Molecular Ferroelectrics

Ferroelectrics are materials which display a permanent polarisation that can be switched by an external electric field. They find a number of applications in devices such as capacitors, ferroelectric memories, in field effect transistors and, via the related piezoelectric effect, in positioners and transducers. The majority of ferrelectrics used practically are based on heavy-metal containing inorganic oxides such as BaTiO3, PbTi1-xZrxO3, which have drawbacks such as high processing temperatures and potential toxicity. This project will explore methods that our group has developed to try and identify new molecular ferroelectrics which would avoid these issues. In particular we have developed automated symmetry-searching methods allowing us to mine through the >1,000,000 known crystal structures to identify materials that might display ferroelectricity. The most promising candidate materials from this data searching will be synthesised and their properties studied by a variety of experimental methods. The potential advantages of molecular ferroelectrics include their ease of synthesis and processing, low toxicity and the possibility of producing flexible materials compatible with organic electronics. The student will receive training in crystallography (both single crystal and powder), computational methods, materials synthesis, and dielectric property measurements.