We found the proper correction for electron localization, which strongly improves the accuracy of ab initio calculations on Ni-Mn-Ga based magnetic shape memory alloys. With the correction, the calculations (DFT with GGA+U potential approximation) finally correspond closely to the key experimental material parameters, e.g. lattice constants. The method is the cornerstone for further material design and theoretical determination of twinning stress. This has corresponding benefit on our ability to understand the existing alloys and desing the new alloys using the relatively cheep theoretical calculations in contrast to experimental work.
The main findings are summarized in this article:
Zelený, M., Sedlák, P., Heczko, O., Seiner, H., Veřtát, P., Obata, M., … & Straka, L. (2021).
Effect of electron localization in theoretical design of Ni-Mn-Ga based magnetic shape memory alloys.
Materials & Design, 209, 109917.
https://doi.org/10.1016/j.matdes.2021.109917