First principles calculations of the stability of the T2 and D88 phases in the V–Si–B system

• First principles calculations in the V–Si–B system.
• The enthalpies of formation of the T2 and D88 ternary compounds have been obtained.
• The electronic densities of states of the ternary compounds have been computed.
• The isothermal section of the V–Si–B system has been calculated at 298.15 K.

The crystal and electronic structures of D8l-V5SiB2 and D88-V5Si3B ternary compounds have been investigated by means of first principle calculations. The calculated structural parameters are in very good agreement with the experimental data. The calculated values of the enthalpies of formation at T = 0 K of the D8l-V5SiB2 and D88-V5Si3B ternary compounds are −67.1 and −62.1 kJ/mol of atoms respectively. The total and partial electronic densities of states show a strong hybridization between the B p states and V d states. The defect enthalpies of formation as well as the mixing enthalpies have been computed. These data are essential for the modeling of the D8l and D88 phases in the V–Si–B ternary system. A partial V–VSi2–VB isothermal section at 298 K is proposed.

Ab-initio calculation of the isothermal section of the V–Si–B system at 298.15 K.Figure optionsDownload as PowerPoint slide