Reticular Chemistry and Harvesting Water from Desert Air

ALTHOUGH CHEMISTS IN general are concerned with the art and science of constructing molecules and understanding their behavior, for a long time the idea that such molecules can be linked together by strong bonds to make infinite, extended structures was fraught with failure. The notion of using molecular building blocks to make such structures invariably led to chaotic, ill-defined materials and therefore not only defying the chemists’ need to exert their will on the design of matter but also preventing them from deciphering the atomic arrangement of such products. The field remained undeveloped for most of the twentieth century, and it was taken as an article of faith that linking molecules by strong bonds to make extended structures is a “waste of time” because “it doesn’t work.” This state of affairs was changed when a little known contribution was published 1994, where it was shown that negatively charged germanium sulfide clusters can be linked by positively charged manganese ions to make an extended structure (Figure 1).1 This was the first successful demonstration of linking molecular building blocks by strong bonds to make solid-state materials. The fact that the product was made in crystalline form and that the original clusters were translated into the crystal had two immediate ramifications: The crystallinity led to atomic level identification of the resulting structure while the preservation of the cluster geometry meant that in future the ability to predict accurately the outcome of such syntheses might become real especially since the cluster units are directional. There were additional advantages which became central to this emerging field. For example, the cluster constituents and their linkage (strong metal-sulfide bonds) provided the potential for making robust structures, and in the present case these Omar Yaghi Omar M. Yaghi obtained his Ph.D. from the University of Illinois-Urbana and was an NSF Postdoctoral Fellow at Harvard University. He currently holds the James and Neeltje Tretter Chair Professor of Chemistry at the University of California, Berkeley. He is the Founding Director of the Berkeley Global Science Institute and the Co-Director of the Kavli Energy NanoScience Institute. He is known for establishing reticular chemistry and developing new classes of porous, crystalline solids, termed metal-organic frameworks and covalent organic frameworks. He has been recognized by awards from fifteen countries, including the Wolf Prize in Chemistry (2018), U. S. National Academy of Sciences (2019), and the Royal Society of Chemistry Sustainable Water Award (2020). Although chemists in general are concerned with the art and science of constructing molecules and understanding their behavior, for a long time the idea that such molecules can be linked together by strong bonds to make infinite, extended structures was fraught with failure. The notion of using molecular building blocks to make such structures invariably led to chaotic, ill-defined materials and therefore not only defying the chemists’ need to exert their will on the design of matter but also preventing them from deciphering the atomic arrangement of such products. The field remained undeveloped for most of the twentieth century, and it was taken as an article of faith that linking molecules by strong bonds to make extended structures is a “waste of time” because “it doesn’t work.” by Cheng-Hsin Liu, Ha L. Nguyen, and Omar M. Yaghi https://doi.org/10.51167/acm00007 Cheng-Hsin Liu Cheng-Hsin Liu is pursuing a B.S. in Chemical and Biomolecular Engineering at the University of California, Berkeley. He is currently working with Professor Omar M. Yaghi on the structure modeling and characterization of reticular structures for carbon capture and other clean energy applications.