  We present a neutron diffraction study of FeV2O4, which is rare in exhibiting
spin and orbital degrees of freedom on both cation sublattices of the spinel
structure. Our data confirm the existence of three structural phase transitions
previously identified with x-ray powder diffraction, and reveal that the lower
two transitions are associated with sequential collinear and canted
ferrimagnetic transitions involving both cation sites. Through consideration of
local crystal and spin symmetry, we further conclude that Fe2+ cations are
ferro-orbitally ordered below 135K and V3+ orbitals order at 60K in accordance
with predictions for vanadium spinels with large trigonal distortions and
strong spin-orbit coupling. Intriguingly, the direction of ordered vanadium
spins at low temperatures obey `ice rules' more commonly associated with the
frustrated rare-earth pyrochlore systems.
