Date of Award
Open Access Honors Thesis
Dr. Aaron S. Rury
Ferroelectrics are a group of materials possessing the unique chemical property of being able to switch their electrical polarity when exposed to an electric field. This property makes ferroelectrics a promising field of study with the potential to impact various future technologies in information and energy storage, as well as quantum mechanics. Understanding molecular structures of ferroelectric (and opposite anti-ferroelectric) materials, and how they relate to the compound’s properties is essential to harnessing the potential these materials carry. The report discusses analysis of anti-ferroelectric material trifluoromethylbenzimidazole (TFMBI), by subjecting the compound to various physical and computational chemistry techniques at varying temperatures. This information can help to understand how intramolecular changes in the TFMBI crystal structure relate to larger-scale changes in the material.
X-ray diffraction was first used to determine the molecular structure within synthesized TFMBI crystals. Raman spectroscopic data was then collected and compared with theoretical data from Crystal 17 software. If the data matched, parameters for the data were input into Jmol software to predict which peaks of spectroscopic data corresponded to which molecular bonds. Finally, Gaussian software mapped electron density. From this point, the vibrational changes in specific bonds could be related to shifts in electron density throughout the molecule.
It was found that as temperature was lowered, electron density was transferred out of the N—H bond, and this removed electron density was channeled into the adjacent double bond of the imidazole ring, as well as both the double and single bonds of the nearby benzene ring. This shifting in electron density caused stretching and compressing of the bonds throughout the molecule, resulting in polarization of the electric field of the molecule.
Bhullar, Kanwar, "The Analysis of Trifluoromethylbenzimidazole (TFMBI) Crystals Using Physical Chemistry Techniques to Explain Ferroelectric and Anti-Ferroelectric Properties of the Compound" (2019). Honors College Theses. 58.