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Hydrogen‐bonded organic frameworks (HOFs) with low densities and high porosities are rare and challenging to design because most molecules have a strong energetic preference for close packing. Crystal structure prediction (CSP) can rank the crystal packings available to an organic molecule based on their relative lattice energies. This has become a powerful tool for the a priori design of porous molecular crystals. Previously, we combined CSP with structure‐property predictions to generate energy‐structure‐function (ESF) maps for a series of triptycene‐based molecules with quinoxaline groups. From these ESF maps, triptycene trisquinoxalinedione (TH5) was predicted to form a previously unknown low‐energy HOF (TH5‐A) with a remarkably low density of 0.374 g cm−3 and three‐dimensional (3D) pores. Here, we demonstrate the reliability of those ESF maps by discovering this TH5‐A polymorph experimentally. This material has a high accessible surface area of 3,284 m2 g−1, as measured by nitrogen adsorption, making it one of the most porous HOFs reported to date. [ABSTRACT FROM AUTHOR]

Ethyl acetate is an important chemical raw material and solvent. It is also a key volatile organic compound in the brewing industry and a marker for lung cancer. Materials that are highly selective toward ethyl acetate are needed for its separation and detection. Here, we report a trianglimine macrocycle (TAMC) that selectively adsorbs ethyl acetate by forming a solvate. Crystal structure prediction showed this to be the lowest energy solvate structure available. This solvate leaves a metastable, "templated" cavity after solvent removal. Adsorption and breakthrough experiments confirmed that TAMC has adequate adsorption kinetics to separate ethyl acetate from azeotropic mixtures with ethanol, which is a challenging and energy‐intensive industrial separation. [ABSTRACT FROM AUTHOR]

A hydrogen-bonded framework that was predicted to have 3-D porosity has been discovered experimentally by Anna G. Slater, John W. Ward, Marc A. Little, Andrew I. Cooper et al. in their Research Article (e202303167). It is one of the most porous hydrogen-bonded frameworks synthesized to date. Frontispiece: Experimental Confirmation of a Predicted Porous Hydrogen-Bonded Organic Framework. [Extracted from the article]

Keywords: crystal structure prediction; dynamic separation; macrocycles; molecular crystals; selective adsorption EN crystal structure prediction dynamic separation macrocycles molecular crystals selective adsorption 10486 10486 1 07/27/21 20210721 NES 210721 B Guided by crystal structure prediction b , a "templating" strategy was used to construct selective binding sites in a trianglimine macrocycle crystal for ethyl acetate, an important chemical raw material and solvent. Crystal structure prediction, macrocycles, molecular crystals, selective adsorption, dynamic separation The resulting molecular crystals exhibit inherently high selectivity towards ethyl acetate, and hence can separate ethyl acetate from azeotropic mixtures with ethanol. [Extracted from the article]