Research Projects

The project aims to design new organic dielectric materials based on charge transfer (CT) in solid state, involving a donor (D) and an acceptor (A). The hypothesis is based on molecular rotation in molecular crystals, which plays a crucial role in modulating the magnitude of the dielectric constant. In-plane motion in crystals is easier if the non-covalent bonding between the donor and acceptor molecules is weak, affecting the orientational polarization and the dielectric constant. Experiments will involve chemochemical synthesis of CT cocrystals via solvent-drop grinding and crystallization using different methods. Single-crystal X-ray diffraction (SCXRD) will be used to characterize the grown single crystals, while powder X-ray diffraction (PXRD) will be used to establish phase purity. Different stoichiometric combinations of donors and acceptors will be attempted to achieve desired phase purity. The role of non-covalent interactions in the formation of the cocrystal will be quantitatively evaluated, including investigating the role of structural disorder. Solid-state 13C-NMR experiments will be performed to obtain atomistic insights into the role of structural disorder in the observed property, allowing for the determination of chemical shift anisotropy (CSA) tensor, spin-lattice relaxation time, and molecular correlation time of the different nuclei associated with the disorder in the crystal. These studies will contribute to understanding the factors at the atomic/molecular level that contribute to observed dielectric behavior and facilitate the design of new organic materials with improved dielectric response.