Thermohaline diffusion coefficient, D_thc, and total rotation diffusion coefficient, D_rot, (solid and dashed lines respectively) as a function of reduced stellar mass, δM ( at the base of the hydrogen-burning shell, M_HBS; δM = 1 at the base of the convective envelope, M_BCE) for 1.25 M_⊙ models at different metallicities. In each case the evolution point is chosen at the luminosity when thermohaline mixing connects the hydrogen-burning shell with the convective envelope (see text).