  We use monomer-resolved numerical simulations to study the positional and
orientational structure of a dense dendrimer solution, focusing on the effects
of dendrimers' prolate shape and deformability on the short-range order. Our
results provide unambiguous evidence that the nearest-neighbor shell of a
tagged particle consists of a mixture of crossed, side-by-side, side-to-end,
and end-to-end pair configurations, imposing antinematic rather than nematic
order observed in undeformable rodlike particles. This packing pattern persists
even at densities where particle overlap becomes sizable. We demonstrate that
the antinematic arrangement is compatible with the A15 crystal lattice reported
in several dendrimer compounds.
