CrPS4（Chromium Phosphorus Sulfide）

Chromium thiophosphate (CrPS₄) is an emerging two-dimensional (2D) van der Waals magnetic material, belonging to the family of transition metal chalcogenophosphates. It crystallizes in a monoclinic structure with the space group C2/m (No. 12). The crystal consists of alternating layers of CrS₆ octahedra and PS₄ tetrahedra, with van der Waals interactions between layers, enabling exfoliation into nanoscale thin sheets. Each Cr atom is octahedrally coordinated by six S atoms, forming a stable magnetic framework, while P atoms form covalent tetrahedral units with S atoms, providing lattice stability.

Magnetically, CrPS₄ is a two-dimensional antiferromagnet. Bulk CrPS₄ exhibits intralayer ferromagnetic alignmentwith interlayer antiferromagnetic coupling, and its Néel temperature is approximately 36–40 K. The magnetic properties are highly anisotropic, and the weak interlayer coupling allows for tunable magnetic behavior under external magnetic fields, strain, or carrier doping, enabling magnetic phase transitions and spin manipulation.

In terms of electronic structure, CrPS₄ is a semiconductor with an indirect bandgap of approximately 1.4–1.6 eV, which varies slightly with thickness and strain. Its optical absorption covers the visible to near-infrared range, exhibiting strong photoresponse. Unlike air-sensitive 2D magnetic materials such as CrI₃, CrPS₄ is chemically stable under ambient conditions, facilitating experiments and device integration.

Due to its stable layered structure, tunable magnetism, and semiconducting nature, CrPS₄ shows promising potential for applications in spintronics, magneto-optical devices, photodetectors, and 2D magnetic heterostructures.