Logic and symbolism of switchable porous framework materials

Abstract

Metal-organic frameworks (MOFs) are highly porous materials composed of organic linkers and inorganic nodes. A subset of MOFs can switch between at least two structures differing significantly in porosity, offering new opportunities for application technologies. However, network topology, micromechanics of building blocks and their hinges, particle size, defects, agglomeration etc., are convoluted into the responsiveness of the system. Many factors are a consequence of the material’s history, including synthesis, desolvation, and all subsequent handling steps, leading to a complex interplay of factors difficult to express clearly by ordinary language systems, chemical or mathematical symbols without loss of intuitive understanding. Here, we propose a symbolic language for the rationalization of switchability emphasizing the history-dependent responsivity of many dynamic frameworks and their stimuli-induced phase transitions. The system follows a bivalent logic inspired by Freges “Begriffsschrift”, providing a fundamental logic structure for the rationalization of statements and representation of logic gates. Switchability of metal-organic frameworks is influenced by the complex interplay of factors that are difficult to retrace. Here, a symbolic language of switchability is proposed, providing a fundamental logic structure for the rationalization of statements and representation of logic gates.