Electron-Poor Polar Intermetallics: Complex Structures, Novel Clusters, and Intriguing Bonding with Pronounced...

Area of Science:

• Materials Science
• Solid State Chemistry
• Crystallography

Background:

• Intermetallic compounds offer diverse properties for energy applications.
• Valence electron-poor polar intermetallics exhibit complex structures challenging traditional bonding rules.
• Understanding structure-bonding-property relationships is crucial for discovering new materials.

Purpose of the Study:

• To explore novel valence electron-poor polar intermetallics.
• To investigate structure-bonding-property relationships in these compounds.
• To identify new structural motifs and bonding characteristics.

Main Methods:

• Exploratory synthesis of intermetallic compounds, focusing on compositions near quasicrystals.
• Investigated Au-rich phases (AAu3T), lithiated Zn-rich compounds, and rare earth-rich intermetallics.
• Analysis of structural stability, chemical bonding, and valence electron concentrations (VECs).

Main Results:

• Discovered unprecedented polar intermetallic phases with novel structural motifs (e.g., wavy layers, clathrate frameworks, lonsdaleite-type structures).
• Identified specific bonding features in Au-rich compounds influenced by relativistic effects.
• Observed complex clusters and delocalized multicenter bonding in rare earth-rich intermetallics.

Conclusions:

• Three distinct systems of valence electron-poor polar intermetallics yield novel phases.
• Valence electron tuning is key to discovering complex structures and understanding bonding.
• These findings contribute to fundamental chemical principles and potential material applications.