X-ray photoelectron diffraction study of the approximant Al5Co2(001) quasicrystal
Lhonidas de Senna Junior1, Alexandre Pancotti2, Alex Sandre Kilian2
1Departamento de Física, Universidade Federal do Paraná-Curitiba, Brazil. gjpabreu@ufpr.br.
Physical Chemistry Chemical Physics : PCCP
|January 12, 2023
Summary
Researchers studied the intermetallic Al5Co2, a complex material. Surface analysis revealed an Al-rich termination, confirming its quasicrystalline approximant nature.
Area of Science:
- Materials Science
- Solid State Physics
- Crystallography
Background:
- The intermetallic Al5Co2 is recognized as a structurally complex material.
- It is classified as a low-order quasicrystalline approximant, necessitating detailed surface studies.
Purpose of the Study:
- To synthesize a single crystal of Al5Co2(001) using the Czochralski method.
- To characterize the surface structure and composition of Al5Co2(001).
- To determine the most probable surface termination model.
Main Methods:
- Single crystal growth via the Czochralski method.
- Surface characterization using X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), and X-ray photoelectron diffraction (PED).
- Crystal structure analysis using the MSCD software and LEED pattern interpretation.
Main Results:
- XPS analysis confirmed the surface composition consists solely of Al and Co.
- LEED patterns indicated a (1 × 1) surface termination, consistent with existing literature.
- Structural analysis and testing of four termination models identified an Al-rich surface layer as the most reliable termination.
Conclusions:
- The (1 × 1) termination of Al5Co2(001) was confirmed.
- The study successfully identified an Al-rich surface layer as the most stable termination.
- This research contributes to understanding the surface properties of quasicrystalline approximants.
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