Single crystal study of antiferromagnetic CePd3Al9

Area of Science:

• Condensed Matter Physics
• Materials Science
• Crystallography

Background:

• Cerium-based intermetallic compounds are crucial for understanding complex magnetic phenomena.
• Kondo lattice systems exhibit unique electronic and magnetic properties due to the interaction between localized f-electrons and conduction electrons.

Purpose of the Study:

• To synthesize and characterize a new tetragonal compound, CePd3Al9.
• To investigate the magnetic, thermodynamic, and transport properties of CePd3Al9.
• To determine the nature of the magnetic ordering and electronic behavior in this material.

Main Methods:

• Single crystal X-ray diffraction for structural determination.
• Magnetic susceptibility (M), heat capacity (C), and electrical resistivity (ρ) measurements.
• Analysis of Ce-Ce distances and electronic specific heat coefficient (γ).

Main Results:

• CePd3Al9 crystallizes in a new structure type with large Ce-Ce distances (5.272 Å).
• Antiferromagnetic order was observed near T(N) = 0.9 K.
• Evidence suggests a dilute Kondo lattice with weak Ce-conduction electron hybridization and significant structural disorder.

Conclusions:

• CePd3Al9 behaves as a stoichiometric dilute Kondo lattice with localized Ce ions.
• The magnetic ground state is influenced by weak hybridization and structural disorder.
• Magnetic field application leads to Zeeman splitting and a transition to a nonmagnetic singlet state.