Relativistic effects and pressure-induced phase transition in CsAu
Júlia F B Manfro1, Giovani L Rech1, Janete E Zorzi1
1Universidade de Caxias do Sul, 95070-560, Caxias do Sul, RS, Brazil. juliaflachm@gmail.com.
Physical Chemistry Chemical Physics : PCCP
|January 29, 2024
Summary
Relativistic effects significantly alter cesium auride (CsAu) properties, stabilizing its structure and influencing its transition to a conducting state under pressure. Simulations reveal key structural and electronic changes crucial for understanding CsAu
Area of Science:
- Computational Materials Science
- Solid-State Physics
- Quantum Chemistry
Background:
- Cesium auride (CsAu) exhibits unusual ionic salt properties despite being composed of two metals.
- Understanding the influence of relativistic effects is crucial for accurately modeling CsAu's behavior.
Purpose of the Study:
- To investigate the impact of relativistic effects on CsAu's structure and physical properties.
- To explore pressure-induced phase transitions and the transition to a conducting state in CsAu.
- To analyze the effect of high pressures on CsAu's electronic band gap.
Main Methods:
- Utilized computer simulations to model CsAu.
- Performed calculations with and without relativistic effects for comparison.
- Analyzed structural, volumetric, and electronic properties under varying pressures.
Main Results:
- Relativistic effects reduce CsAu's lattice parameter and enhance charge transfer, aligning volumetric properties with alkali halides.
- The electronic band gap of CsAu is predicted to close around 31.5 GPa.
- Relativistic effects stabilize the CsAu Pm3̄m structure and shift the transition to the P4/mmm phase to 14 GPa.
Conclusions:
- Relativistic effects are essential for accurate predictions of CsAu's properties and phase transitions.
- CsAu is expected to transition to a conducting state at high pressures.
- The P4/mmm phase may serve as an intermediate state towards a stable high-pressure CsAu phase.
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