Gibbs free energy per nucleon for accreted NS crust (renormalised to that of catalysed matter) for nuclear clusters with different Z, as predicted by the model of MB (lower panel) and the ETFSI model with the BSk20 EDF (upper panel). With increasing pressure (P₁ <  P₂ <  P₃), the energetically preferred value for Z decreases. For BSk20 (P₁, P₂, P₃)=(0.82, 1.22, 2.6)⋅10³⁰ erg cm⁻³, for MB (bottom panel) (P₁, P₂, P₃)=(1.03, 1.28, 1.54)×10³⁰ erg cm⁻³. Solid dots represent stable clusters at given pressure whereas circles denote the parent clusters for the last reactions just before the given pressure is reached.