Semiconductors with both magnetic and optoelectronic properties are relevant for novel spintronic devices. With the aim of discovering new magnetic semiconductors, NU-MRSEC IRG-2 performed synthesis investigations on mixed halide-chalcogenides, resulting in the discovery of the new compound BaFMn0.5Te. This heteroanionic material contains magnetic ions in a layered heterostructure with alternating positive [BaF]+ and negative [Mn0.5Te]- layers. An in situ powder X-ray diffraction study of the synthesis path was conducted to determine the formation mechanism of BaFMn0.5Te. BaFMn0.5Te has strong red photoluminescence (~700 nm) and concurrent antiferromagnetism below 90 K. Theoretical analysis indicates that both of these properties derive from the unique Mn atom ordering pattern and the mixed F/Te anion nature of the system. This work provides confirmation that heteroanionic materials can exhibit unexpected and rare combinations of properties.
