Remote substituent effects on catalytic activity of metal-organic frameworks: a linker orbital energy model

Abstract

The Hammett equation is commonly used to theoretically depict the remote electronic effects of substituents on catalytic activities of metal nodes of metal-organic frameworks (MOFs). However, the application of the theory to MOF catalysts usually encounters problems because it relies heavily on empirical parameters with unknown transferability. To develop an alternative prediction theory, the linker orbital energy model has been proposed by density functional theory calculations. The model provides a simple method to approximately depict the remote electronic substituent effects on catalytic activities of metal nodes of MOFs, and its general applicability to MOFs is supported by extensively revisiting the structure-activity relationships reported in the literatures. The model can be used to design catalytic activity of metal nodes of MOFs by engineering the electronic properties of linkers and substituents.