Abstract
The description of the nucleus 6Li as a two-cluster structure (4He-2H) is compared with two more complicated models: (i) the interplay of two-cluster configurations (4He-2H)+(5Li-n)+(5He-p) and (ii) the three-cluster model (4He-p-n). Both models provide significant gains in the ground-state binding energy of 1.1 and 1.5 MeV, respectively, when a central two-body effective interaction is used. Implications for the improvement of the description of 6Li are discussed.