First-principles computation of second-order elastic constants and equations of state for tetragonal BaTiO3

First-principles computational techniques are employed for computing the second-order elastic constants (SOEC) and equations of state for the tetragonal phase of BaTiO3. The bulk modulus is computed by two independent methods and compared with experiment. A variety of potentials and basis sets are used. The impact on the computational values due to the potentials, basis sets, and the crystalline geometry optimization is discussed.