DFT Approaches for Smart Materials with Ferroelectric Properties

In the last decades, the development of new technologies is strongly related to materials development, mainly for semiconductors and smart materials. A common property usually observed in both materials is the ferroelectricity. The ferroelectric materials are largely employed on data storage and memory devices, sensors, actuators, and others. In summary, the ferroelectricity is evidenced by a high spontaneous polarization inside the crystalline structure, which can arise from crystal modifications, such as, structural distortions, chemical bond profile, or material composition. Nowadays, the more important ferroelectric materials are the BaTiO₃, PbTiO₃, PbZr_xTi_1-xO₃ (PZT), and BiFeO₃ materials. In addition, the search for lead-free ferroelectric materials has attracted a big interest from scientists around the world aiming at environmentally friendly alternatives. As for lead-free materials as for Pb-based ferroelectric materials, several experimental approaches are widely reported. However, the investigation of this kind of material through theoretical investigation still represents a challenge. Therefore, this work presents theoretical approaches based on the Density Functional Theory (DFT) demonstrating its potential to develop advanced materials. Thereby, the theoretical methodology has successfully employed for clarification or prediction of the ferroelectric properties raised by chemical modifications or structural deformations.