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

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F21%3A00543903" target="_blank" >RIV/68378271:_____/21:00543903 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61388998:_____/21:00543903 RIV/00216305:26210/21:PU142398 RIV/00216208:11320/21:10434378

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0264127521004706" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0264127521004706</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.matdes.2021.109917" target="_blank" >10.1016/j.matdes.2021.109917</a>

Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

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.

Název v anglickém jazyce

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

Popis výsledku anglicky

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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Materials and Design

ISSN

0264-1275

e-ISSN

1873-4197

Svazek periodika

209

Číslo periodika v rámci svazku

November

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

109917

Kód UT WoS článku

000697472400001

EID výsledku v databázi Scopus

2-s2.0-85108964394