Résumé
α-Quartz-type MIIIXVO4 compounds (M = B, Al, or Ga; X = P or As) are piezoelectric materials, which can be considered as alternatives to α-quartz. Although a correlation between their structure and their piezoelectric properties has been empirically derived from experimental data, the microscopic origin of their piezoelectric efficiency is not clearly understood. Here, we use the density functional perturbation theory to understand the mechanism and origin of the piezoelectric effect in the MXO4 family. This theoretical understanding is of primary importance in the research on new MXO4 compounds with optimized piezoelectric properties.