This software package allows you to obtain full second-order elastic tensors (elastic constants) for all crystal lattice types, and third-order elastic-constants for cubic, hexagonal, and rhombohedral crystals. ElaStic is written in Python and uses the SGROUP[1] tool as symmetry and space-group calculator. It is interfaced with the density-functional codes exciting, Wien2k, and Quantum Espresso for energy and stress calculations. Further information is found in the following reference:

R. Golesorkhtabar, P. Pavone, J. Spitaler, P. Puschnig, and Claudia Draxl, “ElaStic: A tool for calculating second-order elastic constants from first principles, Computer Physics Communications 184 (2013) 1861–1873

[1] B. Z. Yanchitsky and  A. N. Timoshevskii, “Determination of the space group and unit cell for a periodic solid”, Comp. Phys. Comm., ELSEVIER SCIENCE BV, 2001, 139, 235-242