Gustavo Scuseria of Rice University is supported by an award from the Chemical Theory, Models and Computational Methods program for research to develop accurate approaches for describing strong (also known as static or non-dynamical) correlations in electronic structure theory. More than eighty years after the formulation of Schrodinger's equation, computational quantum chemistry has matured considerably, yet there remain formidable challenges to describing the electronic structure of many molecules and solids. When near or exact degeneracies are present, the single determinant picture breaks down and a description of strong correlation due to these degeneracies becomes crucial for even a qualitative description of the electronic structure. Addressing emergent electronic phenomena in chemistry, biology, and materials science requires calculations with significantly large active spaces, necessitating the development of alternative, more efficient descriptions of static correlation.
The focus of this proposal is a method known as Constrained-Pairing Mean-Field Theory or CPMFT. The work is expected to significantly enhance our ability to model from first-principles the behavior of electrons in molecules and solids, resulting in better understanding and prediction of materials properties and chemical reactions. Many of the tools developed in the PI's group are widely used in academia, national laboratories, and industry. The current work is expected to have an equally broad impact and to contribute to the training of students at all levels.