(527b) High Throughput Computational Screening of Porous Crystalline Materials

In the last decade, a wealth of novel porous crystalline materials have been synthesized by what has come to be called ?modular? or ?reticular chemistry?. This new approach, as opposed to serendipitous methods of the past, leverages the self-assembly of modular molecular ?building blocks? that can only assemble in very specific orientations and allows one to design an enormous number of new porous crystals, far beyond what can actually be synthesized in a reasonable amount of time. Using chemical intuition, various groups have identified crystals with remarkable properties, such as MOF-177, which can capture 4.5 times more CO2 at 35 bar than the next best material known previously (Millward and Yaghi, JACS 2005, 127, 17998). To fully capitalize on the promise of reticular chemistry for finding new and better materials, computational methods will be required due to the sheer number of possibilities. While computational investigations have been used to screen dozens of porous materials at a time (Yazaydin et al., JACS 2009, 131, 18198) or reveal useful relationships between gas adsorption behavior and geometric material properties (Frost, H.; Snurr, R. J. Phys. Chem. C 2007, 111, 18794), they have been limited in speed, by the need to apply quantum chemistry methods for at least part of the study, and in scope, by relying on crystal structures available in databases of finite size. In this work, we present a novel high throughput computational screening method for the rapid evaluation of gas adsorption properties of already synthesized, as well as hypothetical, porous crystalline materials. This method can be applied to search for optimal materials for gas uptake and/or gas separation applications, such as hydrogen storage or carbon dioxide separation from flue gases. As a demonstration of the approach, we apply this screening method to study a large number of existing and proposed materials, primarily metal-organic frameworks (MOFs), to identify a few promising candidates for carbon dioxide separation from flue gases.