Post-doctorat sur la ligne DESIRS et à l’ISMO : Dichroïsme Circulaire de Photoélectrons (PECD) du regime statique aux approches résolues en temps à la nanoseconde et à la femtoseconde

Situated at the heart of the Paris-Saclay cluster, approximately 20 km from Paris, SOLEIL is the French national synchrotron radiation source. In this large research infrastructure, the scientific experiments exploit the light from synchrotron radiation from the infrared to hard X-rays. Since 2008, SOLEIL has been serving many research fields in physics, biology and chemistry with applications in Materials Science, Structural Biology, Pharmaceuticals, Environmental & Earth Sciences and Cultural Heritage. SOLEIL, overseen by the CNRS and the CEA, provides its personnel with a multidisciplinary and internationally renowned working environment.

Within a national networking program on multi-scale/multi-dimensional approaches of chirality called TORNADO, gathering 13 teams in France, a 30 month-long post-doctoral research position is open, starting from April 2025 in the VUV beamline DESIRS group (led by Laurent Nahon) at Synchrotron SOLEIL. The candidate will be co-supervised by the CHIPIE group (led by Anne Zehnacker) at ISMO (Paris-Saclay University), located 2 km away so that he/she will be embedded in both groups. The position is centered around PECD, a very intense chiroptical effect, observed as a forward/backward asymmetry in the Circularly Polarized Light-ionization of isolated chiral species. PECD is known to be very sensitive to static and dynamic molecular structures like isomers, conformers and clusters (for reviews see [1,2]), as such perfectly suited to static as well as time-resolved pump/probe approaches to explore chiral structures and dynamics. A recently established collaboration between the DESIRS and ISMO teams, allowed bridging pioneering synchrotron and laser-based methods to explore some of the chemical dimensions of chirality (conformations and chiral complexes)[3-5]. In this collaborative context, and within the broader framework of TORNADO, the candidate will study static one-photon PECD (at DESIRS) and two-photon PECD at ISMO. Special emphasis will be put on systems whose electronic excited state dynamics can be probed by time-resolved multiphoton PECD on the ns timescale (at ISMO), and fs timescales (in collaboration with the HXUV group at CELIA/Bordeaux). We will be especially focusing on chiral complexes as well as axial chirality systems taking advantage of the exquisite sensitivity of the PECD observable to molecular structures. A second axis of research will be devoted to helical supra-molecular chirality, via static one-photon PECD on DESIRS, from small isolated species up to large chiral nano-objects, both custom-synthetized by chemists within the TORNADO network. The contract is for 1.5 years extendable for one year upon mutual agreement. Knowledge of French is not mandatory, but a fluent level of spoken and written English is required. The candidate is expected to hold a PhD in Physical Chemistry or Physics or Chemistry, since no more than 3 years. A solid background in gas phase molecular dynamics/spectroscopy is required, as well as experience in electron and/or ion mass spectrometry associated with molecular/effusive beams. Previous expertise on chirality, synchrotron radiation/laser systems or charged particle detection specially through imaging techniques is not mandatory but will be positively considered. Motivated candidates should contact by e-mail Laurent Nahon (laurent.nahon@synchrotron-soleil.fr) and Anne Zehnacker (anne.zehnackerrentien@cnrs.fr) providing a cover/motivation letter, CV and list of publications and contact details of at least two referees before December 15th 2024. Shortlisted candidates will be interviewed, online, in January 2025.

[1] L. Nahon et al., J. Elec. Spectrosc. Relat. Phenom. 204, 322 (2015).

[2] R. Hadidi et al., Advances in Physics: X 3, 1477530 (2018).

[3] J. Dupont et al., J. Phys. Chem. Lett. 13, 2313 (2022).

[4] E. Rouquet et al., Nat. Commun. 14, 6290 (2023).

[5] E. Rouquet et al., Angew. Chem. Int. Ed. Engl., e202401423 (2024)