Magnetic hybrid transition metal halides

Abstract

Metal halide semiconductors (MHS) have gained significant attention in recent years due to their exceptional optoelectronic properties. While most MHS systems that are currently under investigation are nonmagnetic, the diverse chemical and structural properties of MHS offer a unique opportunity to incorporate magnetic spins, such as transition-metal ions, into the metal halide lattice. This enables the exploration of novel magnetic phenomena and exchange mechanisms, making MHS a promising platform for multifunctional magnetic materials. In this review, we provide an overview of the historic and recent developments in magnetic transition metal halides (TMHs) with different chemical and structural diversities, highlighting the structure–magnetic property relationships in terms of different structure dimensions and metal ions. We also discuss the potential for multifunctional magnetic TMHs, where magnetism co-exists or is coupled with a secondary property of interest, such as conductivity, ferroelectricity, optical absorption, and luminescence. These coupling effects enable the TMHs to be promising candidates for multifunctional materials.