Minutes before the examination …

Minutes after … Stephan celebrating, together with Pavel

April 26 – Stephan's Great Day: The Defense of his Thesis

Three years of hard work culminated in this special day – Stephan’s doctoral defense took place at Potsdam University on 26 April 2013. The committee of Prof. Matias Bargheer (chair), Dr. Christian Schüßler-Langeheine, Prof. Peter Saalfrank, Prof. Ralf Menzel, and Prof. Pavel Jungwirth judged him worthy of the degree after 90 minutes of examination. It is now time to celebrate his success and to relax after so much work and pressure (for all of us). While Stephan is heading far eastwards in his future, we send him off with these words: Thank you for the time you have shared with us and your ingenious work here at BESSY. And keep in touch!

Bernd prepares the setup in the new (reintroduced)
vertical alignment

The fluorescence spectrometer barely fitted in

Beamtime March - April 2013 – Extension of PE- and First Ever Optical Fluorescence Measurements on Charge Transfer Mechanisms in Solution

After modifying our differential pumping stage, we can now rotate the electron analyzer from a vertical to a horizontal position and to the magic angle. During the beamtime we made rich use of this new possibility. Triggered by the ICD kickoff-meeting at Schloss Waldthausen in January 2013, we were mostly interested in proton-transfer mediated charge-separation processes for which we conducted several isotope experiments.

From right to left: André, Andreas, and Philipp are making
Bernd happy with their exciting data

Josephina prepares solutions even in the middle of the night

We shared the second part of our beamtime with the group of Arno Ehresmann/André Knie from Kassel University, exploring ideas on characterizing ICD in liquid water through detection of UV/Vis photons. Together with Philipp, Andreas, Timo, and Andre we quickly got the experiment up and running, and even managed to collect very promising data. It’s been a good start.

Our friends from Olle Björneholm’s group came visiting in the last week. Josephina, Madeleine, Victor, Stephan, and Isaak started off with a tasty Vietnamese dinner, preparing for a long week inside a dark experimental hall. We continued measuring Amine solution.

Robert came for a visit to measure

Isaak and Stephan seemingly on duty, but this time we
had guests, who could handle a lot on their own

Beamtime January 2013 – Freezing Berlin welcomes guests from the warm Golden State

It’s time for doing some exciting experiments again, even if the year has just started. This time, our setup was fully in the hands of our guests from California. In the freezing cold Berlin, we welcomed John C. Hemminger and his team Allie Margarella, Marijke Van Spyk, and Kathryn Perrine… and, last but not least, Robert our Californian expat. Thus, we had quite experienced users at helm. This was well appreciated, as we had our hands full with the ICD meeting (see the last news) in the first week. While Robert dived into experiments with new solvents, John’s team was dedicating their time to ammonium. Manfred dropped by to see the experiment running again, even if it was only for a brief visit. Just one year ago we were dismantling our old setup; now we cannot remember how we worked with it at all with its many inconveniences. Stay tuned for yet more upgrades to the setup.

We finally catch John in a photo. He brought his
experienced team and also got Manfred on board
for a short visit

Marijke geared up to replenish the cooling traps – safety first!

 The meeting was held at an impressive castle

We spent the evening with Petr discussing new projects

January 16-18, 2013 – ICD Kickoff meeting (Research Unit FOR 1789)

This prestigious DFG research unit "FOR 1789" on Intermolecular / Interatomic Coulombic Decay (the project page offers plenty of information), is about to kick off. So what could be better than to have a “kick-off” meeting with all the important people joining for some insightful discussions? We headed south to Schloss Waldthausen, a castle in the forests not too far from Frankfurt. Here, every group presented their findings and prospects in talks and posters, which led to a lot of lively discussions in both the conference room as well as the ‘informal’ round table. One of the invited speakers was our colleague Petr Slavíček from Prague, and we used our chance to grab him to discuss publications. We got plenty of opportunities to talk to the many experts on ICD, including the pioneer Lenz Cederbaum. After three days, we closed the successful get-together with the realization: “ICD is everywhere”.

Isaak joins the team

Measurements can be funny, too

October / November 2012 - Isaak's visit at MAXlab

The group of Olle Björneholm from Uppsala University had one week beamtime at the I411 beamline at MAXlab, so Isaak used the opportunity to visit them. At the site he met Olle, Johan, Gunnar, Josephina, Victor and Tiger, and he learned how Liquid Jet PES is done in Sweden. Moreover, we had some interesting discussions and inspiration during night shifts. Thank you a lot for your kind invitation and for the joyful time in Lund!

Discussion with Ian

What might this be?

Beamtime September 2012 – Further upgrades to the new setup and lots of guests

We constructed a new cooling trap based on blueprints we got from Olle Björneholm's group in Uppsala, and were eager to test it. With the new trap we can now measure even very reactive solutions at magic angle. Moreover, Iain Wilkinson from Ottawa and Chaofan Zhang from Uppsala visited, and we had discussions about novel experimental techniques and visions. During the second week Josephina Werner joined from Uppsala to conduct exciting experiments on alcohol derivatives. In the last week Matthew Brown and Inga Jordan from the ETH Zürich took over, enjoying the performance and benefits of our new setup.

As usual, Bernd takes good care of the experiment

Matthew curiously inspecting the new setup

The XAFS conference in Beijing featured spacious
rooms for talks in a luxurious hotel

After a stressful day inside conference rooms or outside
on the street in the almost 40°C heat, we helped
ourselves to some local food. Here, Nick and Stephan wait
for the ingredients, which can be put on a hot plate (in the
center), while Emad reaches for the side dish.

July / August 2012 - Stephan visits Asia

One perk of being a physicist is that everybody travels around the world to present and learn science. This year, Stephan traveled in the other direction than the year before, as he went east to travel to Asia for the first time. There it was the perfect season to warm up from the usual cold German weather, with average temperature being 38°C. The first destination on the trip was China, where Stephan attended the 15th International Conference on X-ray Absorption Fine Structure, or XAFS15 for short, held in the imperial city Beijing. He joined forces with Emad, Kathrin, and Nicholas, who also attended the conference, to enjoy (and withstand) the humid weather and spicy food. After one week of scientific and cultural program it was time to move on to (relatively) nearby Japan.

After Stephan gave his talk at the seminar of Prof.
Suzuki at Kyoto University he was kindly invited to an
evening barbecue with the whole group. The rooftop outlook
let us enjoy the sunset behind the mountains around Kyoto
while grilling.

Following the kind invitation of Prof. Kosugi to visit the
UVSOR facility, Stephan took a quick train ride to
Okazaki. Here, the Institute for Molecular Science
resides on a hillside.

The next destination was Kyoto, where he met Prof. Toshinori Suzuki at Kyoto University. As an expert of time-resolved laser spectroscopy on liquid systems Prof. Suzuki was interested to hear about our work on angular dependency and scattering of photoelectrons, which Stephan presented in a departmental seminar. Prof. Suzuki also took the time to give Stephan a personal tour through his labs. The visit was completed by an invitation to a pleasant barbecue dinner with the whole group on a rooftop overlooking Kyoto at dusk. Stephan's second stop in Japan came at the invitation of Prof. Nobuhiro Kosugi, from the Institute of Molecular Science in Okazaki. After a short train ride with a brief stop in Nagoya, he was welcomed by Prof. Kosugi for a tour around the complex. This included a close-up tour within IMS’ own synchrotron facility UVSOR. Thanks for the warm welcome and kind hospitality, which made for a pleasant stay in Japan. As a whole the trip to Asia was quite a program, and a short week of vacation still in Japan afterwards helped to relax and further experience the Far East.

The latest beamtime crew playing happily with their new toy

Jet-catcher in action

Beamtime May 2012 - First run of the new setup and the jet-catcher

We have a new apparatus that, after testing thoroughly, will make many new experiments possible. Also following the trend of reuse and recycle, we got rid of the bulky LN2-traps and are now able to extract our samples back out in liquid form with the new jet-catcher system. With so many changes comes a lot to learn. Luckily we had helpful support from Robert, who came over from LA for a short visit, and our all-time genius friend Manfred, who was excited to see his catcher in action. And the catcher worked splendidly. With everything working so nicely, we decided to run some measurements in the magic angle alignment while we were at it, which now takes only a few hours to set up. Still, we will need some time to get used to the new apparatus, but we finished the beamtime with our heads full of ideas for new experiments.

Measuring with the magic angle geometry for real

Manfred excited about the working experiment

Isaak presents the delivered frame. It looks still pretty
stripped, though (one week left until beamtime starts… shock!).

Looking at the back of the frame with a demonstration of
the EA rotation mechanism (left: horizontal; right: magic angle).

Beginning of May 2012 - Finalizing the new Liquid-Jet apparatus

Months have passed since our old setup was put to rest, but now the time has come to assemble some new (and reused) parts to form the new apparatus. A completely new support frame was constructed; now featuring a convenient rotating mechanism for the EA. Our goal was to change the EA alignment for measurements at the horizontal and magic angle, and possibly everything in-between. The setup will also support the new jet-catcher system. The motto ‘everything should be easier and better than before’ was realized with more flexibility (easy alignment) and a more integrated system (ready to mount). But before the exciting experiments can begin, all these heavy parts have to be screwed together. With our new team member Isaak on board we were able to manage the assembly within the last week before beamtime.

The old EA was modified for its new place.

Some days of hard labor later: We finished everything just in time.

(front, from left to right) Gunnar, Johan, Joachim, and
Josephina discussing the setup of the new source

Stephan fiddles around with the apparatus

March 2012 - Stephan joins beamtime at MAX-lab

Stephan finally visits lovely Lund to join Olle Björneholm’s beamtime at MAX-lab. Together with Gunnar, Josephina, Joachim, and Tiger, he spent five days at the I411 beamlime, taking a close look at how microjet-PES is done over there. A bit later, Johan came over from Uppsala to join the team and we had some good discussions. Thanks a lot for the invitation and the nice time.

Stephan begins to dismantle the set up

Left: The EA worked hard for 8 years, and will continue
to serve us in the future. Right: The apparatus is now
stripped of most of its parts.

January 2012 - Starting to upgrade the Liquid-Jet apparatus

The time has come to upgrade our (t)rusty PES apparatus, which means ripping apart the old machine first. We extracted the essential parts of the setup, such as the electron analyzer and the cubic interaction chamber, and prepared them for further re-assembly. The construction of the new frame around the rearranged parts will be next.

Petr and Bernd going over our many projects

The great duo, Pavel and Bernd upon departure

End of December 2011 - Visiting Pavel Jungwirth and Petr Slavíček in Prague

Just after we got back from Sweden, with our heads full of ideas, our next trip was just around the corner. Bernd headed east to beautiful Prague, and was welcomed by Pavel and his group. Then Stephan followed for a joint session with Petr about our current ICD work. Thanks Petr and Pavel for the productive teamwork and hospitality.

Olle and Bernd at the discussion round table

Sitting together for lunch with the group

St Nicholas' Day, 2011 - Visiting Olle Björneholm and his group in Uppsala

The end of the year draws near. Soon it will be the time to settle down and prepare for Christmas. But not quite yet! We first wanted to visit our collaborators and discuss current and future projects to get fired up for next year. Starting to the north, we kindly got invited to Uppsala by Olle Björneholm to meet him and his group. Thanks for the prolific discussion rounds and the hospitality. We also got a glimpse at the impressive setup Johan Söderström has put together so far since his visit in August.

Niklas presents his thesis at the award ceremony

Prof. Dr. Wolfgang Gudat (left; Chairman of Friends
of Helmholtz-Zentrum Berlin e.V.) bestows the prize
on Niklas

December 01, 2011 - Niklas receives Ernst-Eckhard-Koch-Prize for his thesis

Niklas’ outstanding thesis was nominated for the annual Ernst-Eckhard-Koch-Prize awarded by the Friends of Helmholtz-Zentrum Berlin e.V.. And he got it! Congratulations, Niklas. After introducing his work to the audience with a compelling presentation at the HZB Users’ Meeting, he received the prize from Prof. Dr. Wolfgang Gudat.

Concept of the new setup

Upgrading the setup…

These were the last experiments performed with our vertical detection setup. The apparatus will now be rebuilt to a horizontal setup, and will be operational again soon. Look forward to some exciting improvements.

The night shift duo: Martin and Matthew

Robert, Ed, and David starting the machine

Beamtime October 2011 – Matthew Brown (ETH) / Martin Sterrer (FHI), and David Watson (University of Surrey); new rounds of nanoparticles in water

Our nanoparticle specialists are back for their second beamtime investigating nanoparticles in water. First, Matthew drove all the way from Switzerland and teamed up with Martin Sterrer from FHI to endure the night shift. Then, David Watson and Richard "Ed" Nicklin took over as last users of the old apparatus. They had all sorts of tricks up their sleeve, to keep these demanding solutions running. This also marks Roberts’ last beamtime as our group member. We hope to welcome you back soon as our guest (you still have to do the work, though).

Happy Robert just after his successful defense

All the important people of the day: Bernd, Robert,
Wolfgang Eberhard, Stefan Eisebitt, and Regine
von Klitzing

September 30, 2011 – Robert defends his thesis at TU Berlin

Today, Robert mastered the last challenge to becoming a doctor. In front of the committee of Wolfgang Eberhard (advisor), Stefan Eisebitt (secound advisor), and Regine von Klitzing (committee chair) he successfully defended his thesis at TU Berlin. After some stressful weeks it’s now time to celebrate. Congratulations, Robert! And many thanks for very good work and 3.5 nice years. Good luck with your new job with Stephen Bradforth at USC, Los Angeles.

John and Manfred discussing

Allie and Kathryn keeping the setup running

Beamtime September 2011 – Hemminger group doing experiments

Allie Margarella and Kathryn A. Perrine (from John’s group, Irvine) getting ready for the experiment. Meanwhile, John and Manfred are discussing the jet temperature. After getting familiar with everything in the first week, Allie and Kathryn were confident with the setup and pulled the nightshifts through on their own. And we used the opportunity to discuss with Manfred about some features of the upcoming upgrade of the setup.

Our guest Johan

Robert at the new flow cabinet

Beamtime July / August 2011 – Back at UE52-SGM

We are back at the UE 52-SGM beamline and use its variable polarization to further explore the polarization dependence of electron emission from neat water, at the surface and in bulk water. Here, observed low anisotropy parameters show a specific dependence on energy. This has interesting consequences for the electron Inelastic Mean Free Path (IMFP) in water.

Johan Söderström visits from Uppsala, and we spontaneously explore whether Post-Collision Interactions (PCI) occur also in the O1s ionization of liquid water. We also detected circular dichroism effects in the carbon 1s PE spectra of amino acids in water. Also, Robert enjoys our new mobile ‘chemistry lab’.

We thank Winfried Frentrup for support.

What’s new in June 2011


Faraday Discussion 160 – September 2012 in Oxford, UK

Make sure to mark your calendar! The 160st Faraday Discussion Meeting (FD160; go there) on ‘Ion Specific Hofmeister Effects’ will be held in September 2012 in Queens College Oxford, UK.
Organizers:  Pavel Jungwirth, Paul Cremer, Anthony Davis, Jonathan Goodman, Ruth Lynden-Bell, Paul Madden, Bernd Winter

Victoria Buch Memorial special issue

Tributes to Victoria Buch – A passion for science: Memories of Victoria Buch from her graduate strudent years and through her career (by R. Benny Gerber; here). For all contributed papers in this special issue 23 of volume 115 of the Journal of Physical Chemistry A see here.

Nottingham Prize for Tanza

Tanza Lewis from John Hemminger’s group (the group) wins the prestigious Nottingham Prize at the 71st Physical Electronics Conference for the best student paper presented at the conference (news, the prize). Tanza presented work on nitric acid dissociation (paper) and on CO2 capture by amines (paper). Congratulations!

The night-shift team

Beamtime May 2011 – Exploring nanoparticles in water with David Watson

Dave (see him here) and his student Richard "Ed" Nicklin explored aluminum and nickel nanoparticles in water – it’s not an easy experiment. Even making stable jets is complicated. Robert made sure that the machine runs the entire week, all night, every day, producing plenty of data.

Presenting the newly assembled CO2 'shaker'

Beamtime April 2011 – John Hemminger, Tanza Lewis, and Allie Margarella at BESSY

This is Allie’s first visit at BESSY, joining experiments on sulfuric-acid dissociation and more systematic studies of CO2 capture. We are glad that Manfred joined for exploring new experimental routes – ‘shaking’ aqueous solutions of varying CO2 content.

Robert being busy preparing stuff

February / March 2011 – Experiment at UE52-SGM

This is our first experiment where we explore polarization effects on the angle distribution of electrons emitted from an aqueous interface. The APPLE-II undulator UE52 allows rotation of the light polarization plane which replaces the need to rotate the whole detector including the main chamber. Although this beamline is more suited for high resolution than intensity, we conducted (polarization) angle dependent measurements of various solutions successfully.

We thank Winfried Frentrup, Patrick Hoffmann, and Antje Vollmer for support.

A collection of transition metal solutions

November / December 2010 – Experiment jointly with Steve Bradforth’s group (first part) and Matt Brown and Martin Sterrer from FHI (second part)

This time we had Anirban Roy joining from USC, and we were completing measurements on various nucleotides, DNA components, sulfates, phosphates, and some phenols in water. Experiments started slowly because of initial bad performance of our electron analyzer. Matt and Martin then initiated the very first PE measurements from nano particles in water. As usual, Robert found plenty of gaps over the course of this beamtime for his transition metal measurements to fit in.