Discovery of hypothetical hetero-interpenetrated MOFs with arbitrarily dissimilar topologies and unit cell shapes

Abstract

Interpenetration is a commonly observed phenomenon in metal organic frameworks (MOFs) where multiple frameworks are entangled with each other. Hetero-interpenetration, where two (or more) distinct frameworks entangle with one another, is much rarer, although several cases have been observed in recent years. Interpenetration of either kind (hetero or homo) greatly affects the pore characteristics (size, shape, environment, dimensionality) and consequently the functionality/performance of the material. Given their complex nature, designing interpenetrated MOFs, particularly hetero-interpenetrated ones, is challenging. In this study, a novel computational method is described (and its source code shared) that can rapidly discover pairs of MOFs that may have distinct network topologies and unit cell shapes. By applying this method to search through a library of just over 6000 MOFs corresponding to 4.3 million MOF pairs, we were able to identify 18 hypothetical hetero-interpenetrated MOFs (whose crystals structures we provide).