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RSC Spectroscopy and Dynamics Group Meeting 2020

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RSC Spectroscopy and Dynamics Group Meeting 2020 RSC Spectroscopy and Dynamics Group Meeting 2020 University of Warwick 6th – 8th January 2020 We would like to extend our thanks to the RSC and all of our sponsors for their generous support of this year’s Spectroscopy and Dynamics Group meeting. Please show your support for our sponsors by visiting their trade stands during the coffee breaks and Tuesday’s poster session. Programme All presentation sessions will take place in Meeting Room 2 inside the Radcliffe Conference Centre. Monday 6th January 16:00 - 18:00 Arrival and Registration 18:00 - 19:00 Dinner Dining Room Session 1 Chair: Caroline Dessent 19:00 - 19:05 Welcome Vas Stavros (Warwick) 19:05 - 19:50 Invited tutorial talk Helen Fielding (UCL) 19:50 - 20:35 Invited tutorial talk Tom Penfold (Newcastle) 20:35 - 21:35 SDG AGM Meeting Room 2 Tuesday 7th January 07:00 - 08:30 Breakfast Dining Room* Session 2 Chair: Michael Staniforth 09:00 - 09:45 Invited talk David Osborn (Sandia NL) 09:45 - 10:05 Contributed talk David Kemp (Nottingham) 10:05 - 10:25 Contributed talk Klaudia Gawlas (UCL) 10:25 - 10:45 Contributed talk Preeti Manjari Mishra (RIKEN) 10:45 - 11:15 Tea/Coffee Lounge Session 3 Chair: Jutta Toscano 11:15 - 12:00 Invited talk Sonia Melandri (Bologna) 12:00 - 12:20 Contributed talk Maria Elena Castellani (Durham) 12:20 - 12:40 Contributed talk Javier S. Marti (Imperial) 12:40 - 13:00 Contributed talk Conor Rankine (Newcastle) 13:00 - 14:15 Lunch Dining Room Session 4 Chair: Nat das Neves Rodrigues 14:15 - 14:35 Contributed talk Jacob Berenbeim (York) 14:35 - 14:55 Contributed talk Thomas Wall (Imperial) 14:55 - 15:15 Contributed talk Ayse Duran (Nottingham) 15:15 - 15:35 Contributed talk David Heathcote (Oxford) 15:35 - 15:55 Contributed talk Jutta Toscano (Colorado) 16:00 - 16:30 Tea/Coffee Lounge 16:30 - 18:00 Poster session** and trade display 18:00 - 19:00 Invited Talk Bern Kohler (Ohio) 19:00 - 20:00 Conference Dinner Dining Room 20:30 - 22:00 Quiz Dining Room Wednesday 8th January 07:00 - 08:30 Breakfast Dining Room* Session 5 Chair: Javier Segarra-Marti 09:00 - 09:45 Invited talk Eric Vauthey (Geneva) 09:45 - 10:05 Contributed talk Alex Auty (Sheffield) 10:05 - 10:25 Contributed talk Mahima Sneha (Bristol) 10:25 - 10:45 Contributed talk Daniel Coxon (Warwick) 10:45 - 11:15 Tea/Coffee Lounge Session 6 Chair: Mahima Sneha 11:15 - 12:00 Invited talk Julia Lehman (Leeds) 12:00 - 12:20 Contributed talk Andriana Tsikritea (Oxford) 12:20 - 12:40 Contributed talk Lea Maria Ibele (Durham) 12:40 - 13:00 Contributed talk Lingfeng Ge (Bristol) 13:00 - 14:15 Lunch Dining Room Session 7 Chair: Stuart W. Crane 14:15 - 14:35 Contributed talk Emily Holt (Warwick) 14:35 - 14:55 Contributed talk Ecaterina Burevschi (KCL) 14:55 - 15:15 Contributed talk Matthew Rayment (UCL) 15:15 - 15:35 Contributed talk João Figueira Nunes (Lincoln) 15:35 - 15:55 Contributed talk Alice Green (Oxford) 15:55 - 16:30 Tea/Coffee Lounge 16:30 Finish *For attendees staying at accommodation sites other than Radcliffe (i.e. Scarman and Arden), breakfast will be served in their respective dining rooms. All other meals will be served at Radcliffe for all attendees. **Posters can be put up from 4pm on Monday (first conference day) but must be taken down by 9am on Wednesday (last conference day). Talk Abstracts University of Warwick 6th – 8th January 2020 Invited Tutorial Talk Liquid-microjet UV photoelectron spectroscopy Helen H. Fielding1,* 1 Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K. * [email protected] In nature, light drives many important processes such as photosynthesis and vision. Light-driven processes are also important in technology, such as in nanoscale electronic devices. At the heart of all these processes are small chromophores that absorb light and, subsequently, undergo small- scale structural changes. Understanding the fundamental photophysics and photochemistry of the chromophores that determine the efficiency of light-driven processes in nature and technology is crucial for the rational design of new photomaterials for a range of applications such as photovoltaics and bioimaging. In addition to a detailed knowledge of the intrinsic electronic structures of these chromophores, it is important to have an understanding of the roles of their environments. Experimentally, the most direct way of probing electronic structure is through the measurement of electron binding energies using photoelectron spectroscopy (PES). Liquid-microjet UV PES is emerging as a valuable probe of the electronic structure of chromophores in solution. This tutorial lecture will include a brief review of the history of liquidmicrojet photoelectron spectroscopy and an explanation of the challenges facing UV PES of liquids. It will include a description of the design and operation of the recirculating liquid-microjet PES instrument we have built at UCL for studying samples that are available in relatively small quantities1 and illustrative liquid-microjet PES measurements of phenol2,3 and the green fluorescent protein (GFP) chromophore. [1] J. W. Riley, B. Wang, M. A, Parkes, H. H. Fielding, Rev. Sci. Instrum., 90 083104 (2019) [2] J. W. Riley, B. Wang, J. L. Woodhouse, M. Assmann, G. A. Worth, H. H. Fielding, J. Phys. Chem. Lett., 9 678-682 (2018) [3] A. Henley, J. W. Riley, B. Wang, H. H. Fielding, Faraday Discuss., DOI:10.1039/c9fd00079h (2019) Invited Tutorial Talk Time-resolved Structural Dynamics Thomas J. Penfold1 1 Chemistry- School of Natural and Environmental Science, Newcastle University Ultrafast studies emerged with the implementation of femtosecond-picosecond linear and nonlinear optical spectroscopies and had a huge impact on our understanding of chemical reactions, biological functions and phase transitions in materials owing to their ability to probe, in real-time, the nuclear motion within these different types of systems. However, for systems of more than two atoms the link between the optical domain spectroscopic observables and the molecular structure is ambiguous and therefore from the early days of ultrafast spectroscopy much effort was invested to develop methods that achieve both high temporal (on the femtosecond time scale) and spatial (on the order on tenths of an Angström) resolution. Capturing the evolving geometric, electronic and spin structure during the course of a chemical reaction or biological process is the principal aim of time-resolved X-ray techniques. The advent of X-ray free electron lasers introduces a paradigm shift in terms of the temporal resolution of X-ray techniques, and offers exciting possibilities for time-resolved second-order X-ray spectroscopies and non-linear X-ray experiments. In parallel, the improved data quality is making it increasingly important to accurately simulate the fine spectroscopic details. This has been the driving force for new theoretical methods permitting a detailed interpretation of the spectra in terms of the geometrical and electronic properties of the system. In this contribution, I will discuss some of the recent experimental and theoretical developments in ultrafast X-ray techniques and explore the new opportunities they offer. [1] C.J. Milne et al., Coord. Chem. Rev., 277, 44-68 (2014). [2] G. Capano, et al., J. Phys. B, 48, 214001 (2015). [3] T. Katayama, et al., Nat. Comm., 10, 1-8 (2019). Invited Talk To Boldly Look Where No One Has Looked Before: The Surprising Story of Acetylacetone Photochemistry I. Antonov,1 K. Voronova,2 M. W. Chen,1 B. Sztaray,2 P. Hemberger,3 A. Bodi,3 D. L. Osborn,1,* and L. Sheps1 1 Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, United States 2 Department of Chemistry, University of the Pacific, Stockton, California 95211, United States 3Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland * [email protected] The absorption of light by an organic molecule, and the subsequent pathways for energy transformation and release, are fundamental processes governing life on earth. Two of the most important electronic chromophores in organic systems are C=O bonds (carbonyl molecules) and C=C bonds (alkenes and polyenes). We have studied [1] the photodissociation of acetylacetone (AcAc), which exists at 300 K in the gas phase mostly as the enolone tautomer, rather than the diketo tautomer (see figure). The enolone tautomer is stabilized by both conjugation and an internal hydrogen bond. In a molecule such as this with more than one chromophore, it is interesting to consider whether AcAc’s photochemistry will be like that of a polyene or a ketone, or something different from either. Previous studies concluded that OH loss is the dominant (or only) channel when AcAc is excited in the ultraviolet at 266 or 248 nm. However, truly universal detection techniques were not used in these studies. By combining multiplexed photoionization mass spectrometery (MPIMS), threshold photoelectron photoion coincidence spectroscopy (TPEPICO), and time-resolved infrared absorption spectroscopy of OH radicals, we discovered that photodissociation of AcAc is much richer than previously presumed, and that OH production is not even energetically allowed following one-photon excitation at 266 or 248 nm. This work demonstrates the power of multiplexed, universal detection of charged particles in photodissociation studies, and lifts the veil on the photodissociation of a molecule that is both an enol and a ketone. [1] I. Antonov, K. Voronova, M. W. Chen, B. Sztaray, P. Hemberger, A. Bodi, D. L. Osborn, and L. Sheps, Journal of Physical Chemistry A, 123 5472 (2019) Contributed Talk Modifications of torsional potentials in the m-fluorotoluene and m-chlorotoluene cations D.J. Kemp,1,* A.R. Davies,1 L.G. Warner,1 E.F. Fryer1 and T.G. Wright1 1 School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK * [email protected] The coupling of methyl torsion and vibrational motions has been the subject of a series of studies on various substituted benzenes using a combination of fluorescence and photoionization spectroscopies.
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