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arXiv · 2512.09053

First-Principles Investigation of Mechanical, Lattice Dynamical, and Thermodynamic Properties of BaTiO3 Polymorphs

Arpon Chakraborty·M. N. H. Liton·M. S. I. Sarker·M. M. Rahman·M. K. R. Khan
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Abstract

BaTiO3 (BTO) is one of the most interesting classes of perovskite materials. The present study has been complied to explore some physical properties such as mechanical, vibrational, thermo-physical, and temperature dependent thermodynamic properties of BaTiO3 polymorphs comprehensively using first principles calculations based on density functional theory (DFT). All the polymorphs are found to be mechanically stable. The polymorphs are elastically anisotropic, machinable and have high hardness and toughness. The cubic phase possesses brittle nature while the other phases show ductile character. The high melting point of the polymorphs reveals that they can be used in tough situations. Also, three of the polymorphs can be used as thermal barrier coating. Moreover, we have also calculated the lattice dynamics and found improved results compared to the available results in the literature. In addition, the temperature and pressure dependent thermodynamic parameters of the polymorphs are evaluated and analyzed for the first time using the quasi-harmonic Debye model. The thermodynamic properties suggested that all phases would be good choices for application in the fields of automobiles, cooling systems, thermal electronic devices, thermal exchangers, and space crafts.

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Arpon Chakraborty, M. N. H. Liton, M. S. I. Sarker, M. M. Rahman, M. K. R. Khan. 2025-12-09. First-Principles Investigation of Mechanical, Lattice Dynamical, and Thermodynamic Properties of BaTiO3 Polymorphs. https://arxiv.org/abs/2512.09053

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