Piezoelectricity of A3BC3D2O14 structure crystals

First-principle calculations are performed to reveal the microscopic origin of piezoelectricity of ordered crystals with A3BC3D2O14 structure. The calculated piezoelectric constant e11 and atomistic piezoelectric contribution from every single atom type in a primitive cell of Sr3NbGa3Si2O14 (SNGS), Sr3TaGa3Si2O14 (STGS), Ca3NbGa3Si2O14 (CNGS), and Ca3TaGa3Si2O14 (CTGS) structures showed that the piezoelectricity comes mostly from one of three atoms in A positions. The percentages of the contributions from the A positions to the total internal piezoelectric constant exceed 69% in CNGS and CTGS and 81% in SNGS and STGS, respectively.