A Permanently Porous Chalcogen-Bonded Organic Framework with an Unprecedented Ensemble of Adsorption, Assembly, Dynamics, and Electronic Properties

The nature of connectivity between constituent atomic or molecular building blocks is fundamental in shaping the properties and functionality of materials. Indeed, the extrapolation of emergent interatomic interactions to enable functional materials has driven transformative technological advancements. However, the toolbox of bonding interactions employed in material design has remained largely static since the emergence of dynamic covalent chemistry some 30 years ago. Here, we demonstrate that noncovalent chalcogen bonding (Ch-bonding) is a fundamentally new mode of interatomic connectivity for constructing functional materials by design. This is demonstrated by leveraging the high-fidelity, self-complementary assembly of 1,2,5-telluradiazole moieties to construct a honeycomb-type permanently porous chalcogen-bonded organic framework (ChOF), assembled and stabilized solely through noncovalent Te···N contacts. Empirical and computational studies of gas adsorption, structural healing, lattice dynamics, and electronic structure reveal an unprecedented collection of attributes arising directly from the unique nature of the Te···N Ch-bonding. In addition to introducing a distinct class of permanently porous frameworks, this work reveals Ch-bonding to be an emergent and unique tool for the construction of functional materials with never-before-seen ensembles of properties and behaviors.