First-Principles Calculation of the Vacancy Formation Energy in VC

The ab inttio density functional theory had been used to calculate the vacancy formation energy of C in the vanadium carbide, to reveal the effects of super-cell size and parameters k points. It turned out that, the calculation model of C vacancy formation energy in VC should be contain 64 atoms, while the K grid meshed 5x5x5 above using the Monkhorst-Pack method. And due to the vacancy formation energy of C 6.76eV, the high vacancy concentration of VC could be caused by simple thermal vibration. These researches not only had a certain value to know VC properties, but also had great significance to rediscover the forming of vacancy.