Pr. Peter Gill, from the Australian National University, Canberra, Australia, is visiting the LCPQ during October 2019.

Peter Gill was born in Auckland, New Zealand in 1962. He received his B.Sc. and M.Sc. degrees from the University of Auckland, studying chemistry, physics and mathematics. He obtained his Ph.D. in 1988, working with Leo Radom at the Australian National University (ANU). Following postdoctoral work with John Pople and academic positions at Massey University, the University of Cambridge and the University of Nottingham, he returned in 2004 to ANU where he is currently the Professor of Theoretical Quantum Chemistry.

Pr. Gill is visiting the LCPQ thanks to a NEXT grant. **In collaboration with Pierre-François Loos he will conduct the following project.** The electronic Schrödinger equation is the starting point for a first-principles understanding of the behaviour of electrons and, thence, of chemical structure, bonding and reactivity. Indeed, the past 80 years have provided overwhelming evidence that, as Dirac observed in the early days of the quantum mechanical revolution, “the underlying physical laws necessary for the mathematical theory of a large part of physics and the whole of chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble.” The discipline of Quantum Chemistry seeks to devise and apply methods for solving those “much too complicated” equations as accurately and efficiently as possible.

Contemporary quantum chemistry has developed in two directions – wave function-based models and density-based models. Our group and others have recently made progress toward unifying these two approaches, using the accurate and rigorous methods of wave function theory to develop radical generalisations of density functional theory (DFT), which are free of the well-known limitations of conventional DFT. We have turned from infinite uniform electron gases to finite ones and this led to the development of the gLDA1 functional. By combining information about the electron density (in the style of DFT) and the curvature of the electron-electron hole (in the style of explicitly correlated wave function methods) at each point in space, the gLDA1 functional delivers chemical predictions which are roughly an order of magnitude more accurate than the conventional LDA functional on which it was based. This is encouraging but, by construction, gLDA1 is applicable only to one-dimensional (1D) molecules. This research project seeks to construct the gLDA2 functional for 2D and 3D systems. These functionals will constitute an important milestone in the development of modern DFT.

Please visit Peter Gill’s webpage to find out more about his research.