Our central field of research is Theoretical and Computational Chemistry, in particular Quantum Chemistry. Currently we focus on theoretical developments in Quantum Chemistry, especially in Valence Bond Theory. The applications range from modeling of chemical reactivity for small systems to enzymatic reactions.
Ab intio Valence Bond Methods
Molecular orbital (MO) theory undoubtedly dominates contemporary quantum chemistry. Nevertheless, valence bond (VB) theory remains as a widespread conceptual matrix for many chemists. The bottleneck for efficient developments in ab initio VB theory is the use of non-orthogonal orbitals that results in enormous computational effort. To convert VB theory into a mainstream method in contemporary quantum chemistry, one needs to develop practical VB methods with satisfactory accuracy. As a long-term goal of our research, we focus on theoretical developments in valence bond theory at various levels and their program implementation.
Muiti-reference Based Density Functional Theory
Density functional theory (DFT) within the Kohn-Sham scheme is undoubtedly the most powerful tool for electronic structure calculations in atomic, molecular and solid-state systems. However, it still surfers from several difficulties. One of the dramatic failures is in strongly correlated systems, which share strong multi-reference character. We are interested in finding solutions to this problem, particularly by using valence bond theory, which is a multi-determinants based approach.
Metallo-enzymes like Cytochrome P450 carry out essential life sustaining reactions such as oxygen capture, oxygen binding, oxidation of organic material to metabolically important species and as means of neutralizing toxic compounds. The field is full of exciting problems.
Deep understanding of intermolecular interactions within an ab initio framework in various environments is greatly helpful for molecular energy, structure, and properties . With quantum mechanics methods, the energy decomposition analysis (EDA) scheme divides the total interaction energy into several individual terms to provide physical insights of intermolecular interactions. We focus on theoretical developments and applications of EDA methods to explore the nature of various kinds of intermolecular interactions.