Gold Polar Intermetallics: Structural Versatility through Exclusive Bonding Motifs

Area of Science:

• Materials Science
• Solid State Chemistry
• Crystallography

Background:

• Intermetallic phases are crucial for designing materials with specific properties.
• Polar intermetallics (PICs) bridge Hume-Rothery phases and Zintl compounds, with unclear formation mechanisms.
• PICs exhibit diverse crystal structures, incorporating features from nonpolar and Zintl compounds.

Purpose of the Study:

• To discover and synthesize new polar intermetallic compounds.
• To characterize their structures and investigate their properties.
• To analyze the principles governing their formation and systematize existing knowledge.

Main Methods:

• Focus on ternary intermetallic compounds of gold with metals from groups 12-15.
• Analysis of relativistic effects on chemical bonding and structural motifs.
• Systematic study of structure types, including common and novel formations.

Main Results:

• Gold, with high electronegativity, often acts as an anion in PICs.
• Relativistic effects in gold intermetallics lead to unique structural motifs.
• Observed structures range from common types (e.g., AlB2) to complex networks and clusters.

Conclusions:

• Polar intermetallics, especially those involving gold, offer a rich area for materials discovery.
• Understanding structure-property relationships in PICs is key to designing advanced materials.
• Systematization of PIC structures provides a foundation for future research.