Targeted design of porous materials without strong, directional interactions

A porous molecular crystal (TSCl) was found to crystallize from solution during the synthesis of tetrakis(4-sulfophenylmethane) from dichloromethane and water. Crystal structure prediction (CSP) allowed us to understand the driving force behind the formation of this porous TSCl phase and the intermolecular interactions that drive its formation. Gas sorption analysis showed that TSCl is permanently porous with selective adsorption of CO2 over N2, H2 and CH4 and a maximum CO2 uptake of 74 cm3/g at 195 K. Calculations revealed that TSCl assembles via a combination of weak hydrogen bonds and strong dispersive interactions. This illustrates that CSP can underpin new approaches to crystal engineering that do not involve more classical directional interactions, such as hydrogen bonding