An investigation was made, of the carbon monovacancy in Ta4AlC3, using firstprinciples

calculations. The 2a sites were identified as being the probable carbon

vacancy sites in Ta4AlC3; based upon the energetics of vacancy formation. It was

found that introducing carbon vacancies decreased the phase stability of Ta4AlC3.

There were no significant changes in volume upon introducing a carbon vacancy.

However, the bulk modulus decreased upon introducing a carbon vacancy. The

differences in density of states of Ta4AlC3 with and without carbon vacancies were

analyzed. Some vacancy peaks were observed near to the Fermi level. The density

of states at the Fermi level increased upon introducing carbon vacancies, and was

suggested to be of benefit to electron transport in Ta4AlC3.

First-Principles Study of Carbon Vacancy in Ta4AlC3. Y.L.Du, Z.M.Sun,

H.Hashimoto, W.B.Tian: Materials Transactions, 2008, 49[9], 1934-6