Synthesis and characterization of intermetallic compounds with one medium- or high-entropy sublattice occupied by p-block elements

Materials Chemistry and Physics. 2023. Vol. 301. Article 127596.

Trofimov E., Ostovari Moghaddam A., Zaitseva O., Fereidonnejad R., Naseri M., Shaburova N., Mikhailov D.

The use of p-block elements to form a high-entropy sublattice in the chemically complex intermetallic compounds (CCICs) is justified. The results suggest that the possibility of mutual compensation of the characteristics (i.e. electronegativity and atomic radius) should be considered when developing new criteria to predict the stability of CCICs. The unraveled Cu3(InSnSb), Cu3(InSnSbGa), Cu3(InSnSbGe), Cu3(InSnSbGeSi) and Cu3(InSnSbGaGe) CCICs with one medium- or high-entropy sublattice occupied by p-elements were synthesized for the first time. Cu3(InSnSb) crystallized into a orthorhombic Cu3Sn type structure (space group Pmmn), while samples with four or five elements occupying the high entropy sublattice site crystallized into a hexagonal Cu10Sn3 type structure (space group P63/m), except Cu3(InSnSbGeSi) that crystallized into a mixture of Cu3Sn and Cu15Si4 type structures. The change in the crystal structure upon adding Ge and Ga could be attributed to the intrinsic nature and partial deviation from the stoichiometric ratios of the elements occupying the low- and high-entropy sites.

Keywords: Crystal structure, Chemically complex intermetallic compounds, Stabilization criteria, p-elements