  The spin Hall effect (SHE) is highly promising for spintronic applications,
and the design of materials with large SHE can enable ultra-low power memory
technology. Recently, 5d-transition metal oxides have been shown to demonstrate
a large SHE. Here we report large values of SHE in four 5d-transition metal
anti-perovskites which makes these anti-perovskites promising spintronic
materials. We demonstrate that these effects originate in the mixing of dx2-y2
and dxy orbitals caused by spin orbit coupling.
