resumo
Due to their versatile composition and customizable properties, A2BC Heusler alloys have found applications in magnetic refrigeration, magnetic shape memory effects, permanent magnets, and spintronic devices. The discovery of all-d-metal Heusler alloys with improved mechanical properties compared to those containing main group elements presents an opportunity to engineer Heusler alloys for energy-related applications. Using high-throughput density-functional theory calculations, we screened magnetic all-d-metal Heusler compounds and identified 686 (meta)stable compounds. Our detailed analysis revealed that the inverse Heusler structure is preferred when the electronegativity difference between the A and B/C atoms is small, contrary to conventional Heusler alloys. Additionally, our calculations of Pugh ratios and Cauchy pressures demonstrated that ductile and metallic bonding are widespread in all-d-metal Heuslers, supporting their enhanced mechanical behavior. We identified 49 compounds with a double-well energy surface based on Bain path calculations and magnetic ground states, indicating their potential as candidates for magnetocaloric and shape memory applications. Furthermore, by calculating the free energies, we propose that 11 compounds exhibit structural phase transitions and suggest isostructural substitutions to enhance the magnetocaloric effect.
palavras-chave
TOTAL-ENERGY CALCULATIONS; PLANE-WAVE; MARTENSITIC-TRANSFORMATION; NI; CO; TRANSITION
categoria
Chemistry; Materials Science
autores
Fortunato, NM; Li, XQ; Schonecker, S; Xie, RW; Taubel, A; Scheibel, F; Opahle, I; Gutfleisch, O; Zhang, HB
nossos autores
Nuno Fortunato
Bolseiro de investigaçãoagradecimentos
We acknowledge the financial support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant no. 743116 - project" Cool Innov") and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Project-ID 405553726 - TRR 270. Lichtenberg high performance computer of the TU Darmstadt where calculations were performed for this project is gratefully acknowledged for the computational resources.