Digital navigation of energy-structure-function maps for hydrogen-bonded porous molecular crystals

Energy-structure-function (ESF) maps can aid the targeted discovery of porous molecular crystals by predicting the stable crystalline arrangements along with their functions of interest. Here, we compute ESF maps for a series of rigid molecules that comprise either a triptycene or a spiro-biphenyl core, functionalized with six different hydrogen-bonding moieties. We show that the positioning of the hydrogen-bonding sites, as well as their number, has a profound influence on the shape of the resulting ESF maps, revealing promising structure-function spaces for future experiments. We also demonstrate a simple and general approach to representing and inspecting the high-dimensional data of an ESF map, enabling an efficient navigation of the ESF data to identify 'landmark' structures that are energetically favourable or functionally interesting. This is a step toward the automated analysis of ESF maps, an important goal for closed-loop, autonomous searches for molecular crystals with useful functions. Energy-structure-function (ESF) maps can facilitate functional materials discovery. Here the authors provide a protocol for the digital navigation of ESF maps, as demonstrated for hydrogen-bonded organic frameworks constructed from triptycene- and spiro-biphenyl-based molecular building block.

Automated summary

Energy-structure-function (ESF) maps can facilitate the discovery of functional materials by predicting stable crystalline arrangements and functions of interest. The authors demonstrate a digital navigation protocol for ESF maps in the context of hydrogen-bonded organic frameworks constructed from triptycene- and spiro-biphenyl-based molecular building blocks.