Marcel Swart: Quantum-chemistry approaches for molecules and materials

Understanding and predicting reactivity and spectroscopy is at the heart of research in the fields of chemistry, biology and physics and ultimately materials. Quantum mechanics plays a major role here, including the atomic and/or molecular properties that can be derived from it for use in molecular modeling techniques. I will outline four main lines of research that are intertwined and reinforce each other: (i) development of new quantum-mechanical methods; (ii) development of molecular modeling techniques based on a physically correct ansatz for parameter determination; (ii) new approaches for accurate and efficient structure optimization, transition-state searches and molecular simulation techniques; (iv) direct application of quantum mechanics for reactivity, transition-metal chemistry and nanostructures. Applications where these four approaches have been used include the complete reactivity of fullerenes, polarization effects in nanostructures, and examples of transition-metal chemistry. Moreover, the remarkable case of the intimate connection between transition-metal chemistry and bimolecular substitution reactions in organic chemistry has been explored.

The key challenge however is to improve both the currently available quantum-mechanical methods and the molecular modeling techniques. This means both the design of new density functional approximations, and the correct parameterization of molecular modeling techniques for (transition-)metals. Directly obtaining these parameters from quantum-mechanics seems to be viable for any atom now (metal or non-metal). These new approaches open up a new computational vision of molecules and materials, which can be used for characterization, understanding and predictions.