Structural and chemical disorder in Ni$_2$MnGa Heusler alloy investigated by nuclear magnetic resonance

TL;DR

This study uses NMR and DFT to analyze local structural and chemical disorder in Ni-Mn-Ga Heusler alloys, revealing defect types and their microscopic nature.

Contribution

It combines NMR experiments with DFT calculations to provide a detailed microscopic understanding of local disorder in Ni-Mn-Ga alloys.

Findings

Significant structural defects detected in NMR experiments.

Defects interpreted as antisite defects or anti-phase boundaries.

Provides a consistent microscopic description of local disorder.

Abstract

The local environment of Mn atoms in stoichiometric Ni-Mn-Ga Heusler alloys was investigated using Nuclear Magnetic Resonance (NMR) and interpreted with the help of Density Functional Theory (DFT) methods. In cubic austenite, the significant amount of structural defects was observed in \mn NMR experiments and interpreted using DFT calculations as individual antisite defects or defects accompanying anti-phase boundaries. Combined NMR and DFT analysis provides a consistent microscopic description of local disorder in Ni-Mn-Ga.