Journal ArticleDOI
Measurement of the Polarizabilities and Field Evaporation Rates of Individual Tungsten Atoms
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In this article, the relative field evaporation rates of tungsten kink site atoms at (110) plane edges and the absolute field eva-cation rates of individual Tungsten adatoms on ( 110) planes have been measured covering nine orders of magnitude.Abstract:
The relative field evaporation rates of tungsten kink site atoms at (110) plane edges and the absolute field evaporation rates of individual tungsten adatoms on tungsten (110) planes have been measured covering nine orders of magnitude. From the experimental data, the effective polarizabilities of the tungsten kink site atoms and the adatoms are found to be 4.6 ± 0.6 and 6.8 ± 1.0 A3, respectively. A theoretical consideration is given to explain why the effective polarizability of metal surface atoms depends on the atom‐to‐surface mirror plane distance, and therefore the atomic sites. The calculation also reveals a first power field dependent energy level shift, which is dependent upon the atom‐to‐surface plane distance. It is further shown that the classical image potential no longer holds at a distance smaller than 1 A from the metal surface.read more
Citations
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Journal ArticleDOI
Field ion microscope studies of single-atom surface diffusion and cluster nucleation on metal surfaces
TL;DR: In this article, the authors review the experimental procedures used in FIM surface diffusion studies and discuss the results in relation to the atomistics of crystal and epitaxial growth processes.
Journal ArticleDOI
Field ion image formation
TL;DR: In this article, a review of recent progress in field ion image formation is presented, with emphasis on those topics requiring further investigation, such as field evaporation, field adsorption, and field ionization.
Journal ArticleDOI
The stability and structure of high miller index platinum crystal surfaces in vacuum and in the presence of adsorbed carbon and oxygen
D.W. Blakely,Gabor A. Somorjai +1 more
TL;DR: The surface structures of twenty-two high Miller index crystal faces of platinum were studied in ultrahigh vacuum (uhv) when clean and in the presence of a monolayer of chemisorbed oxygen or carbon by low-energy electron diffraction (LEED).
Journal ArticleDOI
Field ion microscopy, field ionization and field evaporation
Erwin W. Müller,Tien T. Tsong +1 more
Journal ArticleDOI
Surface self‐diffusion on an fcc crystal: An atomic view
Guy Ayrault,Gert Ehrlich +1 more
Abstract: Migration of individual atoms self‐adsorbed on different low‐index planes of a face‐centered cubic metal has been studied for the first time. Diffusion coefficients and activation energies for the motion of rhodium on perfect planes of the rhodium lattice, in the absence of high fields, have been derived from direct observation of atomic positions, using a field ion microscope. Correlation effects arising from interactions with other rhodium atoms are observed; these may be important even at interatomic distances greater than 7.5 A. All diffusion parameters have therefore been derived from experiments with only a single atom on a plane. On the close‐packed (111), motion is apparent even at cryogenic temperatures, with an activation energy Vm of only 3.6 kcal/mole. On the (311), (110), and (331) planes, atom movement is strictly one dimensional along close‐packed [110] rows, with Vm at 12.4, 13.9, and 14.8 kcal/mole, respectively. The highest barrier, 20.2 kcal/mole, is found on the (100). On all surfaces the pre‐exponential factor Do is normal. These results are at variance with previous measurements on similarly structured planes of tungsten; however, further observations of single atoms are needed to establish the exact role of surface structure.
References
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Book
Field Emission and Field Ionization
TL;DR: In this article, the theory of field emission and its application in adaption is discussed. But the application of field ionization to adsorption has not been discussed in detail.
Journal ArticleDOI
Atomic polarizabilities and shielding factors
TL;DR: In this article, a detailed discussion of the methods of calculating atomic polarizabilities and shielding factors and the relationships between them are demonstrated, and a more accurate procedure, the coupled Hartree-Fock approximation, is described.
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Field ion microscopy : principles and applications
Erwin W. Müller,Tien T. Tsong +1 more
Journal ArticleDOI
The Atom‐Probe Field Ion Microscope
TL;DR: The atom probe FIM as discussed by the authors is a combination probehole FIM and mass spectrometer having single particle sensitivity, which is used to identify the chemical nature of the individually imaged atoms.
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Theory of the Work Function. II. The Surface Double Layer
TL;DR: In this paper, an approximate self-consistent solution of the Fock equations gives the charge density at the surface of a monovalent metal, where the surface barrier is due primarily to exchange and polarization forces, and that ordinary electrostatic forces play a minor role.