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Next XLIC Expert Meeting will join WG1 and WG2 topics under the title “From Ultrafast to Ultraslow Dynamics in Molecules and Clusters”. It will be held in the Weizmann Institute of Science Israel , from 23th to 25th January  2017.

The workshop will bring together top researchers in a wide range of fields with the hope of establishing new interactions and future directions. The workshop participation is open to everybody and is jointly organised by COST CM1204 Action (XLIC). For more information please visit the conference website: http://www.weizmann.ac.il/conferences/UUDMC2016/

Abstract Submission Deadline: November 1st, 2016
Registration Deadline: January 5th, 2017

List of Invited speakers:
Noam Agmon, Hebrew University, Israel
Lars H. Andersen, Aarhus University, Denmark
Itzik Ben-Itzhak, Kansas State University, USA
Valerie Blanchet, CELIA, Bordeaux, France
Anastasia Bochenkova, Moscow State University, Russia
Steen Brondsted Nielsen, Aarhus University, Denmark
Philip Bucksbaum, Stanford, USA
Francesca Calegari, Politecnico Milano, Italy
Lorenz Cederbaum, University of Heidelberg, Germany
Henrik Cederquist, Stockholm University, Sweden
Brett Esry, Kansas State University, USA
Sharly Fleischer, Tel-Aviv University, Israel
Jason Greenwood, Queen’s University Belfast, UK
Christiane Koch, Universität Kassel, Germany
Ronni Kosloff, Hebrew University, Israel
Holger Kreckel, MPI-K Heidelberg, Germany
Stephen Leone, UC Berkeley, USA
Nimrod Moiseyev, Technion, Israel
Edvardas Narevicius, Weizmann Institute, Israel
Daniel Neumark, UC Berkeley USA
Thomas Pfeifer, MPI-K Heidelberg, Germany
Igor Schapiro, Hebrew University, Israel
Haruo Shiromaru, Tokyo Metropolitan University, Japan
Jan. R. R. Verlet, Durham University, UK
Mathias Weber, JILA, Colorado, USA
Roland Wester, Universität Innsbruck , Austria

Local Organiser: Yoni Toker (Bar Ilan University)

2nd WG1 Meeting “Ultrafast electron dynamics in molecules” (COST Action CM1204)
Edinburgh, UK.
29-30 August 2016

The second WG1 meeting of COST CM1204 Action was organized by Prof. Olga Smirnova and Dr. Adam Kirrander. It was aimed at presenting advances of all the nodes participating in the WG1 of the action, as well as to discuss problems and promote collaborations between all partners.

The meeting was organized into 6 sessions. Each session was moderated by a discussion leader. Each session opens with 10 min introduction to the field, presented by a discussion leader. The introduction was followed by 3 or 4 talks,  20 minutes each (without the questions). Each session was concluded by a 30 minutes general discussion involving 3 or 4 speakers (altogether at the stage, see pictures below) on the topics of their talks and topics suggested by the the discussion leader, who guided this discussion. The audience participated very actively in these discussions.  3 hot-topics were selected from contributed abstracts. The meeting also included 2 poster-sessions.

The number of participants was 78.
The final program of the meeting can be found below.

The Local Organiser,

Dr. Olga Smirnova

Max-Born Institute
Max-Born strasse 2a, 12489 Berlin
e-mail: olga.smirnova@mbi-berlin.de

Related links:

STSM by Pal Markus, National Academy of Sciences of Ukraine (UA) with Paola Bolognesi, CNR-ISM, Montelibretti (IT) iep-nasu cnr-ism
On May 23, 2016 (27 days)
From UKRAINE to ITALY

Ion induced fragmentation studies of halouracil molecules

The main objective of this STSM was to work on the experimental results previously obtained in the ion induced fragmentation of 5-BrUracil (5BrU) and 5-FUracil (5FU) at the GANIL ion beam facility in a collaboration between the CNR-ISM (Rome, Italy) and the CIMAP (Caen, France). These molecules are halogen substituted analogues of uracil molecule with radiosensitizing properties. In order to understand their fundamental mechanisms of radiosensitisation, it is essential to gain a clear characterization of their interaction with ionizing radiation in a ‘realistic’ biological environment mimicked by embeding them into pure and nano-hydrated clusters.

It is found that the environment has an overall ‘protecting’ effect, reducing the damage and the yield of low mass fragments. However, it is also responsible for the opening of new fragmentation channels and formation of ‘new’ species as a result of the altered molecular bonding conditions. The most striking result of the study is the appearance of a large number of hydrated fragments formed most probably due to a very strong water-molecule interaction holding the water clusters bound to the 5BrU molecule.

The main results will be published in an article (in preparation) where the discussion will be focused on how the presence of the Br atom in position 5 of the ring affects the fragmentation mechanisms of the uracil molecule [1] as well as the role of the environment in form of surrounding molecules of the same species or with the inclusion of water molecules in the fragmentation dynamics of 5BrU.

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Figure 1. The 36 keV 12C4+ ion induced mass spectrum of the 5BrU molecule (a), pure 5BrU clusters (b) and nano-hydrated 5BrU clusters (c) in the m/z region up to the monomer.

  1. Pal Markush, Paola Bolognesi, Antonella Cartoni, Patrick Rousseau, Sylvain Maclot, Rudy Delaunay, Alicja Domaracka, Jaroslav Kocisek, Mattea C. Castrovilli, Bernd A. Huberc and Lorenzo Avaldi. Phys. Chem. Chem. Phys., 2016,18, 16721-16729.

STSM by Milos Rankovic, Institute of Physics Belgrade (RS) with Aleksandar Milosavljevic, Synchrotron SOLEIL (FR)institu-of-physics-belgrade-logosynchrotron-soleil-logo
On July 16, 2016 (11 days)
From SERBIA to FRANCE

Probing the protein electronic structure by soft X-ray action spectroscopy

The motivation of this study is to see if the electronic structure of the protein can be correlated with its charge state, which defines the protein tertiary structure. Due to the Coulomb repulsion, protein precursors with higher charge states tend to unfold, or have elongated structures. Therefore, by roughly controlling the protein tertiary structure in the gas phase, we are able to investigate the influence on the protein electronic structure and give more insights into protein fundamental properties.
We used the near edge X-ray absorption fine structure (NEXAFS) method to obtain the absorption spectra from the trapped Ubiquitin and bovine pancreatic trypsin inhibitor (BPTI) protein ions, produced by an electrospray ion source (ESI). Several precursor ion charge states of these two proteins were isolated and subjected to the soft X-ray photons from PLEIADES beamline at SOLEIL synchrotron near Paris. Single ionization yields were obtained for different precursor charge states in C- and N-edge photon energy ranges. In the obtained spectra, we could clearly resolve the features corresponding to the Carbon 1s and Nitrogen 1s electron excitation into higher molecular orbitals. An example of our preliminary results obtained for BPTI protein in the C-edge energy range is presented in Figure 1.

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Figure 1 – Single ionization yields for the precursor charge state 5+ of the BPTI protein in the C-edge. Two peaks at about 284.5 eV and 288 eV correspond to the C 1s electron excitation into π*aromatic and π*amide molecular orbitals. The yield is normalized to the unity area under the curve.

The main goals of this STSM were successfully accomplished and we expect to publish the results in peer review journal as soon as possible. We plan to continue the collaboration with the new studies involving NEXAFS of other biologically relevant samples in the gas phase.

A collaboration project between the Synchrotron SOLEIL ( http://www.synchrotron-soleil.fr ), France  and the University of Turku (http://www.utu.fi/en ), Finland, is looking for candidates to apply for a 4 year funded PhD position.  The collaboration involves the PLEIADES beamline of SOLEIL and the Materials Research Laboratory in the Department of Physics and Astronomy of the University of Turku, and is aimed at developing and applying novel methods for gas-phase spectroscopy of fragile organic molecules.

While several fragmentation studies of soft x-ray irradiation of DNA bases or peptides exist, there is a lack of studies on neutral polypeptides or medium sized neutral biomolecules. Indeed, this is mainly due to their tendency to decompose during the heating phase, leading to their sublimation. The new technique, based on generation followed by flash vaporization of nano-droplets of a solution containing a specific molecules, will be combined with studies on the influence of electronic excited states after an excitation with soft x-ray synchrotron radiation. This targeted energy deposition can also lead to selective fragmentation of these floppy molecular edifices. The PhD student will be closely involved in instrumental development using electrospray and molecular cluster sources and will participate in experiments at SOLEIL, but also at other international synchrotron radiation facilities such as MAX-IV or at free electron lasers. The experimental methods consist mainly of electron spectroscopy, and electron-ion coincidence techniques. In addition, the student will participate in the general study programs of the graduate schools.

The successful candidate will enroll in both the Doctoral Program in Physical and Chemical Sciences of the University of Turku and the wave and matter doctoral school of the Physics of light and matter of the University Paris-Saclay, under a COTUTELLE double degree agreement.  The student will spend time at both partner institutions for courses and research, although the scheduling will be flexible.

After successful completion of the studies and the defence of the thesis, the PhD student will be granted a Doctor of Philosophy degree by both the Finnish and French universities.

To qualify, the candidates must have a recent Master of Science or equivalent degree in a relevant field.  The application deadlines are announced at the graduate school websites:

UTU-GS:  https://www.utu.fi/en/research/utugs/doctoralprogrammes/pcs/Pages

The nearest deadline is September 19th, 2016.

PLEIADES Beamline: http://www.synchrotronsoleil.fr/portal/page/portal/Recherche/LignesLumiere/PLEIADES

Contacts:            Prof. Edwin Kukk (edwin.kukk@utu.fi)
Dr Christophe Nicolas (christophe.nicolas@synchrotron-soleil.fr)

The 3rd XLIC WG2 Expert meeting (July 22-28, 2016) was focused on Delocalized Electrons in Atomic and Molecular Nanoclusters. It was organized by Klavs Hansen and took place at the Ettore Majorana Center for Scientific Culture, Erice, Sicily, Italy.

It was aimed at scientists, postdocs and graduate students who work with the effects of delocalized electrons with focus on free nanoclusters. Subjects such as quantum size effects, novel materials, and reaction pathways exhibit a range of phenomena which are highly sensitive to delocalized electrons’ mobility, screening, response, direct and exchange interactions, correlations, etc. The aim of the workshop was to bring together researchers in adjacent fields to examine recent and future developments.

XLIC-WG2meeting-Erice_IT-picture-3

The structure was workshop format of a week’s duration and included invited talks, selected oral presentations, a poster session, as well as time for individual discussions, as can be seen in the program below. The number of participants was 58.

The workshop was organized locally by the Ettore Majorana Center for Scientific Culture. The center, with the president Prof. Antonino Zichichiby, has a long and illustrious history of organizing such types of meetings. The workshop was in the framework of the International School of Solid State Physics, directed by Prof. Giorgio Benedek.

Klavs Hansen (Gothenburg, Sweden)
The Local Organiser

Related links:

  • WG2 Expert Meeting on Delocalized Electrons (Italy, July 2016) – Final program
  • WG2 Expert Meeting on Delocalized Electrons (Italy, July 2016) – Poster
  • WG2 Expert Meeting on Delocalized Electrons (Italy, July 2016) – Web site

STSM by Armin Scrinzi, Ludwig Maximilians University (DE) with Fernando Martin, Universidad Autonoma de Madrid (ES)
On April 11, 2016 (19 days)
From GERMANY to SPAIN

Absorption and electron spectra for small chemical systems

The momentum spectra of fragments emitted in laser-matter interaction are a main source of information about the internal dynamics. With tSurff a new and powerful theoretical tool was developed. The STSM was to introduce and implement the method in the group at UAM.

Implementations were designed and partially finished for emission from single- and multi-particle systems. This will, in certain applications, allow substantial speedup of calculations at UAM. Use with the XChem  code was laid out and implementation is in progress. In turn, the for LMU’s tRecX code, structural adaptions for a new interface to standard quantum chemistry structure were intiated. In a third line of development, adopting tSurff for breakup was discussed.

Outcome: the expertise for using tSurff has been successfully transferred to the UAM group. A collaboration for breakup has been agreed on. A new strategy for a quantum chemistry interface for tRecX has been adopted.

ARmin-img

Figure: tSurff for break up: partitioning of configuration space  (from an internal report)

ARMIN-logos

STSM by Manuel Yáñez, Universidad Autonoma de Madrid (ES) with Jean-Yves Salpin, LAMBE – Université d’Evry Val d’Essonne (FR)
On April 9, 2016 (22 days)
From SPAIN to FRANCE

Reactions of peptides and aminoacids with multiply charged ions. A theoretical and experimental perspective

The main goal was trying to gain insight on the toxicity of organomercury compounds and on the anticancer activity of cisplatin, by investigating their complexes with nucleobases through the use of InfraRed Multiple Photon Dissociation (IRMPD) experiments and high-level density functional theory (DFT) methods.

In the first case it has been found that the interaction of uracil, thymine and cytosine with RHgCl (R=CH3, n-Bu) results in the alkylation of the nucleobase, and the most stable structures have been characterized through IRMPD and high-level DFT calculations. In the second case, the interaction of cisplatin with uracil. and its thio and dithio derivatives was investigated using similar experimental and theoretical techniques, showing that several adducts are stable and contribute to the IRMPD spectra.

A poster, under the title  “Alkylation of nucleobases by organomercuric compounds: a gas-phase study” was presented in the Biennial conference on isolated biomolecules and bimolecular interactions. Mass spectrometry, spectroscopy, and theory, and we expect to submit one paper to Int. J. Mass Spectrom. along this year and at least a second, and probably a third one, in another peer reviewed journals.

MAYA2-imgIn the figure it can be seen a direct comparison of the experimental spectra for complexes of  2-thio-uracil with cisplatin and the spectrum simulated using B3LYP  calculations.

STSM by Judith Dura, MBI – Nonlinear optics and Short Pulse Spectroscopy (DE) with Luis Bañares, Universidad Complutense de Madrid (ES)
On April 13, 2016 (10 days)
From GERMANY to SPAIN

New energy transfer mechanisms in methyl iodide complexes unravel by femtosecond Coulomb repulsion

Multiphoton processes in atoms and molecules are highly probable upon ultrashort laser pulses irradiation. When the molecule is a Van der Waals cluster, there is a certain probability that within the same aggregate, one monomer experiences a neutral fragmentation channel, and a different monomer suffers an ionizing process. Within this particular situation, if a second laser pulse arrives it will ionize the fragment under neutral dissociation, which will experience a Coulomb repulsive force with the charge neighbour. Thus, the kinetic energy of the dissociated fragment will be modified as a function of the distance between the charge fragments. The kinetic energy trace of the Coulomb repulsed particles can be followed in time, i.e. charge particles distance, using the combination of ultrashort laser pump-probe techniques together with Velocity Map Imaging detection systems.
Figures 1 show 2D contour maps of the Centre of Mass (CM) kinetic energy (KE) of CH3 as a function of the time delay for λpump = 266 nm and λprobe = 333.5 nm a. Three time-dependent KE contributions can be distinguished.

Figure 1. Time-dependent ionization yield and Centre of Mass (CM) kinetic energy (KE) of photodissociation CH3 fragments at λpump = 266 nm and λprobe = 333.5 nm. Letters indicate time-dependent Coulomb repulsion trajectories.

 

 

 

Coulomb repulsion trajectories for the CH3 fragment in repulsion with the other CH3I of the dimer were simulated for the most stable dimer geometries (details of the calculations not given here) and compared with the experimental Coulomb repulsion trajectories.
The comparison suggest that trajectories A and B converge asymptotically to the neutral dissociation channels of the CH3I in the A-band.
An article with the outcome of this STSM has been writing at the moment to be send to Phys. Chem. Chem. Phys. in the next incoming months.

husiegel_bwSTSM by Alejandro Saenz, Humboldt-Universität zu Berlin (DE) with Piero Decleva, Universita’ di Trieste (IT)
On March 6, 2016 (6 days)
From GERMANY to ITALY

Photoelectron spectra for REMPI processes in (chiral) molecules

Chirality (the distinction of left and right mirror images) is one of the fascinating aspects of biology, since enzymes possess a 100% selectivity with respect to the stereochemistry of molecules. While the left-handed version of some molecule may be a very powerful pain reliever, its right-handed counterpart may be fully ignored by the human body, or, even worse, it may have fatal consequences.

Therefore, analytical tools for a very efficient and sensitive detection of the absolute configuration of a molecule is of great practical importance.

Some years ago the research group of Th. Baumert (Hassel, Germany) reported an asymmetry in the photoelectron angular distributions between two enantiomers of camphor as well as fenchone in (2+1) resonantly-enhanced multiphoton ionization. The similarity of the asymmetry may indicate some universal pattern which may pave a path to a sensitive detection tool for the absolute configuration of different enantiomers. In order to investigate this even further, it is of great interest to set up an approach that allows for the calculation of photoelectron angular distributions in resonant multiphoton ionization.

Within this STSM in Trieste a numerical approach for treating (2+1) resonantly enhanced multiphoton ionization, especially for extracting photoelectron spectra, was formulated and implemented. Two data sets for testing (hydrogen atom and the chiral molecule BrClFCH) were generated. During the STSM first tests for hydrogen atoms were performed by comparing the results with the ones of full solutions of the time-dependent Schroedinger equation. Furthermore, the STSM was used to clarify the strategy for extracting photoelectron distributions from the common Trieste/Berlin single-determinant time-dependent Schroedinger equation solver for arbitrary molecules and to prepare the resubmission of a joint publication.

REMPI-scheme_BrClFCH