Structural, electronic, magnetic and thermoelectric properties of Tl2 NbX6 (X = Cl, Br) variant perovskites calculated via density functional theory

Malak Azmat Ali; Aboud Ahmed Awadh Bahajjaj; Samah Al-Qaisi; Mika Sillanpää; Afzal Khan; Xiaoyu Wang

doi:10.1002/jcc.27166

Structural, electronic, magnetic and thermoelectric properties of Tl₂ NbX₆ (X = Cl, Br) variant perovskites calculated via density functional theory

J Comput Chem. 2023 Sep 5;44(23):1875-1883. doi: 10.1002/jcc.27166. Epub 2023 May 24.

Authors

Malak Azmat Ali¹, Aboud Ahmed Awadh Bahajjaj², Samah Al-Qaisi³, Mika Sillanpää⁴, Afzal Khan⁵, Xiaoyu Wang⁶

Affiliations

¹ Department of Physics, Government Post Graduate Jahanzeb College Saidu Sharif, Swat, Pakistan.
² Chemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
³ Palestinian Ministry of Education and Higher Education, Nablus, Palestine.
⁴ Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark.
⁵ Department of Physics, University of Peshawar, Peshawar, Pakistan.
⁶ State Key Labortory of Superhard Materials, Key Labortory of Automobile Mateials of MOE, Jilin Provential Intenational Cooperation Key Labortory of High-Efficiency Clean Energy Materials, School of Materials Science and Engineering, Jilin University, Changchun, China.

PMID: 37224190
DOI: 10.1002/jcc.27166

Abstract

This article presents detailed structural, electronic, magnetic, and thermoelectric properties of two experimentally existing isostructural variant perovskite compounds Tl₂ NbX₆ (X = Cl, Br) with the help of first principles calculations. As per requirement of stability in the device applications, the structural and thermodynamic stabilities were, respectively verified by tolerance factor and negative formation energies. The structural parameters in ferromagnetic phase were calculated and found in close agreement with the available experimental results. The electronic nature was found as half metallic from spin polarized calculations of electronic band structures and density of states, where the semiconductor nature was found in the spin down states and metallic nature in the spin up states. The magnetic moments of both the compounds were calculated as 1 μ_B majorly contributed by Nb atom. The Boltzmann transport theory was implemented via BoltzTraP for calculating the spin resolved thermoelectric parameters, such as Seebeck coefficient, electronic and thermal conductivities, and figure of merit. Overall, both the compounds were found suitable for use in spintronics and spin Seebeck effect for energy applications.

Keywords: ferromagnetic; half metallic; spin Seebeck effect; spintronics; variant perovskites.