV for hydrogen. The range of angles measured was 10-160° and the electron energy range was 1.5-300 eV. The doubly differential cross sections were also integrated over angle, over electron energy, or over both to obtain singly differential and total cross sections for electron production. Average electron energies were also calculated from the data. The angular distributions of electrons are peaked in …