# Computational search for Dirac and Weyl nodes in $f$-electon antiperovskites

## TL;DR

This study uses ab initio density functional theory calculations to identify potential Dirac and Weyl semimetals in lanthanide antiperovskites, revealing promising candidates with bulk Dirac states near the Fermi level.

## Contribution

It introduces a computational approach to discover Dirac and Weyl nodes in lanthanide antiperovskites, including compounds not yet synthesized.

## Key findings

- Several lanthanide antiperovskites host bulk Dirac states near the Fermi level.
- Massive three-dimensional Dirac states are found in A3BO compounds with A=Sm, Eu, Gd, Yb.
- Magnetic Eu3BO compounds exhibit Weyl nodes due to lifted Dirac node degeneracy.

## Abstract

We present the result of an \textit{ab initio} search for new Dirac materials among inverse perovskites. Our investigation is focused on the less studied class of lanthanide antiperovskites containing heavy $f$-electron elements in the cation position. Some of the studied compounds have not yet been synthesized experimentally. Our computational approach is based on density functional theory calculations which account for spin-orbit interaction and strong correlations of the $f$-electron atoms. We find several promising candidates among lanthanide antiperovskites which host bulk Dirac states close to the Fermi level. Specifically, our calculations reveal massive three-dimensional Dirac states in materials of the class A$_3$BO, where A=Sm, Eu, Gd, Yb and B=Sn, Pb. In materials with finite magnetic moment, such as Eu$_3$BO (B=Sn, Pb), the degeneracy of the Dirac nodes is lifted, leading to appearance of Weyl nodes.