Temperature, Concentration, and Stoichiometry Effects on the Self-Assembly Mechanisms of Cubic-Symmetry MOFs: A Multiscale Simulation Study

The formation mechanisms of metal-organic frameworks (MOFs) are not fully understood, which hinders the synthesis of new structures due to uncertainty in conditions that allow nodes and linkers to self-assemble. While node-linker coordination strength is known to strongly influence assembly pathways and the formation of intermediate amorphous clusters, the effects of temperature, linker concentration, and metal-to-linker stoichiometry remain unclear. Understanding these factors is essential to dissect the kinetic and thermodynamic contributions to self-assembly.

 

We employ a multiscale simulation strategy combining density functional theory (DFT), metadynamics, standard molecular dynamics (MD), and Hamiltonian replica exchange (HREX) with a coarse-grained (CG) model to investigate how these variables affect MOF assembly. By sampling free energy landscapes, we examine minimum energy pathways for cluster formation and reorganization, assessing the influence of kinetic barriers and thermodynamic stability. This framework provides insight into how environmental and compositional factors shape assembly pathways and intermediate states, informing experimental strategies to favor the formation of ordered cubic frameworks and control crystal size and order.