Study of Magnetism and Electronic Structures of Compounds with CoAs Layers

Abstract

To understand magnetism and electronic structures of compounds with CoAs layers, we compared results of experiments and band calculations of LiCoAs, LaCoAsO, and Sr₂ScO₃CoAs, which are all in the tetragonal crystal structure with the space group of P4/nmm. As a result of synthesis and magnetic measurement, we newly found that LiCoAs shows the Pauli paramagnetism with a small exchange-enhancement. Results of band calculations of three compounds are consistent with the experimental ones. Band structures show that magnetism of compounds with CoAs layers is strongly influenced by the distance between Co atoms within CoAs layer and thickness of it, while the interlayer distance of CoAs layers and the components of in-between layers less influence on their magnetism.