Enthalpies of formation of TM-X compounds (X=Al, Ga, Si, Ge, Sn). Comparison of ab-initio values and experimental data

Nowadays first-principles calculations have achieved considerable reliability for the prediction of the properties of materials. These calculations are based on the density functional theory. In the present work, we have obtained a large number of enthalpies of formation of binary intermetallic compounds of transition metals with the elements Al, Ga, Si, Ge or Sn. The ab-initio values have been calculated with VASP in the generalized gradient approximation. We have compared the calculated enthalpies of formation of compounds to the values obtained with calorimetric methods. An excellent agreement is observed in the cases of aluminum and silicon based compounds. We also observe that in the case of highly negative values of enthalpies of formation of early transition metal alloys the experimental values are often more negative than the calculated values but it is not the case in Pt based compounds. In the cases of the Pt, Mo, Ru, Rh compounds with Al, Ga, Si, Ge or Sn, a very nice agreement between calculated and experimental values is observed.