Title: Ab initio Force Field for Metal Organic Frameworks Gas Adsorption Problems / Implementation of Density Functional Embedding Theory with PAW

Abstract:
This talk contains two parts, involving some recent developments on the classical simulation and the electronic structure techniques for solid materials, respectively. We will mainly focus on the first part, which presents a systematic method to develop classical potentials for metal organic frameworks (MOFs). MOF is a family of nanoporous material that has wide range of applications in gas adsorption and separation processes. It features great flexibilities in organic linker structures and spatial topologies. Therefore, computer simulation plays an important role in helping design or high throughput screening MOF structures. However, the fidelity of the empirical force field describing the interactions between MOFs and gas molecules is always under question. We introduce a systematic methodology to obtain force field parameters from symmetry adapted perturbation theory (SAPT) without any experimental inputs. In combination with specially designed simulation techniques, the new force field exhibits extraordinary robustness and transferability in simulations and demonstrates great power in studying MOF/gas systems. The second part goes into the electronic structure field and presents a new development in embedding theory for extended system. A new real-space projection algorithm was developed to enable optimize effective potential (OEP) calculations in combination with PAW formalism. Based on this algorithm, we are able to perform density function embedding calculations at all-electron level of theory, which shows promising potential in studying point defect states for semiconductor systems.
 
Biography:
Dr. Kuang Yu was an undergraduate student in the chemistry department, Peking University, supervised by Professor Yun-Dong Wu. Then he moved to the University of Wisconsin, Madison in 2008, where he obtained his Ph.D degree, supervised by Professor JR Schmidt. During this time, his work involves heterogeneous catalysis and force field developments for weak nonbonding interactions. Since 2013, he works in Professor Emily Carter’s group as a postdoc researcher in the mechanical & aerospace engineering department, Princeton University. Currently, his research interests are embedding theory development and first-principles studies on thin film solar cell systems.