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Updated: Aug 30, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Temperature-driven phase transition of Ti2CN from first-principles calculations
Jin Zhang1, Huafeng Dong2, Xinfeng Li3
1College of Education for the Future, Beijing Normal University, Zhuhai 519087, China. zhangjin225@bnu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|August 30, 2022
Summary
First-principles evolutionary simulations predict body-centered tetragonal Ti2CN as the most stable phase at 0 K. This compound undergoes phase transitions at higher temperatures, influenced by electronic and quasi-harmonic effects.
Area of Science:
- Materials Science
- Computational Materials Science
- Solid State Physics
Background:
- Titanium carbonitrides (Ti2CN) are technologically relevant materials.
- Understanding their phase stability and thermodynamic properties is crucial for material design.
Purpose of the Study:
- To predict the stable Ti2CN compound using first-principles evolutionary simulations.
- To investigate the temperature-dependent phase stability and thermodynamic properties of Ti2CN.
Main Methods:
- First-principles evolutionary simulations.
- First-principles calculations combined with the quasi-harmonic approximation.
- Analysis of Gibbs free energy contributions (harmonic, electronic, quasi-harmonic).
Main Results:
- Body-centered tetragonal I41/amd-Ti2CN is predicted as the most stable phase at 0 K.
- Phase transitions are predicted at 1698 K (to P42/mmc) and 1872 K (to R3̄m).
- Electronic and quasi-harmonic contributions significantly influence the phase transition curves.
Conclusions:
- The study provides a comprehensive understanding of Ti2CN phase stability and thermodynamics.
- Calculated temperature-dependent lattice parameters align with experimental data.
- Thermodynamic quantities like volumetric expansion coefficient and isothermal bulk modulus were determined and analyzed.
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