VelCrys: Interactive web-based application to compute acoustic wave velocity in crystals and its magnetic corrections

We present VelCrys, a web-based interactive tool, that allows to perform further post-processing of the elastic tensor in order to compute and plot the group velocity of the acoustic waves for any crystal symmetry. We also implemented the calculation of effective magnetic corrections to the elastic tensor and corresponding fractional change in group velocity under a magnetic field. We apply it to dry sandstone, cubic CoPt and hcp Co to show some of the program features. In the analysis of magnetic corrections, we find complex landscapes of fractional change in group velocity as a function of ray direction, as well as a field dependence consistent with Simon effect.