Laser

News & Events

Fred Cascarini completes his PhD

Congratulations to Fred Cascarini for completion of his PhD following his viva voce examination in September 2020.  Fred’s thesis research involved the experimental study of collisional and photodissociation dynamics in the gas phase using velocity map imaging methods, and the theoretical simulation of chemical reaction dynamics.  He now plans a legal career and will be starting a law conversion course.

Victoria Taylor completes her PhD

Many congratulations to Victoria Taylor who had her viva voce examination in July 2020 and successfully completed her PhD.  Victoria’s thesis describes the use of ultrafast laser spectroscopy and construction of a transient absorption microscope in Tom’s lab to study photo-responsive materials such as perovskites and hybrid J-aggregate gold nanoparticles. She will take up a post-doc position with Ralph Ernstorfer at the Fritz Haber Institute of the Max Planck Society Berlin in September.

Marta Duchi completes her PhD

Congratulations to Marta Duchi who completed her PhD in July 2020 and was the first group member to have a viva voce examination on Zoom.  Marta’s thesis work included the implementation of ultrafast two-dimensional electronic spectroscopy (2DES) in Tom’s lab.  She has now joined Prof Peter Hamm’s group at the University of Zurich as a postdoc.

Nature Chemistry paper on heterocylic ring-opening dynamics

A previous Bristol Laser Group study of the UV photoinduced ring-opening reaction of the heterocyclic molecule, 2(5H)-thiophenone in solution (available here) served to inspire an international team to undertake an ultrafast time-resolved pump-probe study of the reaction in vacuum at FERMI, the world’s first seeded free-electron laser (in Trieste). Following photoexcitation, the new study allows direct observation of the initial ring opening and non-adiabatic coupling to the electronic ground state within 350 fs, driven by ballistic S–C bond extension, and visualization of the subsequent ground-state dynamics – that involves formation of and interconversion between ring-opened isomers and the cyclic structure and fragmentation over much longer timescales.  The paper is ‘Tracking the ultraviolet-induced photochemistry of thiophenone during and after ultrafast ring opening’ by S. Pathak, …. , C.S. Hansen, R.A. Ingle, M.N.R. Ashfold, et al., published in Nature Chemistry and featured on the cover, with further details here.

Tom Oliver’s Royal Society University Research Fellowship Renewed

Tom’s prestigious Royal Society University Research Fellowship has been renewed for a further 3 years. Tom was originally awarded his fellowship in 2015. In 2018 he was made the offer of a proleptic lectureship at Bristol, and in 2019 promoted to Associate Professor.

New papers in JACS and Chemical Science

Congratulations to Ryan Phelps, and to Luke Lewis-Borrell and coauthors for recent papers in the Journal of the American Chemical Society and Chemical Science.  Both papers report transient ultrafast spectroscopy of reactive intermediates.  Ryan’s work describes studies of the mechanisms and kinetics of carbene reactions with organic solvents to form ylides and enols (Direct observation of ylide and enol intermediates formed in competition with Wolff rearrangement of photo-excited ethyl diazoacetoacetate, R. Phelps and A.J. Orr-Ewing, J. Am. Chem. Soc. 2020, 142, 7836; DOI 10.1021/jacs.0c00752).  Luke’s paper shows how multiple sequential steps in a photoredox catalysed cycle can be tracked by transient IR absorption spectroscopy (Mapping the multi-step mechanism of a photoredox catalysed atom-transfer radical polymerization reaction by direct observation of the reactive intermediates, L. Lewis-Borrell, A. Bhattacherjee, M. Sneha, et al., Chemical Science 2020, 11, 4475; DOI 10.1039/D0SC01194K).

Nature Comms paper is an Editors’ Highlight

The recent paper ‘Ultraviolet photolysis of H2S and its implications for SH radical production in the interstellar medium’ (Nat. Comm. 11, 1547 (2020)) describing collaborative work by Mike Ashfold, Colin Western, ex-group member Chris Hansen (now at UNSW in Sydney) and colleagues at the Dalian Coherent Light Source has been selected to feature in a Nature Communications Editors’ Highlights webpage.

Poster Prize for Georgia Thornton

Congratulations to Georgia Thornton for winning a poster prize at the annual RSC Spectroscopy and Dynamics Group Conference, held at the University of Warwick from 6 – 8 January 2020.  Georgia’s poster entitled “Studying the Electron Transfer Driven Polymerisation of N-ethylcarbazole using Transient Absorption Spectroscopy” describes her work studying reaction mechanisms in solution using ultrafast spectroscopy.

Giordano represents Bristol at the 6th Jilin University Chemistry Graduate Forum

Giordano Amoruso, Mary Jenkinson-Finch (Steve Mann’s group) and Roman Abrams (Jonathan Clayden’s group) were the University of Bristol’s representatives at the 6th Jilin University Chemistry Graduate Forum. Giordano presented his recent work investigating Förster resonant energy transfer in quantum dot-bacterial reaction centre conjugates.

Chris Hansen wins ARC Discovery Early Career Researcher Award

Congratulations to former group member Dr Chris Hansen who has won an Australian Research Council DECRA Fellowship to launch his independent research into the impact of fluorinated compounds in the atmosphere.  Chris will be leading this research project at the University of New South Wales in Sydney.

Matt Bain finishes his PhD

Congratulations to Matt Bain for a successful defense of his PhD thesis in his viva on 4/11/2019.  Matt’s doctoral research involved development and application of new photoionization and multi-mass velocity map imaging methods to study photochemical dynamics and product branching ratios.  He is now a postdoctoral research fellow with Prof Steve Bradforth at the University of Southern California.

Ed Mahoney completes his PhD

Congratulations to Ed Mahoney for success in his PhD viva.  Ed’s thesis explores alternative excitation mechanisms in microwave activated plasmas operating under conditions relevant to the chemical vapour deposition (CVD) of diamond.  Ed is spending a few more months in Bristol as a PDRA working on an impact acceleration project to improve the atom efficiency of diamond CVD, but plans to be travelling in South East Asia before the end of 2019.  

Welcome to Daniel Polak

Dr Daniel Polak joins the Bristol group following PhD studies with Dr Jenny Clark at the University of Sheffield. In his PhD, Daniel studied singlet fission of polyenes inside de novo maquette proteins and the effect of microcavities on the emission efficiency of singlet fission. Daniel will use multidimensional optical spectroscopies to explore chemical and biomolecular condensed phase dynamics.

Poster Prize for Aditi Bhattacherjee

Congratulations to Aditi Bhattacherjee who won a poster prize at the 14th Femtochemistry Conference (FEMTO 14) in Shanghai (July 28 – Aug 2 2019).   Her poster, “Tracking a Photocatalytic Decarboxylation Reaction over Picosecond to Millisecond Timescales using Ultrafast Infrared Transient Absorption Spectroscopy” described some of the Bristol group’s recent studies of the mechanisms of photoredox catalysed organic reactions using transient infra-red absorption spectroscopy.

Special Issue of PCCP marks Mike Ashfold’s 65th birthday

To celebrate Mike Ashfold’s sixty-fifth birthday, Andrew Orr-Ewing has guest edited a special issue of Physical Chemistry Chemical Physics themed on Photodissociation and Reaction Dynamics to coincide with Mike’s birthday. The volume contains 59 peer-reviewed articles from Mike’s friends, colleagues and collaborators from across the world, including contributions from current Bristol colleagues Carmen Galan, Tom Oliver, Andrew Orr-Ewing, Dudley Shallcross, Colin Western, and Bristol alumni Basile Curchod, Jeremy Harvey, Craig Murray and David Tew.

Three project students win prizes

Congratulations to Joe McManus, Becky Martin and Ben Carwithen who all won School of Chemistry prizes for their achievements in the final year of their degree programmes.  Joe (left) was awarded the Physical and Theoretical Chemistry Project Prize and received a Head of School Commendation Letter.  Becky (centre) received the Peter Cox Prize and a Head of School Commendation Letter.  Ben (right) was awarded the Richard Dixon Prize.

Faraday Discussion 217 on Ultrafast Photoinduced Energy and Charge Transfer, Ventura, CA, Apr 8-10, 2019

The Scientific Committee for Faraday Discussion 217, the first ever to be held in California, comprised Mike Ashfold and recent Benjamin Meaker Fellow Steve Bradforth (Univ. S. California), Tom Oliver, Jennifer Ogilvie (Michigan), Naomi Ginsberg (U.C. Berkeley) and Vas Stavros (Warwick). The Discussion, which was very well attended, featured Introductory and Closing Remarks lectures by, respectively, Majed Chergui (EPFL) and Bern Kohler (Ohio State), 23 other papers for discussion and about 60 posters (including one from group member Marta Duchi, who is pictured with Mike on the beach in Malibu).

Andrew Orr-Ewing delivers the 2019 Burton Lecture at King’s College London

Andrew was invited to give the 2019 Burton Lecture at King’s College London on 20 March, and spoke about his research group’s work on the use of transient absorption spectroscopy to study photochemical reaction mechanisms.  Professor Harold Burton was Head of the Department of Chemistry from 1947 until 1966, and the series of annual lectures to commemorate his contributions began in 1970.

Poster Prize for Luke Lewis-Borrell

Congratulations to Luke Lewis-Borrell who won a poster prize at the SCI Spotlight on Photoredox Catalysis and Photochemistry meeting in London on 26th Feb.  Luke’s poster highlighted how ultrafast transient absorption spectroscopy methods can be used to characterize the excited state lifetimes and electron transfer rates of organic molecules designed for use as photoredox catalysts, and hence how photoredox-catalysed reaction mechanisms can be unravelled.  The work will lead to new design principles for future generations of catalysts.