First-principles studies on Ti3Si0.5Ge0.5C2 under pressure

The structural, electronic and elastic properties of Ti3Si0.5Ge0.5C2 have been investigated by using the pseudopotential plane-wave method within the density-functional theory. Our calculated equation of state (EOS) is consistent with the experimental results. The density of states (DOS) indicates that Ti3SixGe1−xC2 ( x = 0 , 0.5, 1.0) are metallic, and these compounds have nearly the same electrical conductivity. The elastic constants for Ti3Si0.5Ge0.5C2 are obtained at zero pressure, which is compared to Ti3SiC2 and Ti3GeC2. We can conclude that Ti3Si0.5Ge0.5C2 is brittle in nature by analyzing the ratio between bulk and shear moduli. There appears to be little effect on the electronic and elastic properties with the Ge substitution to Si atoms in Ti3SiC2.