Bio(-Inspired) Supramolecular Chemistry: Insights from quantum-chemical bonding analyses

Life on Earth as we know it would not be possible without hydrogen bonding. Hydrogen bonds are, for instance, crucial for the structure, replication, and expression of the DNA double helix and the secondary structure and thereby the eventual function of proteins. A hydrogen bond is an interaction between the partially positively charged hydrogen atom of a hydrogen-bond donor group [i.e., H(–O) or H(–N)] and a partially negatively charged hydrogen-bond acceptor group [i.e., O or N]. Hydrogen bonds are, however, not purely electrostatic, but also contain a significant covalent character (i.e., orbital interaction) in addition to steric Pauli repulsion and dispersion interaction. The appearance of hydrogen bonding as a crucial player in the bonding mechanisms encountered in biochemical systems inspired supramolecular chemists to incorporate intermolecular hydrogen bonding in the design of novel catalysts, (macro)molecules, and materials, and led to the emergence of the field of bio-inspired supramolecular chemistry. However, to rationally design new and improved molecules and materials, first a profound understanding of the mechanisms of intermolecular hydrogen bonding is required. Decoding Nature’s design principles not only enriches the understanding of fundamental (inter)molecular interactions but also opens new avenues for creating functional materials and devices with unprecedented properties. In this thesis, we aimed to develop a comprehensive understanding of the nature of the bonding mechanisms in biological and bio-inspired supramolecular systems, primarily based on hydrogen bonding, using quantum-chemical investigations in the framework of density functional theory (DFT). The findings outlined in this thesis show that experimentally obtained questions and phenomena regarding the structure and stability of bio(-inspired) supramolecular systems of significant size can nowadays be understood and explained from accurate quantum-chemical computations. The mechanistic insights into intermolecular chemical bonding acquired in this thesis can be applied as design principles for novel and improved bio(-inspired) supramolecular systems and materials with tailored properties.