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Effect of electron localization in theoretical design of Ni-Mn-Ga based magnetic shape memory alloys

SYSNO ASEP	0543903
Document Type	J - Journal Article
R&D Document Type	Journal Article
Subsidiary J	Článek ve WOS
Title	Effect of electron localization in theoretical design of Ni-Mn-Ga based magnetic shape memory alloys
Author(s)	Zelený, M. (CZ) Sedlák, Petr (UT-L)_{RID, ORCID} Heczko, Oleg (FZU-D)_{RID, ORCID} Seiner, Hanuš (UT-L)_{RID, ORCID} Veřtát, Petr (FZU-D)_{RID, ORCID} Obata, M. (JP) Kotani, T. (JP) Oda, T. (JP) Straka, Ladislav (FZU-D)_ORCID
Number of authors	9
Article number	109917
Source Title	Materials and Design. - : Elsevier - ISSN 0264-1275 Roč. 209, November (2021)
Number of pages	10 s.
Publication form	Print - P
Language	eng - English
Country	GB - United Kingdom
Keywords	martensitic transformation ; magnetic shape memory alloys ; phase stability ; electron localization ; Ab initio calculations ; exchange-correlation energy
Subject RIV	BM - Solid Matter Physics ; Magnetism
OECD category	Condensed matter physics (including formerly solid state physics, supercond.)
Subject RIV - cooperation	Institute of Physics - Solid Matter Physics ; Magnetism
R&D Projects	GA21-06613S GA ČR - Czech Science Foundation (CSF)
	LM2018096 GA MŠMT - Ministry of Education, Youth and Sports (MEYS)
Method of publishing	Open access
Institutional support	UT-L - RVO:61388998 ; FZU-D - RVO:68378271
UT WOS	000697472400001
EID SCOPUS	85108964394
DOI	10.1016/j.matdes.2021.109917
Annotation	The precise determination of the stability of different martensitic phases is an essential task in the successful design of (magnetic) shape memory alloys. We evaluate the effect of electron delocalization correction on the predictive power of density functional theory for Ni-Mn-Ga, the prototype magnetic shape memory compound. Using the corrected Hubbard-model-based generalized gradient approximation (GGA+U), we varied the Coulomb repulsion parameter U from 0 eV to 3 eV to reveal the evolution of predicted material parameters. The increasing localization on Mn sites results in the increasing stabilization of 10M modulated structure in stoichiometric Ni2MnGa in agreement with experiment whereas uncorrected GGA and meta-GGA functional provide the lowest energy for 4O modulated structure and non-modulated structure, respectively. GGA+U calculations indicate that 10M structure is more stable than other martensitic structures for U > 1.2 eV. The key features of density of states (DOS) responsible for the stabilization or destabilization of particular martensitic phases calculated with GGA+U are found also in DOS calculated with advanced quasi-particle self-consistent GW (QSGW) method. It supports the physical background of Hubbard correction. Moreover, the calculations with U = 1.8 eV provide the best agreement with experimental data for lattice parameters of stoichiometric and off-stoichiometric alloys.
Workplace	Institute of Thermomechanics
Contact	Marie Kajprová, kajprova@it.cas.cz, Tel.: 266 053 154 ; Jana Lahovská, jaja@it.cas.cz, Tel.: 266 053 823
Year of Publishing	2022
Electronic address	https://www.sciencedirect.com/science/article/pii/S0264127521004706/pdfft?isDTMRedir=true&download=true

Number of the records: 1