Electronic structure and magnetism in M(=IA, IIA)C compounds with the rocksalt structure

TL;DR

This study investigates the electronic and magnetic properties of MC compounds with rocksalt structure, revealing their potential as half-metals or magnetic semiconductors based on their electronic structures and magnetic moments.

Contribution

The paper provides first-principles calculations of electronic structures and magnetic properties of alkali and alkaline earth carbides with rocksalt structure, highlighting their magnetic behavior and potential applications.

Findings

SrC, BaC, and RaC are half-metals.

KC, RbC, and CsC are magnetic semiconductors.

Magnetic moments mainly originate from spin-polarized p-orbitals of carbon.

Abstract

Electronic structures of MC where M is the alkali and alkaline earth metals with the rocksalt structure are calculated by full potential density functional codes. We find that the spin magnetic moment in the compounds is mainly contributed by the spin polarized p-orbitals of carbon. The large distance between the carbon makes the p-orbitals localized, which induces magnetic instability according to the Stoner criterion. The electronic structure can be mapped to the rigid band model. SrC, BaC and RaC are half-metals, while KC, RbC and CsC are magnetic semiconductors