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AbstractAbstract
[en] We consider a simple model of the work function based on the overlapping spherical atomic charge-density approximation to the potential (the so-called Mattheiss construct). We show analytically that the dipole barrier of nonpolar crystals is simply related to a moment of the spherical densities, and hence there is no face dependence of the work function in this model. For the polar faces of polar crystals there is an additional face-dependent term that was found previously by different means. We calculate the bulk contributions to the work function for the metals with atomic number less than 50. The dipole barriers obtained from free-atomic densities result in work functions which are on the average approx.80% too large. The use of contracted atomic densities, while leaving the bulk density virtually unchanged, decreases the dipole barriers and yields work functions in reasonable agreement with experiment. Some implications for surface calculations, electronegativity scales, and charge-transfer and bonding trends are briefly discussed
Record Type
Journal Article
Journal
Physical Review. B, Condensed Matter; ISSN 0163-1829;
; v. 29(6); p. 3001-3008

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Arakawa, E.T.; Birkhoff, R.D.; Callcott, T.A.
Health Physics Division annual progress report for period ending July 31, 19721972
Health Physics Division annual progress report for period ending July 31, 19721972
AbstractAbstract
No abstract available
Source
Oak Ridge National Lab., Tenn. (USA); p. 13-18; Sep 1972
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Report
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AbstractAbstract
No abstract available
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Journal Article
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Progress Report
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Phys. Rev., B; v. 2 p. 1-2
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AbstractAbstract
[en] The main idea of the adsorbed xenon photoemission method for studying local work functions var-phi loc of an electron on a heterogeneous surface is based on the relation triangle EFb = -triangle var-phi loc, where triangle EFb is the difference between the binding energies of the Xe5p1/2 level relative to the Fermi level of the adsorbed Xe atom of different regions of a heterogeneous surface, and triangle var-phi loc is the difference between the local work functions at these regions
Source
Cover-to-cover Translation of Doklady Akademii Nauk SSSR Seriya Fizicheskoj Khimii; Translated from Doklady Akademii Nauk, Seriya Fizicheskoj Khimii; 342: No. 4, 769-771(1995).
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Journal Article
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Translation
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AbstractAbstract
[en] It has recently been observed that adsorbed Au and Hg do not quench the W(100) surface resonance up to monolayer coverage. We report here that Cu does quench the W(100) surface resonance at theta > = 0.5 monolayers. This suggests that the effective potential of Cu differs more strongly from that of W than do the effective potentials of Au or Hg. (orig.)
[de]
Vor kurzem wurde beobachtet, dass die W(100)-Oberflaechenresonanz von adsorbiertem Au und Hg bis zu monoatomarer Bedeckung nicht unterdrueckt wird. Diese Arbeit zeigt, dass adsorbiertes Cu die W(100)-Oberflaechenresonanz fuer Bedeckungen groesser als eine halbe monoatomare Schicht zum Verschwinden bringt. Deshalb zeigt vermutlich das effektive Potential des Cu einen groesseren Unterschied zum effektiven W-Potential als Au und Hg. (orig.)Source
4 figs.; 8 refs.
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Journal Article
Journal
Applied Physics; v. 13(3); p. 303-305
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AbstractAbstract
[en] Calculations of positron and positronium atom work functions in transition metals are described with an analysis of the surface and internal contributions. Negative work functions are obtained for elements towards the centre of the transition series, in qualitative agreement with experimental observations. (author)
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Journal Article
Journal
Solid State Communications; v. 18(8); p. 1115-1118
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Smith, D.H.; Duckworth, D.C.; Bostick, D.T.; Coleman, R.M.; McPherson, R.L.; McKown, H.S.
Proceedings of the 42nd ASMS conference on mass spectrometry and allied topics1994
Proceedings of the 42nd ASMS conference on mass spectrometry and allied topics1994
AbstractAbstract
[en] The goal of this investigation was to extend the ability to perform isotopic analysis of plutonium to samples as small as possible. Plutonium ionizes thermally with quite good efficiency (first ionization potential 5.7 eV). Sub-nanogram sized samples can be analyzed on a near-routine basis given the necessary instrumentation. Efforts in this laboratory have been directed at rhenium-carbon systems; solutions of carbon in rhenium provide surfaces with work functions higher than pure rhenium (5.8 vs. ∼ 5.4 eV). Using a single resin bead as a sample loading medium both concentrates the sample nearly to a point and, due to its interaction with rhenium, produces the desired composite surface. Earlier work in this area showed that a layer of rhenium powder slurried in solution containing carbon substantially enhanced precision of isotopic measurements for uranium. Isotopic fractionation was virtually eliminated, and ionization efficiencies 2-5 times better than previously measured were attained for both Pu and U (1.7 and 0.5%, respectively). The other side of this coin should be the ability to analyze smaller samples, which is the subject of this report
Secondary Subject
Source
Anon; 1233 p; 1994; p. 839a-839b; ASMS; East Lansing, MI (United States); 42. American Society of Mass Spectrometry (ASMS) conference on mass spectrometry and allied topics; Chicago, IL (United States); 29 May - 3 Jun 1994; ASMS, P.O. Box 1508, East Lansing, MI 48826-1508 (United States)
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Book
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Conference
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Pipes, P.B.; Darling, D.H.
Dartmouth Coll., Hanover, N.H. (USA). Dept. of Physics and Astronomy1975
Dartmouth Coll., Hanover, N.H. (USA). Dept. of Physics and Astronomy1975
AbstractAbstract
[en] For a superconductor in a stationary condition, it can be shown that a gradient in the chemical potential is balanced by a gradient in the internal electrostatic potential. An attempt has been made to measure these electrostatic effects directly for niobium by measuring the temperature derivative of the contact potential as a function of temperature. (1 figure)
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Secondary Subject
Source
1975; 4 p; Conference on decontamination and decommissioning of ERDA facilities; Idaho Falls, Idaho, USA; 19 Aug 1975; CONF-750827--3
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Report
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Conference
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AbstractAbstract
[en] Starting from a definition of the work function in terms of total energies of the electron system it is shown that this work function can be obtained from the single-particle Schroedinger equations in the density-functional formalism in the way suggested by the Sommerfeld model. It is also shown that the change of the equilibrium ion positions accompanying the ionization of the crystal has no influence on the work function. A comparison is made with Koopmanns' theorem. The use of several potentials for computations of the work function is critically investigated. (orig.)
[de]
Ausgehend von der Definition der Arbeitsfunktion durch die Gesamtenergie des Elektronensystems wird gezeigt, dass diese Arbeitsfunktion im Rahmen des Dichte-Funktional-Formalismus auf die im Sommerfeld'schen Modell vorgeschlagene Art und Weise aus den Einteilchen-Schroedingergleichungen abgeleitet werden kann. Ausserdem wird gezeigt, dass die Aenderung der Gleichgewichtslagen der Ionen, wie sie bei der Ionisation des Kristalls auftreten, keinen Einfluss auf die Arbeitsfunktion hat. Ein Vergleich mit dem Theorem von Koopman wird angestellt. Die Verwendung mehrerer Potentiale zur Berechnung der Arbeitsfunktion wird kritisch untersucht. (orig.)Source
22 refs.
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Journal Article
Journal
Z. Phys., B; v. 27(4); p. 303-307
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AbstractAbstract
[en] Analysis of equations enabling determination of local work function of electron on heterogeneous surface is presented. Concrete values of local work yield, its changes after Xe-adsorption are given for Ru(0001), W(110), etc. 15 refs., 1 tab
Original Title
Lokal'nye raboty vykhoda ehlektrona na geterogennoj poverkhnosti
Secondary Subject
Record Type
Journal Article
Journal
Doklady Akademii Nauk - Rossijskaya Akademiya Nauk; ISSN 0869-5652;
; CODEN DAKNEQ; v. 342(6); p. 769-771

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