Helen H. Fielding

Last updated
Helen Fielding

FRSC FInstP CPhys CChem
Born
Helen H. Fielding
Alma mater University of Cambridge (BA)
University of Oxford (DPhil)
Awards
Scientific career
Fields Physical chemistry
Institutions University College London
King's College London
University of Amsterdam
National Physical Laboratory
Thesis The Stark effect in atomic and molecular Rydberg states  (1992)
Doctoral advisor Timothy Softley [1]
Website www.ucl.ac.uk/chemistry/professor-helen-h-fielding

Helen H. Fielding FRSC FInstP CPhys CChem is a Professor of physical chemistry at University College London (UCL). [2] She focuses on ultrafast transient spectroscopy of protein chromophores and molecules. She was the first woman to win the Royal Society of Chemistry (RSC) Harrison-Meldola Memorial Prize (1996) and Marlow Award (2001).

Contents

Education

Fielding studied the Natural Sciences Tripos at the University of Cambridge. She began her PhD at the University of Cambridge, working with Timothy Softley, but moved with him to the University of Oxford where they studied excited quantum states using photoelectron spectroscopy. [1] [3] [4] She was awarded her Doctor of Philosophy degree in 1992. [1] [5]

Career and research

Fielding was a scientist at the National Physical Laboratory from 1992 to 1993. In 1993 she joined the University of Amsterdam as a postdoctoral fellow, working with Ben van Linden van den Heuvell. Here she worked on Rydberg wave packets in coulombic and magnetic fields. [6]

Fielding was appointed a lecturer at King's College London in 1994 after only 18 months of postdoctoral work. [7] She was the first woman to be awarded the Harrison-Meldola Memorial Prize in 1996. [8] She is interested in how to excite electron functions coherently, generating a wave packets with a localised probability distribution. [7] Electron movement occurs on the attosecond timescale, making them impossible to image using conventional laser technology. [9] Instead, Fielding employs femtosecond laser pulses to excite electrons to these highly excited Rydberg states. In these excited states, electrons behave both as a particle and a wave, and can be controlled using its wave-like characteristics. [9] She has become one of few worldwide experts in the field. [9] She is primarily interested in materials such as small organic chromophores and photoactivated peptides. [10]

She made the first observation of a wave packet in a Rydberg molecule in 2000. [11] This observation made her interested in coherent control, looking to exploit the phase of a rotating Rydberg molecule to manipulate the dynamics of chemical systems. [7] She explored the decay pathways of the Rydberg molecule NO. [7] Fielding use the wavelength and phase of the laser light to select whether NO decays via ionisation or dissociation. [7] One decay route will be the result of constructive interference and the other the result of destructive interference. [7] This study represented a breakthrough in the field; where light of a precise phase could be used to control molecular dynamics. [7] [12] She became interested in how the optical phase corresponds to the electronic and molecular phase, with a particular focus on the attosecond. [7]

Fielding was made an EPSRC advanced research fellow in 2001, and was the first woman to be awarded the Royal Society of Chemistry Marlow Medal. [8] [13] In 2003 Fielding moved to University College London, where she leads a large laser laboratory. [7] Her recent research has focussed on the dynamics of excited states formed during the absorption of ultraviolet light. [10] [14] She has studied the competition between internal conversion and electron detachment in protein chromophores. [15]

She has worked extensively on ultrafast chemical biology in the gas phase. [16] [17] [18] Fielding developed time-resolved photoelectron spectroscopy to study the relaxation dynamics of photoexcited molecules. [10] She has investigated the intramolecular dynamics of vibrationally and electronically excited benzene, and demonstrated new electron transfer pathways in pyrrole dimers. [19] [20]

Books

Awards and honours

Personal life

Fielding has two children. [16]

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References

  1. 1 2 3 Fielding, Helen H. (1992). The Stark effect in atomic and molecular Rydberg states. bodleian.ox.ac.uk (DPhil thesis). University of Oxford. OCLC   863543304. EThOS   uk.bl.ethos.314877.
  2. ↑ Helen H. Fielding publications from Europe PubMed Central
  3. ↑ Merkt, F.; Fielding, H. H.; Softley, T. P. (1993). "Electric field effects on zero-kinetic-energy photoelectron spectra: An explanation of observed trends". Chemical Physics Letters. 202 (1): 153–160. Bibcode:1993CPL...202..153M. doi:10.1016/0009-2614(93)85365-U. ISSN   0009-2614.
  4. ↑ Fielding, H. H.; Softley, T. P.; Merkt, F. (1991). "Photoionisation and ZEKE photoelectron spectroscopy of Ar, H2 and CO2 using a coherent XUV laser source". Chemical Physics. 155 (2): 257–265. Bibcode:1991CP....155..257F. doi:10.1016/0301-0104(91)87025-Q. ISSN   0301-0104.
  5. ↑ UCL (2018-01-15). "Chemistry Lab Dinner". Chemistry. Retrieved 2019-01-17.
  6. ↑ Wals, J.; Fielding, H. H.; Christian, J. F.; Snoek, L. C.; van der Zande, W. J.; van Linden van den Heuvell, H. B. (1994-06-13). "Observation of Rydberg wave packet dynamics in a Coulombic and magnetic field". Physical Review Letters. 72 (24): 3783–3786. Bibcode:1994PhRvL..72.3783W. doi:10.1103/PhysRevLett.72.3783. PMID   10056296.
  7. 1 2 3 4 5 6 7 8 9 July 2004, Cath O'Driscoll1. "Leading light". Chemistry World. Retrieved 2019-01-17.
  8. 1 2 3 "King's College London - Double success for young King's chemist". kcl.ac.uk. Retrieved 2019-01-17.
  9. 1 2 3 4 UCL (2006-06-20). "UCL scientist wins Corday Morgan medal". UCL News. Retrieved 2019-01-17.
  10. 1 2 3 Worth, Graham A.; Fielding, Helen H. (2018). "Using time-resolved photoelectron spectroscopy to unravel the electronic relaxation dynamics of photoexcited molecules" (PDF). Chemical Society Reviews. 47 (2): 309–321. doi: 10.1039/C7CS00627F . ISSN   1460-4744. PMID   29168864. Closed Access logo transparent.svg
  11. ↑ Fielding, H. H.; Stavros, V. G.; Boléat, E. D.; Verlet, J. R. R.; Smith, R. a. L. (2000). "The dynamics of Rydberg electron wavepackets in NO". Faraday Discussions. 115 (115): 63–70. Bibcode:2000FaDi..115...63S. doi:10.1039/A909794E. ISSN   1364-5498. PMID   11040501.
  12. 1 2 "2008 Moseley medal and prize". iop.org. Retrieved 2019-01-17.
  13. ↑ "King's College London - King's chemist wins top European prize". kcl.ac.uk. Retrieved 2019-01-17.
  14. ↑ Fielding, Helen H. (2018). "Molecular movies filmed at conical intersections" (PDF). Science. 361 (6397): 30–31. Bibcode:2018Sci...361...30F. doi:10.1126/science.aat6002. ISSN   0036-8075. PMID   29976813. S2CID   206667231.
  15. ↑ Tay, Jamie; Parkes, Michael A.; Addison, Kiri; Chan, Yohan; Zhang, Lijuan; Hailes, Helen C.; Page, Philip C. Bulman; Meech, Stephen R.; Blancafort, Lluís (2017). "The Effect of Conjugation on the Competition between Internal Conversion and Electron Detachment: A Comparison between Green Fluorescent and Red Kaede Protein Chromophores" (PDF). The Journal of Physical Chemistry Letters. 8 (4): 765–771. doi:10.1021/acs.jpclett.7b00174. PMID   28124921. Closed Access logo transparent.svg
  16. 1 2 Anon (2018). "Mothers in Science: 64 ways to have it all" (PDF). royalsociety.org. Royal Society . Retrieved 2019-01-17.
  17. ↑ Reid, Derryck T; Heyl, Christoph M; Thomson, Robert R; Trebino, Rick; Steinmeyer, Günter; Fielding, Helen H; Holzwarth, Ronald; Zhang, Zhigang; Del’Haye, Pascal (2016). "Roadmap on ultrafast optics". Journal of Optics. 18 (9): 093006. Bibcode:2016JOpt...18i3006R. doi:10.1088/2040-8978/18/9/093006. hdl: 11858/00-001M-0000-002C-3C9F-1 . ISSN   2040-8978.
  18. ↑ "Ultrafast chemical biology in the gas phase - Dimensions". app.dimensions.ai. Retrieved 2019-01-17.
  19. ↑ Parker, D. S. N.; Minns, R. S.; Penfold, T. J.; Worth, G. A.; Fielding, H. H. (2009). "Ultrafast dynamics of the S1 excited state of benzene". Chemical Physics Letters. 469 (1): 43–47. Bibcode:2009CPL...469...43P. doi:10.1016/j.cplett.2008.12.069. ISSN   0009-2614.
  20. ↑ Fielding, Helen H.; Worth, Graham A.; Kaltsoyannis, Nikolas; Kirkby, Oliver M.; Neville, Simon P. (2016). "Identification of a new electron-transfer relaxation pathway in photoexcited pyrrole dimers". Nature Communications. 7: 11357. Bibcode:2016NatCo...711357N. doi:10.1038/ncomms11357. ISSN   2041-1723. PMC   4844682 . PMID   27098394.
  21. ↑ Hall, Trevor; Gaponenko, Sergey V. (2009-11-24). Extreme Photonics & Applications. Springer. ISBN   9789048136346.
  22. ↑ Nalda, Rebeca de; Bañares, Luis (2013). Ultrafast Phenomena in Molecular Sciences: Femtosecond Physics and Chemistry. Springer Science & Business Media. doi:10.1007/978-3-319-02051-8. ISBN   9783319020518.
  23. ↑ Brouard, Mark; Vallance, Claire (2015-11-09). Tutorials in Molecular Reaction Dynamics. Royal Society of Chemistry. ISBN   9781782626145.
  24. ↑ "RSC Harrison-Meldola Prize Previous Winners". rsc.org. Retrieved 2019-01-17.
  25. ↑ "Glittering prizes". Times Higher Education (THE). 2001-08-03. Retrieved 2019-01-17.
  26. ↑ "RSC Marlow Award Previous Winners". rsc.org. Retrieved 2019-01-17.
  27. ↑ UCL (2007-10-08). "Success in Institute of Physics awards". UCL News. Retrieved 2019-01-17.
  28. ↑ UCL (2017-06-26). "RSC Award". Chemistry. Retrieved 2019-01-17.
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