2, Oregon State University, Corvallis, Oregon, United States
Metal-Organic-Frameworks (MOFs) are molecular latticework structures composed of organic linking molecules (linkers) bonded with inorganic nodal unites (nodes). We recently developed a computer algorithm that uses grammatical evolution to design, without human supervision, MOFs with kinematically active linkers. In this work we dissect the folding mechanisms employed by the most successful MOFs that the computer designed. Large scale molecular dynamics simulations were performed of MOFs collapsing under pressure and cooperative patterns of linker folding and node rotation identified. By analyzing the patterns of folding we assess the diversity of kinematic strategies that the computer algorithm discovered. We comment on the applicability of this approach to the design of other mechanically active polymers.
Acknowledgments: The authors acknowledge the support of the W.M. Keck Foundation and the National Science Foundation.