  Thermally stable quantum states with multipartite entanglements led by
frustration are found in the antiferromagnetic spin-1/2 Heisenberg hexagon. The
model has been solved exactly to obtain all analytic expressions of eigenvalues
and eigenfunctions. Detection and characterizations for various types of
entanglements have been carried out in terms of concurrence and entanglement
witnesses based on several thermodynamic observables. Variations of
entanglement properties with respect to temperature and frustration are
discussed. Even though the frustration opposes the bipartite entanglement, it
favors the multipartite entanglement. Entangled states exhibit robustness
against the thermal effects in the presence of frustration and they are found
to survive at any temperature.
