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Updated: May 27, 2026
08:44
Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene
Published on: August 22, 2017
Correlation of electron self-energy with geometric structure in low-energy electron diffraction
J Vuorinen1, K Pussi, R D Diehl
1Department of Mathematics and Physics, Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta, Finland. johannes.vuorinen@tut.fi
Summary
Determining surface structures with low-energy electron diffraction (LEED) requires independent measurement of in-plane lattice parameters. Conventional LEED intensity (I-E) analysis cannot simultaneously determine these parameters and interlayer spacings due to inner potential correlation.
Area of Science:
- Surface Science
- Materials Science
- Condensed Matter Physics
Background:
- Low-energy electron diffraction (LEED) is crucial for analyzing surface geometries.
- Typically, LEED studies assume in-plane lattice parameters from bulk X-ray diffraction data.
- Determining surface structures for incommensurate films requires fitting in-plane parameters simultaneously with perpendicular spacings.
Purpose of the Study:
- To investigate the feasibility of simultaneously fitting in-plane lattice parameters and perpendicular interlayer spacings in LEED I(E) analysis.
- To identify limitations in conventional LEED analysis regarding complete surface structure determination.
- To propose alternative approaches for accurate surface structure determination.
Main Methods:
- Analysis of conventional LEED intensity (I-E) spectra.
- Investigating the correlation between inner potential and geometrical structure parameters.
- Evaluating the impact of inner potential energy dependence on LEED analysis.
Main Results:
- Conventional LEED I(E) analysis cannot simultaneously determine in-plane lattice parameters and perpendicular interlayer spacings.
- The inner potential is intrinsically correlated with the geometrical structure, preventing simultaneous fitting.
- Omitting the energy dependence of the real part of the inner potential limits geometrical accuracy to approximately 0.01 Å.
Conclusions:
- The in-plane lattice parameter must be determined independently before LEED I(E) analysis.
- Establishing a more precise experimental geometry is recommended for accurate parameter determination.
- Accurate surface structure determination using LEED requires careful consideration of inner potential effects and independent lattice parameter measurements.
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