Computational Methods Based on Density Functional Theory for Reactions and Processes Involving Electronic Spin

Chemical processes and material properties often involve the molecular electronic spin. Many are crucial for energy applications such as catalytic processes involving d-block elements, or the properties of nanoparticles used to increase the rate of oxygen reduction to water in fuel cells. To understand the properties of these types of systems, first-principles computer simulations play a key role as tools to predict new phenomena, determine the material's parameters needed for modeling its behavior, and, more generally, analyze experimental results. This proposal aims to continue developing and testing the computational tools for electronic structure calculations for problems that fulfill the mission of the DoE. In particular, it expands the applicability of density functional theory (DFT) methods for magnetic systems, with particular emphasis in transition metal complexes. The proposed work focuses on two main thrusts: The first thrust is to adapt the driven Liouville-von-Neuman (DLvN) method for electron transport calculations to the realm of time-dependent density functional theory (TD-DFT). This thrust tackles the important problem of modeling molecular electronics (and spintronics). The second trust focuses on developing methodology to extract effective spin Hamiltonian parameters (magnetic exchange couplings) from DFT in a fast and reliable manner with practical applications in mind.