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arXiv · 2501.08251

OstravaJ: a tool for calculating magnetic exchange interactions via DFT

Jan Priessnitz·Dominik Legut
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Abstract

OstravaJ is a Python package for high-throughput calculation of exchange interaction terms in the Heisenberg model for magnetic materials. It uses the total energy difference method, where calculations are based on the total energy of the system in different magnetic configurations, calculated by means of density functional theory. OstravaJ can propose a suitable set of magnetic configurations, generate VASP configuration files in cooperation with the user, and read VASP calculation results, which minimizes necessary human interaction. It can also calculate other relevant properties (e. g. MFA and RPA critical temperature, spin-wave stiffness) and provide input for various atomistic spin dynamics codes. We present results for a number of materials from various classes (metals, transition metal oxides), compared to other methods. They show that the total energy difference method is a useful method for exchange interaction calculation from first principles.

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Jan Priessnitz, Dominik Legut. 2025-01-14. OstravaJ: a tool for calculating magnetic exchange interactions via DFT. https://arxiv.org/abs/2501.08251

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