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– INSTITUT LUMIERE MATIERE in LYON (France) –

A 2 years post-doctoral fellowship in attosecond molecular science is available at the Institut Lumière matière (ILM, LYON, France), in the group “Excited states dynamics” ( http://ilm.univ-lyon1.fr/index.php?option=com_content&view=article&id=53&catid=22)

The candidate will use the ILM XUV beamline delivering attosecond and short (6fs) IR pulses at 5 kHz rep. rate, to perform pump-probe mass-spectrometry and velocity map imaging experiments on complex molecular systems. He/she will investigate coherent charge transport, non-adiabatic relaxation and XUV induced ultrafast processes in molecules.

The ILM is a large multidisciplinary institute of CNRS and Lyon university. It is composed of 300 members in 21 research groups working on a broad panel of research topics including: ultrafast science, nanophysics, analytical chemistry, biomolecules, liquid phase, theory, ion collisions etc…

The group “Excited states dynamics” investigates structures and dynamical processes in complex molecules using state-of-the-art tools of molecular science and ultrafast optics (see references).

Candidate should have skills in at least one of the following topics:

High harmonic generation and attosecond pulses, Femtochemistry, Velocity map imaging, Electrospray ionization source, Molecular physics, XUV radiation.

(Possible starting date: from February 15, 2016)

For application, send a CV to: Dr Franck LEPINE:  franck.lepine@univ-lyon1.fr

 

References:

Attosecond molecular physics: Fact or Fiction?
Lépine et al. Nature Photonics, 8, 195–204 (2014)

XUV excitation followed by ultrafast non-adiabatic relaxation in PAH molecules as a  Femto-Astrochemistry experiment
Marciniak et al Nature Communication, 6 , 7909 (2015)

Attosecond Hole Migration in Benzene Molecule Surviving Nuclear Motion
Despré et  al. J. Chem. Phys. Lett., 6, 426–431 (2015)

Probing time-dependent molecular dipole on the attosecond timescale
Ch. Neidel et al. Phys. Rev. Lett. 111, 033001 (2013)

 

Marie Skłodowska-Curie European Training Network: “ASPIRE”

 As previously announced, the “ASPIRE” ITN-ETN will commence in March and is recruiting twelve Early Stage Researchers (ESRs) to start their positions around September 2016.  These ESRs will have the opportunity to register for a PhD as part of their training, and will each be recruited to one of the nine academic and industrial member institutions located across Europe.

“ASPIRE” stands for “Angular Studies of Photoelectron in Innovative Research Environments”.  The ASPIRE network will focus on the measurement of Molecular Frame Photoelectron Angular Distributions (MF-PADs), which can be interpreted as electron diffraction patterns achieved by “illuminating the molecule from within”, and enable the electronic structure and dynamics of molecules to be interrogated. Progress in this area is highly technologically driven, requiring ever more sophisticated light sources and faster detectors.

Marie Skłodowska-Curie European Training Networks provide a unique experience for young researchers, who benefit from secondments and travel opportunities as well as network based training and research.   Successful candidates, who must fulfil the eligibility criteria concerning experience and mobility, will receive an attractive salary package, including generous mobility and family allowances, in accordance with the MSCA regulations for ESRs.

More details, including the projects and positions currently available, can be found on the ASPIRE website, www.ASPIRE-ITN.eu, which will be updated at regular intervals.  We would be grateful if you could direct this announcement to potential candidates.

 

STSM by Manuel Lara, Universidad Autonoma de Madrid (ES)  with Ivano Tavernelli, Zurich IBM Research (CH)Small_Fig
On November 16th, 2015 (6 days)
From SPAIN to SWITZERLAND

Interfacing DFT-like methods with classical motion to treat electron dynamics in aminoacids

Several theoretical works predicted the possibility of inducing ultrafast charge migration along the skeleton of large biological molecules upon their photoionization [1,2]. Recent experimental data together with the theoretical results obtained using a DFT-like methodology, captured for the first time the ultrasfast charge migration in the amino-acid phenylalanine after the interaction with a single attosecond pulse [3]. This first experimental evidence was obtained using a XUV-IR pump-probe scheme with an unprecedented attosecond resolution, measuring a doubly charged species to track the dynamics in the singly charged molecule. The theoretical method was able to reproduce the measured electron dynamics, accurately describing the pumped electronic wave packet that involved up to 34 ionic states leading to a highly delocalized hole and giving rise to charge fluctuations occurring in less than 4-5 fs. Despite the breakthrough of this joint experimental and theoretical work, a number of questions remains open, such that the role of nuclear motion and the possible fragmentation paths responsible for the lost of the double charged signal after a few tens of femtoseconds. In the present approach, we aim to include the nuclear degrees of freedom within a classical picture, combining our ab initio DFT-methods with existing CPMD (Carr Parrinello Molecular Dynamic) packages.
MANLA2_IMGThe main goal of this STSM was to learn the basic use of CPMD code in order to merge the current DFT-like methodology in the field ab-initio calculations of light-molecule interactions with the time-dependent picture of Ehrenfest dynamics for the physical problem of charge migration upon photoionization by XUV laser pulses. The first tests have already been carried out, although first definitive calculations and convergence checks will be perform within the next weeks. The computational cost of TDDFT dynamics is high in comparison with the previous approach, yet we expect to obtain clarifying results in the next weeks.

 

STSM by Hicham Agueny, University of Bergen (NO)  with Karoly Tőkési, Hungarian Academy of Sciences Institute for Nuclear Research, ATOMKI (HU)logo-ubergen
On November 15th, 2015 (9 days)
From NORWAY to HUNGARY

Multi-scattering effects in slow and fast ion-atom collisions

The main focus of this proposal is to broad our understanding regarding the multi-scattering phenomena in electron emission and electron transfer processes from atomic-target interacting with slow and fast ions. In order to reach this objective, the work is based on classical and nonperturbative approaches to deal with the electronic dynamics in time-dependent processes.

Our preliminary results for single electron capture in slow energies (2 keV/u) He2+ projectile colliding with a helium target, are presented in Fig. 1. Here the process is treated using a semiclassical close-coupling approach in combination with an Eikonal approximation to calculate the differential cross sections (DCSs) of the scattered projectile [1]. Our theoretical investigations are reported in two-electron processes to actively take part in the collision dynamics. The DCSs reveal oscillatory structure in the scattering angles θ, in agreement with the experimental data of Goa et al. [3]. The observed structure at large scattering angle has not been discussed neither theoretically nor experimentally, and therefore, its origin has not been explored yet.

HICHAG_imgFig. 1. Differential cross sections weighted by Sin(θ) in the laboratory frame for electron transfer at 2 keV/u 3He2+ – He collisions.

Several Max Planck Institutes for are seeking nominations for the position of Director in different research fields.

Directors pursue a bold research agenda and lead the institute jointly with their colleagues.

Nominees should have achieved distinction in their fields. Proven scientific or scholarly excellence and an innovative research program, rather than age or academic rank, are chief criteria for a directorship. We are looking for the strongest and most creative scientists worldwide, and
offer an international, excellent research environment, outstanding infrastructure and long-term scientific funding.

Nominations should include a curriculum vitae, a list of publications, and a brief description of the research program and should be sent as one PDF document to nominations.cpts@gv.mpg.de.

Nominations should be submitted by December 15, 2015, but later nominations may also be considered.

More information available here  here (52 downloads)

Following requests for deadline extensions and the upcoming holiday period, the deadline to submit abstracts for the special Issue “Femtochemistry” in Structural Dynamics has been extended to 15  February 2016.
Of course, all accepted papers are published online and assigned a DOI immediately and are, thus, also instantly fully citable.

Submission for papers is open at http://sd.peerx-press.org/cgi-bin/main.plex

Please consider to submit your work related to the field of femtochemistry and -biology, as well as ultrafast structural dynamics of molecules and (bio)chemical systems in the widest sense, to this special issue. The topical selection and the open access nature of the journal will provide the widest possible dissemination of your paper, and the joint publication of all papers in a single issue provides high visibility.

The 2nd XLIC Young Scientist Forum was held during the 3rd XLIC General Meeting in Debrecen, Hungary.

It was a special half-day with talks given by  young researchers (PhD students and post-docs). The committee of young researchers selected, on the basis of submitted abstracts, the following young speakers to give a talk at the YSF.

  • Sandra Gomez, University of Vienna, Austria
  • Katrin Tanzer, University of Innsbruck, Austria
  • Helena Levola, University of Turku, Finland
  • Michael Gatchell, Stockholm University, Sweden
  • Mark Stockett, AlbaNova University Center, Sweden
  • Aleksander Simonsen, University of Bergen, Norway
  • Morgane Vacher, Imperial College London, United Kingdom
  • Rudy Delaunay, Université de Caen – CIMAP, France
  • András Csehi, University of Debrecen, Hungary
  • Vera Krizova, J. Heyrovsky Institute of Physical Chemistry of the ASCR, Czech Republic
  • Dmitrii Egorov, University of Groningen, Netherlands
  • Thomas Kierspel, Center for Free-Electron Laser Science, DESY and Universität Hamburg, Germany

Young researchers participating at XLIC General Meeting also had the opportunity to present their results as a poster. Two poster sessions were organised in order to exchange views and stimulate discussions on research topics, and to support interdisciplinary communication between the researchers.

The 3rd General Meeting of COST Action CM1204 was organized by K. Tőkési at Centrum Hotel, Debrecen as chair and A. Csehi at University of Debrecen as co-chair.

The site of the Workshop, Debrecen – town since the 14th century – located in the North-Eastern part of Hungary, in the middle of the Hungarian Great Plain at a distance of 220 km (130 miles) from Budapest, is the second largest Hungarian city (with ca. 210,000 inhabitants).

The workshop was an annual meeting of CM1204 action, which deals with physical and chemical phenomena induced by electromagnetic fields and charged particles.

The objectives of workshop were to assess the state of the art in the current understanding of a variety of basic phenomena in the electron and atom dynamics such as charge-exchange processes collective as well as single-particle excitation and ionization, energy loss, and photon emission processes, collision induced physical, chemical and biological reactions radiation damage and materials modification.

The meeting included the following activities: 24 invited talks, 12 oral presentations by early stage scientists and 2 poster sessions. During the poster section 43 posters were presented. The XLIC MC meeting took place on November 2nd. The number of participants was 89.

The final program of the meeting can be found below with the photo of the participants.

The conference was very successful and useful for all participants. The oral lectures satisfied the high standard. During the free times between the sections we had fruitful discussions about the future plans. We have very positive feedbacks from the conference.

3rdXLIC-GM-group-picture-2

The Local Organiser,
Karoly Tokesy, Roland Eötvös Physical Society (Hungary)
e-mail: tokesi@atomki.mta.hu

Related links:

STSM by Mark Stockett, Aarhus University (DK) with Henrik Cederquist, Stockholm Universty (SE)
On October 25, 2015 (8 days)
From DENMARK to SWEDEN

Relaxation dynamics of laser-excited clusters at DESIREE

The purpose of this Short Term Scientific Mission (STSM) was to perform the first experiments with laser-excited cluster ions at the DESIREE (Double ElectroStatic Ion Storage Ring ExpEriments) infrastructure at Stockholm University. This project was motivated by one of the most exciting developments in recent years within the electrostatic storage device community, namely the observation of fast radiative cooling of hot, stored ions by Poincaré fluorescence, also called recurrent fluorescence [1, 2]. In this process, highly vibrationally excited ions initially in their electronic ground state undergo inverse internal conversion (IIC) to a low-lying electronic excited state. Once in the electronic excited state, emission of a single optical or UV photon rapidly decreases the internal energy of the molecule/cluster. The rate of radiative cooling by Poincaré fluorescence is much faster than the slow process of sequential emission of multiple IR photons corresponding to vibrational quanta of the hot electronic ground state.

We measured the delayed neutralization of C4 ions (a species for which Poincaré fluorescence has been observed before [3]) which survived one half-turn around the ring (about 20 µs) after being excited by 355 nm light from a ns pulsed Nd:YAG laser. This delayed signal probes the population of ions whose internal energy prior to excitation was such that the addition of one 3.5 eV photon placed them just at the threshold for electron detachment (3.9 eV), which is too low for Poincaré fluorescence to be active. The measured time constant with 355 nm excitation is consistent with infrared (vibrational) radiative cooling rates, but it is important to keep in mind that there is also a contribution to the population we probe due to cascade processes from above. Excitation at additional UV wavelengths will give a more complete picture of population dynamics of these cold ions.

Graph3

During the course of this STSM, a pulsed laser was interfaced to the DESIREE electrostatic storage ring for the first time. We succeeded in observing laser-induced decay of C4 ions and measured the vibrational radiative lifetime for clusters of very low internal energy which had not been studied previously. We also established a number of protocols and techniques for performing further systematic studies in the future. This effort has enabled a new class of experiments at DESIREE for studying the de-excitation dynamics of colder ions over longer timescales than is possible at non-cryogenic storage rings.

[1] S Martin et al. Phys Rev Lett 110 063003 (2013)
[2] G Ito et al.  Phys Rev Lett 112 183001 (2014)
[3] Kono et al. Phys Chem Chem Phys 17 24732 (2015)

 

STSM by Violaine VIZCAINO, CIMAP, Caen (FR) withThomas Schlatholter, Zernike Institute for Advanced Materials (NL)VVIZ_logos
On September 26, 2015 (10 days)
From FRANCE to NETHERLANDS

Radiation damage to human type II collagen fragments on the single molecule level

The purpose of the STSM was to study the radiation-induced molecular degradation of human type II collagen. We looked at the photo-fragmentation induced by both soft X-ray and XUV of two peptides: PK26-P [PGGPPGPKGNSGEPGAPGSKGDTGAK] which is made of a repetition of the amino acids sequence X-Y-Gly specific to collagen protein, and PK26-HyP [PGGP-HyP-GPKGNSGE-HyP-GA-HyP-GSKGDTGAK] which contains the unnatural hydroxyproline (HyP) residue.

Fragmentation of both peptides, in two different protonated states (M+3H)3+ and (M+4H)4+, were measured at different photon energies in order to highlight the main fragmentation channels, their threshold and the influence of hydroxyproline (HyP) residue in these processes. Figure 1 shows typical fragmentation spectra of (PK26-Hyp +4H)4+ at three different energies (14, 18 and 21 eV).

We expect to submit our results in a peer-reviewed scientific journal at the beginning of 2016. Moreover, this STSM has also allowed strengthening the collaboration between the CIMAP (Caen, France) and the University of Groningen (Netherlands).

VVIZ_img

Figure 1 : Fragmentation spectra of (PK26-Hyp +4H)4+. All spectra are normalized to the parent depletion.