Experimental cohesive energies were quite often used as bulk energies in semi-empirical or empirical modeling of transition metal and alloy properties (e.g. in TB-SMA, the EAM, the bond order simulation (BOS) model, etc.), thus ignoring the free-atom spin-polarizations and promotion energy contributions. The importance of employing corrected cohesion energy in avoiding erroneous results is emphasized, especially for alloys with similar cohesion energies of the constituents. We demonstrate the effect of the correction in the prediction of equilibrium compositional structures and thermodynamical properties of cuboctahedral 55 atom Pt–Rh nanoclusters.