Magnetic properties of Fe$_{1-x}$Ni$_x$ alloy from CPA+DMFT perspectives

TL;DR

This study uses CPA+DMFT methods to analyze the magnetic properties of Fe-Ni alloys, successfully matching experimental susceptibilities and magnetic moments, and revealing potential high-spin to low-spin transitions at elevated temperatures.

Contribution

It introduces a first-principles approach combining CPA and DMFT to accurately model magnetic behaviors of Fe-Ni alloys, including spin state transitions.

Findings

Magnetic susceptibilities follow Curie-Weiss behavior.

Magnetic moments align with experimental trends.

Possible high-spin to low-spin transitions at high temperatures.

Abstract

We use a combination of the coherent potential approximation and dynamical mean field theory to study magnetic properties of the Fe$_{1-x}$Ni$_x$ alloy from a first principles. Calculated uniform magnetic susceptibilities have a Curie-Weiss-like behavior and extracted effective temperatures are in agreement with the experimental results. The individual squared magnetic moments obtained as function of nickel concentration follow the same trends as experimental data. An analysis of the ionic and spin weights shows a possibility of a high-spin to intermediate- and low-spin states transitions at high temperatures.