A General Approach for Estimating Framework Charges in Metal-Organic Frameworks

Although the number of metal-organic frameworks (MOFs) is nearly Infinite, the atom types included are quite limited. On the basis of this thought, this work provides it strategy for estimating framework charges in MOFs. We developed a so-called connectivity-based atom contribution method (CBAC), in which it is assumed that the atoms with same bonding connectivity have identical charges in different MOFs. The results for 43 MOFs including a training set of 30 MOFs and a test set of 13 MOFs show that the CBAC charges give nearly identical results to those from quantum mechanical calculations for adsorption Isotherms of CO2, CO, and N-2 in them. Since the method will readily include new atom types, it is applicable to any MOF as long as its structure is known. The strategy, which is applicable to Other porous materials, paves it way for large-scale computational screening of MOFs for specific applications its well as contributes to it better Understanding of the structure-property relationships for MOFs and eventually contributes to the development and application of MOFs.