Current Research
I am Emeritus Professor with the School of Physics & Astronomy at the University of Nottingham. My research interests are in the field of quantum molecular dynamics. I investigate molecular tunnelling and other quantum phenomena using specialised field-cycling NMR techniques and inelastic neutron scattering. I have longstanding expertise in the study of quantum tunnelling in methyl (CH3) groups and hydrogen bonds. Here, I study the influence of the wave-like properties of matter on the dynamics of atoms and molecules as they navigate the multi-dimensional potential energy surface that arises from the electrostatic interactions with the molecular environment. These quantum effects are revealed at low temperature, typically 4K. In recent years I have specialised in studying endofullerenes, wherein small molecules such as H2 (hydrogen molecule) and H2O (water) are confined inside the cage of a C60 fullerene molecule. These are highly quantum systems, with all translational and rotational degrees of freedom being quantised. In this context, the coupling of translational and rotational angular momenta also reveals interesting effects.
An important quantum mechanical characteristic of symmetrical molecular rotors such as H2, H2O and CH3 lies in the phenomenon of nuclear spin isomerism. Arising from the entanglement of spatial and nuclear spin degrees of freedom and the Pauli Exclusion Principle, we can identify discrete nuclear spin-symmetry species. This purely quantum mechanical effect has no analogue in classical mechanics and gives rise to interesting and novel nuclear spin polarisation effects, including dynamic nuclear polarisation (DNP). I have investigated the fundamental physics underpinning this area of quantum dynamics to study novel schemes for nuclear spin hyperpolarisation.
The pervasive influence of nuclear spin on the dynamics of atoms and molecules leads us to employ experimental techniques that are receptive to spin. In nuclear magnetic resonance (NMR) we have found it is important to exploit the full range of magnetic field, so we have developed highly specialised magnetic field-cycling NMR spectrometers for our studies. Inelastic neutron scattering experiments provide an important complementary technique to those of magnetic resonance. These experiments are conducted at the Institut Laue-Langevin in Grenoble, France and at the ISIS facility housed within the Rutherford Appleton Laboratory in Oxfordshire, UK.
Scopus Author ID: 6701847755
Orchid profile: http://orcid.org/0000-0002-8086-1374