Comparison of the final elemental surface distributions [X/Fe] (solid lines) obtained after the development of the neutron-capture processes in a 2 M_⊙ AGB star of metallicity [Fe/H] = −0.5. The blue line is obtained with diffusive mixing characterized by ƒ_env = 0.14 and ƒ_env = 0.03, which gives rise to s-process nucleosynthesis, while the red line results from mixing with ƒ_env = 0.06 and ƒ_pulse = 0.06 leading to a PIE, i.e., to a i-process nucleosynthesis.