Computational and Theoretical Quantum Chemistry

Our research interests are focused in three main areas:

1. Fundamental quantum chemical physics: exploring the fundamental interactions in three-body Coulomb systems. We use a novel series solution methodology to calculate highly accurate energies and wavefunctions that can be used to address fundamental chemical physical questions such as the emergence of molecular structure and the conditions for bound state stability.

2. Computation chemistry research: involving extensive collaboration with experimental chemists. This research provides essential insight into the structure, reactivity and spectroscopy of molecular complexes and also guides (gas phase) experimental design. We use a variety of techniques including density functional theory (DFT and TDDFT) and ab initio methods. Current projects involve:

  • Evaluating the influence of relativistic effects on the chemical bond and response properties such as NMR and electronic excitations
  • The optimisation of minima and transition state structures in elementary reaction steps of inorganic/organometallic complex bond activation and catalysis
  • Studying the structure, reactivity and spectroscopy of metal-ligand complexes.

3. Theoretical chemistry research: highlighting and addressing fundamental limitations in theoretical methods. Current projects involve the inadequacy of adiabatic time-dependent density functional theory (TDDFT) for some open-shell complexes. 

Recent highlights include:

  • Determining the success and limitation of Time-Dependent Density Functional Theory (TDDFT) when applied to some open- and closed-shell metal ligand complexes
  • Zn(I) superoxide formation in the gas phase: providing quantitative interpretation
  • Identification of what makes a good ligand in terms of its ability to stabilise a metal cation (curve-crossing processes)
  • Preferential solvation of metal dications in gas phase mixed-solvent systems: how competing interactions are dominated by differences in molecular properties
  • Understanding the anomalous acidity of Pb2+, Sn2+, and Hg2+
  • Predicting the lower bound to stability of unit charge Coulomb three-body systems
  • Correlating the minimum relative excess energy due to the presence of a third particle in symmetric three-body systems with the transition point from atomic- to molecular-type density distributions