UC Berkeley

In this thesis, I investigate nanoporous materials such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) for various gas adsorption applications using a wide array of computational methods. These types of materials are ideal for gas adsorption and separation applications due to their large internal surface areas and tunable chemistry. They are also ideally suited to study using traditional computational methods due to their well-defined structures. In the first chapter, I introduce nanoporous materials and the various molecular mechanics methods which can be used to study them. I also introduce the topic of in silico materials design. Then, in the next chapter, I discuss the development of a DFT-derived force field to accurately study the gas adsorption behavior in materials which contain coordinatively unsaturated metal sites. In such materials, the most commonly used methods fail to accurately model adsorption behavior, and the introduction of the DFT-derived force field has allowed the study of flue-gas mixtures in these frameworks. Following this work, in the third chapter we discuss the use of the DFT-derived force field to study the dynamical behavior of greenhouse gases in the same MOF series. Much of this work was done in collaboration with experimentalists who used NMR as their primary tool to probe the dynamics of these gases in the materials. Our molecular dynamics simulations complemented their NMR experiments. In the fourth chapter, I switch gears and discuss the use of computational methods for the design of new materials, first to characterize experimentally synthesized materials, and then to construct a database of thousands of new COF structures. Finally, I conclude by sharing a summary of my findings from the various investigations discussed in this thesis and my future outlook for the field.