“…By looking for approaches to control and optimize the plasma composition one has to consider self-consistently the behaviour of both hydrogen isotopes in the core and at the edge including the edge transport barrier (ETB), scrape-off layer (SOL) and divertor volume. In this paper an attempt to perform such an optimization is undertaken by taking into account, additionally to the effects mentioned above, the following aspects: in the ETB, where anomalous transport is strongly reduced, the neoclassical one will be most probable in plateau and banana regimes but not in the Pfirsch-Schlüter regime which was relevant to the conditions considered in [4]; the densities of neutral and charged particles in the SOL, which provide boundary conditions for the profile calculations in the plasma core, may be strongly non-stoichiometric, in particular, due to thermal forces arising with temperature gradients along the magnetic field [8]; in a divertor tokamak with X-point(s) the position where neutral particles enter the confined plasma volume through the separatrix affects significantly the neutral penetration process and, thus, the density profiles of charged particles in the plasma core [9]. The rest of this paper is organized as follows.…”