Many of the known examples of half-metals are oxides, sulfides, or Heusler alloys.
[1] Types of half-metallic compounds theoretically predicted so far include some Heusler alloys, such as Co2FeSi, NiMnSb, and PtMnSb; some Si-containing half–Heusler alloys with Curie temperatures over 600 K, such as NiCrSi and PdCrSi; some transition-metal oxides, including rutile structured CrO2; some perovskites, such as LaMnO3 and SeMnO3; and a few more simply structured zincblende (ZB) compounds, including CrAs and superlattices.
NiMnSb and CrO2 have been experimentally determined to be half-metals at very low temperatures.
This results in conducting behavior for only electrons in the first spin orientation.
[2] Half-metals were first described in 1983, as an explanation for the electrical properties of manganese-based Heusler alloys.