Spin–orbit coupling driven electronic phase transition and multifunctional response in lead-free K₂WCl₆ double perovskite for spintronic and energy applications

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Abdelgaber M., Elkenany E. B., Bouferrache K., Ghebouli M., Fatmi M., YAYLACI M., ...Daha Fazla

Scientific Reports, cilt.16, sa.1, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 16 Sayı: 1
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1038/s41598-026-70096-2
  • Dergi Adı: Scientific Reports
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, EMBASE, MEDLINE, Directory of Open Access Journals, Zoological Record, Academic Search Ultimate (EBSCO), Natural Science Collection (ProQuest), Biological Science Database (ProQuest), Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest)
  • Anahtar Kelimeler: GGA + U, Half-metal, K₂WCl₆, Magnetic properties, Optical properties, Phonon, Spin-orbit coupling, Spintronics, Thermoelectric
  • Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
  • Recep Tayyip Erdoğan Üniversitesi Adresli: Evet

Özet

A comprehensive first-principles study reveals a spin–orbit coupling (SOC)-driven electronic phase transition in the lead-free double perovskite K₂WCl₆. The material exhibits a robust non-relativistic half-metallic ferromagnetic state. The inclusion of SOC strongly reconstructs the electronic states near the Fermi level: GGA + U+SOC predicts a magnetic-semiconducting state with a global band gap of approximately 1.572 eV, whereas TB-mBJ + SOC yields a metallic state. This method-dependent relativistic response reflects a close competition among exchange splitting, on-site electronic correlation, and SOC in the W-5d manifold. This transition arises from strong relativistic effects associated with W 5d orbitals, enabling tunable electronic behavior relevant for spintronic applications. In addition to its electronic versatility, K₂WCl₆ demonstrates excellent mechanical and dynamical stability. The compound also exhibits significant spin-dependent optical and thermoelectric responses, including high ultraviolet absorption, spin-dependent dielectric behavior, and notable spin-resolved Seebeck coefficients. The estimated thermoelectric figure of merit increases with temperature and can be substantially enhanced through chemical-potential optimization, although the reported values remain dependent on the constant-relaxation-time and Slack-model approximations. These combined features highlight K₂WCl₆ as a promising multifunctional material for spin-dependent thermoelectric, spintronic, and optoelectronic applications, while experimental validation and more advanced many-body and scattering calculations remain necessary.