First-Principles Insights into Eu(ZnX)₂ (X = P, As) Zintl Compounds: Promising Spintronic, Thermoelectric, and UV-Optoelectronic Materials

Oral-In-person  · Withdrawn

Abstract

This study presents a comprehensive first-principles analysis of the structural, electronic, optical, thermoelectric, and elastic properties of Eu-based Zintl compounds Eu(ZnX)₂ (X = P, As) using the FP-LAPW method within the WIEN2k framework. Both compounds crystallize in the tetragonal ThCr₂Si₂-type structure (P-3m1 space group), with negative formation energies confirming their thermodynamic stability. Band structure calculations using the modified Becke–Johnson potential reveal metallic behavior in both spin channels, with significant contributions from localized Eu-4f states at the Fermi level—indicative of spin-polarized conduction and intrinsic ferromagnetism. Optical analyses show strong anisotropic absorption in the UV range, with prominent interband peaks at 5.8 eV for Eu(ZnP)₂ and 5.5 eV for Eu(ZnAs)₂, supporting their use in ultraviolet optoelectronics. Thermoelectric calculations reveal that Eu(ZnP)₂ achieves a Seebeck coefficient of –75 μV/K and a power factor exceeding 30 × 10¹⁰ μW·cm⁻¹·K⁻² at 850 K in the spin-down channel, highlighting its spin-caloritronic potential. Mechanically, Eu(ZnP)₂ is more ductile (G/B = 0.61), while Eu(ZnAs)₂ is harder and brittle (G/B = 0.96), with both compounds exhibiting high thermal stability. These results position Eu(ZnX)₂ as promising candidates for multifunctional devices in spintronics, thermoelectrics, and UV-optoelectronics.

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Presenters

  • Nasir Rahman

    • University of Lakki Marwat

Authors

  • Nasir Rahman

    • University of Lakki Marwat