We investigate the phase behavior of tetrapods, hard non-convex bodies formed
by 4 rods connected under tetrahedral angles. We predict that, depending on the
relative lengths of the rods these particles can form a uniaxial nematic phase,
and more surprisingly they can exhibit a cubatic phase, a special case of the
biaxial nematic phase. These predictions may be experimentally testable, as
experimental realizations of tetrapods have recently become available.Comment: 8 pages ReVTeX 4, including 3 EPS figure