Multichannel three-body model of Li6

The binding energies of the lowest isospin singlet (Jπ=1+) and triplet (Jπ=0+) states of Li6 are calculated on a multichannel three-body model in which the internal structure of the α particle is approximately represented by a two-state system. The n-α interaction is given by a two-channel l-dependent potential that is obtained by fitting low-energy scattering data. The np interaction is taken to be the Pease-Feshbach potential. The Faddeev equations are generalized to allow spin and internal structure of the particles and are solved in the separable t-matrix approximation for bound-state energies. The results obtained are in good agreement with experiments and the effect of the α internal structure is discussed.