The possibility of stabilizing the unstable acepentalene (acp) molecule through coordination to transition metals is investigated by means of DFT calculations. Comparison with related experimentally known pentalene complexes indicate that their acp homologues are just slightly less stable, suggesting that they could be synthesized and isolated. Other original mono- and trinuclear species, such as M(acp)(2) (M = Zr, Hf), Co-3(acp)(2)(-), and Nb-3(acp)(2)(+), are also predicted to be stable.