Research Guides

Department of Chemistry University of Oxford

Professor Stuart Mackenzie

Our research is characterised by the development of novel optical spectroscopy techniques to provide new insights into important scientific problems ranging from fundamental interactions in catalysis to magnetosensing in animals. We work in both the gas phase (in molecular / cluster beams) and the condensed phase and  all our work involves healthy mixture of experiment and theory / computation. Much of the group's research is highly interdisciplinary and we have successful collaborations with several other internationally-leading research groups both within the UK and overseas. For more details on the group activities, along with opportunities to join please see the research group website which includes a full list of group publications.

I. Structure and reactivity of small gas-phase metal and metal-ligand clusters

Small clusters of atoms – particularly those of transition metal atoms – exhibit many remarkable size-dependent physical properties which can be quite unlike those of either isolated atoms or the bulk metal.  Understanding the evolution of these properties with cluster size and composition is key to understanding nanoparticle chemistry. In particular, little is known of the complex and subtle relationship between structure - both electronic and geometrical - and reactivity towards small molecules. We employ a diverse range of experimental techiniques including infrared photodissociation and velocity map imaging to probe key interactions as a function of cluster size and isomeric form.

 

 


 II. Optical cavity-based spectroscopy in the condensed phase

Cavity-based optical techniques such as cavity ring-down and cavity enhanced absorption spectroscopy have revolutionised sensitive gas-phase trace detection. Extension  to the condensed phase has been comparatively slow but we have developed a range of condensed phase variants of both techniques in order to study dynamical photochemical and interfacial phenomena.

In particular, we collaborate with Professors Peter Hore and Chris Timmel in applying these sensitive detection methods to the study of the dynamics of photo-generated spin-correlated radical pairs within blue-light receptor proteins called cryptochromes. It is believed that such dynamics, and in particular their sensitivity to external magnetic fields, may lie at the heart of the ability of many animals to sense the Earth's magnetic field.

Gas-phase clusters

IR Signature of Size–Selective CO2 Activation on Small Platinum Cluster Anions, Ptn (n = 4–7)
Angew. Chemie - Int Ed., 57, 14822 (2018)

Time resolved inner-shell photoelectron spectroscopy of UV-induced photodissociation of CH3I
Phys. Rev. A, 97, 043429 (2018)

Infrared spectroscopy of Au+(CH4)n complexes and vibrationally-enhanced C-H activation reactions
Top. Catal., (2018) 61, 81, (2018)

Infrared signature of structural isomers of gas-phase M+(N2O)n (M = Cu, Ag, Au) ion-molecule complexes
J. Phys. Chem. A, 121, 7565 (2017)

Photofragmentation dynamics and dissociation energies of MoO and CrO
J. Chem. Phys. 147, 013921 (2017)

Infrared spectroscopy of gas-phase M+(CO2)n (M = Co, Rh, Ir) ion-molecule complexes
J. Phys. Chem. A, 121, 133 (2017)

 

Magnetic Field Effects / Cavity-based spectroscopy

Magnetically sensitive radical photochemistry of non-natural flavoproteins
J. Am. Chem. Soc., 140, 8705, 2018

Millitesla magnetic field effects on the photocycle of an animal cryptochrome
Nature Sci. Rep. 7, 42228, 2017

Engineering an artificial flavoprotein magnetosensor
J. Am. Chem. Soc., 138, 16584, 2016

Sub-milllitesla magnetic field effects on the recombination reaction of Flavin and ascorbic acid radicals
J. Chem. Phys, 145, 085101, 2016

Chemical amplification of magnetic field effects on radical pair reactions relevant to avian magnetoreception
Nature Chemistry, 8, 384, 2016