Crystal structure of AlFe_0.95.

Area of Science:

• Materials Science
• Solid State Chemistry
• Crystallography

Background:

• The aluminum-iron (Al-Fe) binary system exhibits complex intermetallic phases.
• Understanding the precise crystal structure and defect chemistry of these phases is crucial for materials development.

Purpose of the Study:

• To synthesize and characterize B2-type Al-Fe intermetallic phases.
• To determine the exact crystal structure and identify vacancy defects in the AlFe$_{1 - δ}$ phase with δ = 0.05.

Main Methods:

• Smelting and high-temperature sintering for phase synthesis.
• Single-crystal X-ray diffraction for precise crystal structure determination.
• Refinement of site occupancy factors to quantify vacancy defects.

Main Results:

• Three B2-type Al-Fe intermetallic phases were successfully synthesized.
• The crystal structure of AlFe$_{1 - δ}$ (δ = 0.05) was refined, yielding the formula AlFe$_{0.95}$.
• Vacancy defects were quantified at the Fe atom sites, explaining the deviation from stoichiometry.

Conclusions:

• The synthesized AlFe$_{0.95}$ phase possesses a crystal structure consistent with ideal AlFe models.
• Vacancy defects at Fe sites are a key feature of this intermetallic phase.
• The findings provide precise structural data for Al-Fe intermetallics.