Research Fellows Directory
Dr Andrew Teale
University of Nottingham
Our research focuses on the development of new density-functional theory approaches. Density-functional theory is now the most widely applied electronic structure method in chemistry and physics. It uses the electronic density as the central variable and has been applied to calculate the energies and properties of materials ranging in size from a few atoms through to tens of thousands of atoms and infinite periodic crystal lattices.
The computational efficiency of the approach and its ability to deliver reasonable accuracy for systems covering a broad range of sizes has lead to its widespread adoption. However, the accuracy of the method depends critically on terms in the electronic energy that describe the quantum mechanical exchange and correlation interactions of the electrons with each other. Furthermore, almost all present day implementations use the Kohn--Sham approach to density-functional theory in which the electronic system is described by a density arising from a single Slater determinant.
Many of the errors associated with density-functional calculations can be attributed to the approximate exchange-correlation functionals employed. However, others such as the failure to treat the energetics of bond making and breaking processes reliably (which are central to chemistry), or the treatment of molecules in the presence of magnetic fields, require more fundamental extensions of the underlying theory. Our research focusses on the implementation and testing of these extensions for chemical applications. These beyond-Kohn-Sham approaches are expected to lead to significantly better descriptions of mechanistic and photochemistry as well as magnetic properties of spectroscopic importance in chemistry. This in turn has the potential to have a significant impact on the size and types of materials that may be studied in a reliable manner using density-functional based approaches.
Interests and expertise (Subject groups)