Magnetic Circular Dichroism Elucidates Molecular Interactions in Aggregated Chiral Organic Materials
Alessio Gabbani, Andrea Taddeucci, Marco Bertuolo, Francesco Pineider, Laura Antonella Aronica, Lorenzo Di Bari, Gennaro Pescitelli, Francesco Zinna
Abstract
Chiral materials formed by aggregated organic compounds play a fundamental role in chiral optoelectronics, photonics and spintronics. Nonetheless, a precise understanding of the molecular interactions involved remains an open problem. Here we introduce magnetic circular dichroism (MCD) as a new tool to elucidate molecular interactions and structural parameters of a supramolecular system. A detailed analysis of MCD together with electronic circular dichroism spectra combined to ab initio calculations unveils essential information on the geometry and energy levels of a self-assembled thin film made of a carbazole di-bithiophene chiral molecule. This approach can be extended to a generality of chiral organic materials and can help rationalizing the fundamental interactions leading to supramolecular order. This in turn could enable a better understanding of structure-property relationships, resulting in a more efficient material design.