Structural Phase Transitions in PtIn2 at High Pressure: A Theoretical Investigation
1High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre , Trombay, Mumbai 400085, India.
Inorganic Chemistry
|November 17, 2017
Summary
Researchers explored platinum-indium (PtIn2) under high pressure, discovering new crystal structures and increased covalent bonding. These findings advance the design of novel intermetallic materials for various applications.
Area of Science:
- Materials Science
- Solid State Physics
- Computational Chemistry
Background:
- Understanding intermetallic properties under pressure is key for novel material development.
- Crystal structures dictate the bonding and electronic characteristics of materials.
Purpose of the Study:
- To investigate the high-pressure structural behavior of PtIn2.
- To elucidate the relationship between pressure, electronic properties, and structural transitions in PtIn2.
Main Methods:
- Utilized crystal structure search calculations combining evolutionary algorithms.
- Employed state-of-the-art density functional theory (DFT) for analysis.
Main Results:
- Proposed three new crystal structures for PtIn2 at high pressures: Fe2B-type (I4/mcm), cotunnite-type (Pnma), and monoclinic (C2/m).
- Observed an increase in covalent character of Pt-In interactions with increasing pressure.
- Linked structural transitions to the enhanced spd hybridization and increased covalency.
Conclusions:
- High pressure induces significant structural transformations in PtIn2.
- Covalency plays a critical role in the pressure-induced structural evolution of intermetallics.
- The findings provide insights for designing advanced intermetallic materials.
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