  Recent development in two-dimensional (2D) magnetic materials have motivated
the search for new van der Waals magnetic materials, especially Ising-type
magnets with strong magnetic anisotropy. Fe-based MPX3 (M = transition metal, X
= chalcogen) compounds such as FePS3 and FePSe3 both exhibit an Ising-type
magnetic order, but FePSe3 receives much less attention compared to FePS3. This
work focuses on establishing the strategy to engineer magnetic anisotropy and
exchange interactions in this less-explored compound. Through chalcogen and
metal substitutions, the magnetic anisotropy is found to be immune against S
substitution for Se whereas tunable only with heavy Mn substitution for Fe. In
particular, Mn substitution leads to a continuous rotation of magnetic moments
from the out-of-plane direction towards in-plane. Furthermore, the magnetic
ordering temperature displays non-monotonic doping dependence for both
chalcogen and metal substitutions but due to different mechanisms. These
findings provide deeper insight into the Ising-type magnetism in this important
van der Waals material, shedding light on the study of other Ising-type
magnetic systems as well as discovering novel 2D magnets for potential
applications in spintronics.
