Branch points and the critical voltage effect in high-energy electron diffraction (Band theory models)

1977 ◽  
Vol 10 (20) ◽  
pp. 3941-3958 ◽  
Author(s):  
B F Buxton ◽  
J E Loveluck
Keyword(s):  
Electron Diffraction ◽  
High Energy ◽  
Energy Electron ◽  
Critical Voltage ◽  
Branch Points ◽  
High Energy Electron ◽  
Band Theory

scholarly journals A Summary of Low-angle X-ray Atomic Scattering Factors Measured by the Critical Voltage Effect in High Energy Electron Diffraction

1988 ◽  
Vol 41 (3) ◽  
pp. 461 ◽  
Author(s):  
AG Fox ◽  
RM Fisher
Keyword(s):  
Electron Diffraction ◽  
Form Factors ◽  
High Energy ◽  
Energy Electron ◽  
Free Atom ◽  
Critical Voltage ◽  
High Energy Electron ◽  
X Ray ◽  
Hexagonal Close Packed ◽  
Atomic Scattering

A summary of all the accurate (-0.1%) low-angle X-ray atomic scattering (form) factors for cubic and hexagonal close-packed elements which have been determined by the critical voltage technique in high energy electron diffraction (HEED) is presented. For low atomic number elements (Z ~ 40) the low-angle form factors can be significantly different to best free atom values, and so the best band structure calculated and/or X-ray measured form factors consistent with the critical voltage measurements are also indicated. At intermediate atomic numbers (Z:::: 40-50) only the very low-angle form factors appear to be different to the best free atom values, and even then only by small amounts. For heavy elements (Z ~ 70) the best free atom form factors appear to agree very closely with the critical voltage measured values and so, in this case, critical voltage measurements allow accurate determinations of Debye-Waller factors.

Kinematic Approximations in TED and RHEED Analysis of Reconstructed Surfaces

1990 ◽  
Vol 48 (2) ◽  
pp. 396-397
Author(s):  
L. -M. Peng ◽  
M. J. Whelan
Keyword(s):  
Electron Diffraction ◽  
Kinematic Analysis ◽  
Incident Beam ◽  
High Energy ◽  
Energy Electron ◽  
Great Success ◽  
High Energy Electron ◽  
Kinematic Approximation ◽  
Reconstructed Surfaces

In recent years there has been a trend in the structure determination of reconstructed surfaces to use high energy electron diffraction techniques, and to employ a kinematic approximation in analyzing the intensities of surface superlattice reflections. Experimentally this is motivated by the great success of the determination of the dimer adatom stacking fault (DAS) structure of the Si(111) 7 × 7 reconstructed surface.While in the case of transmission electron diffraction (TED) the validity of the kinematic approximation has been examined by using multislice calculations for Si and certain incident beam directions, far less has been done in the reflection high energy electron diffraction (RHEED) case. In this paper we aim to provide a thorough Bloch wave analysis of the various diffraction processes involved, and to set criteria on the validity for the kinematic analysis of the intensities of the surface superlattice reflections.The validity of the kinematic analysis, being common to both the TED and RHEED case, relies primarily on two underlying observations, namely (l)the surface superlattice scattering in the selvedge is kinematically dominating, and (2)the superlattice diffracted beams are uncoupled from the fundamental diffracted beams within the bulk.

Reflection high-energy electron diffraction based texture determination: Magnetic thin films for perpendicular media

2000 ◽  
Vol 87 (9) ◽  
pp. 5693-5695 ◽  
Author(s):  
Dmitri Litvinov ◽  
J. Kent Howard ◽  
Sakhrat Khizroev ◽  
Heng Gong ◽  
David Lambeth
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Magnetic Thin Films ◽  
High Energy ◽  
Energy Electron ◽  
High Energy Electron ◽  
Perpendicular Media
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