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Helical aromatic oligoamide foldamers (1a–c) with tunable lengths were computationally examined for their ability to bind selected sugars and sugar alcohols. These helices feature cylindrically shaped inner cavities lined with multiple inward-facing amide carbonyl oxygens acting as hydrogen-bond acceptors, enabling sugar binding via hydrogen bonding. Each of the helical foldamers has an overall dipole moment that increases with the length of the helix. The binding of a guest typically results in a reduction of the overall helix dipole moment within the complex, although there are several exceptions. The strength of host–guest interactions correlated positively with the number of hydrogen bonds formed. Longer helix 1c showed stronger interaction energies (up to −84.45 kcal mol−1), particularly with disaccharides, while shorter helix 1a bound sugars more weakly due to fewer established hydrogen bonds. The helical hosts exhibit structural adaptibility upon binding guests, with host distortion upon binding decreased with increasing helix length. Despite reduced binding energies, the complexes retained binding capability in aqueous environments, demonstrating their viability for aqueous-phase applications. This study underscores the critical roles of helical length and dipole alignment in optimizing sugar binding, providing a theoretical foundation for designing synthetic receptors for sugars and sugar alcohols based on aromatic oligoamide foldamers. 

The relationship between covalent and supramolecular bonding, and the criteria of the assignments of different interactions were explored via the review of selenium and tellurium containing structures in the Cambridge Structural Database and their computational analysis using Quantum Theory of Atoms in Molecules (QTAIM). This combined study revealed continuums of the interatomic Se⋯Br and Te⋯I distances, d Ch⋯X , in the series of associations from the sums of the van der Waals radii of these atoms ( r Ch + r X ) to their covalent bond lengths. The electron densities, ρ ( r ), at Bond Critical Points (BCPs) along the chalcogen bond paths increased gradually from about 0.01 a.u. common for the non-covalent interactions to about 0.1 a.u. typical for the covalent bonds. The log  ρ ( r ) values fell on the same linear trend line when plotted against normalized interatomic distances, R XY = d Ch⋯X /( r Ch + r X ). The transition from the positive to negative values of the energy densities, H ( r ), at the BCPs (related to a changeover of essentially non-covalent into partially covalent interactions) were observed at R XY ≈ 0.80. Synchronous changes of bonding characteristics with R XY (similar to that found earlier in the halogen-bonded systems) designated normalized interatomic separation as a critical factor determining the nature of these bondings. The uninterrupted continuums of Te⋯I and Se⋯Br bond lengths and BCPs’ characteristics signified an intrinsic link between limiting types of bonding involving chalcogen atoms and between covalent and supramolecular bonding in general.