Nav: Home

Snapshot of exploding oxygen

June 09, 2020

"The smaller the particle, the bigger the hammer." This rule from particle physics, which looks inside the interior of atomic nuclei using gigantic accelerators, also applies to this research. In order to "X-ray" a two-atom molecule such as oxygen, an extremely powerful and ultra-short X-ray pulse is required. This was provided by the European XFEL which started operations in 2017 and is one of the the strongest X-ray source in the world

In order to expose individual molecules, a new X-ray technique is also needed: with the aid of the extremely powerful laser pulse the molecule is quickly robbed of two firmly bound electrons. This leads to the creation of two positively charged ions that fly apart from each other abruptly due to the electrical repulsion. Simultaneously, the fact that electrons also behave like waves is used to advantage. "You can think of it like a sonar," explains project manager Professor Till Jahnke from the Institute for Nuclear Physics. "The electron wave is scattered by the molecular structure during the explosion, and we recorded the resulting diffraction pattern. We were therefore able to essentially X-ray the molecule from within, and observe it in several steps during its break-up."

For this technique, known as "electron diffraction imaging", physicists at the Institute for Nuclear Physics spent several years further developing the COLTRIMS technique, which was conceived there (and is often referred to as a "reaction microscope"). Under the supervision of Dr Markus Schöffler, a corresponding apparatus was modified for the requirements of the European XFEL in advance, and designed and realised in the course of a doctoral thesis by Gregor Kastirke. No simple task, as Till Jahnke observes: "If I had to design a spaceship in order to safely fly to the moon and back, I would definitely want Gregor in my team. I am very impressed by what he accomplished here."

The result, which was published in the current issue of the renowned Physical Review X, provides the first evidence that this experimental method works. In the future, photochemical reactions of individual molecules can be studied using these images with their high temporal resolution. For example, it should be possible to observe the reaction of a medium-sized molecule to UV rays in real time. In addition, these are the first measurement results to be published since the start of operations of the Small Quantum Systems (SQS) experiment station at the European XFEL at the end of 2018.
Publication: Photoelectron diffraction imaging of a molecular breakup using an X-ray free-electron laser. Gregor Kastirke et al. Phys. Rev. X 10, 021052

Images may be downloaded at this link:

Caption: During the explosion of an oxygen molecule: the X-ray laser XFEL knocks electrons out of the two atoms of the oxygen molecule and initiates its breakup. During the fragmentation, the X-ray laser releases another electron out of an inner shell from one of the two oxygen atoms that are now charged (ions). The electron has particle and wave characteristics, and the waves are scattered by the other oxygen ion. The diffraction pattern are used to image the breakup of the oxygen molecules and to take snapshots of the fragmentation process (electron diffraction imaging). Credit: Till Jahnke, Goethe University Frankfurt

Further information:

Professor Till Jahnke
Institute for Nuclear Physics
Goethe University Frankfurt
Tel.: +49 69 798-47025

Current news about science, teaching, and society can be found on GOETHE-UNI online (

Goethe University is a research-oriented university in the European financial centre Frankfurt am Main. The university was founded in 1914 through private funding, primarily from Jewish sponsors, and has since produced pioneering achievements in the areas of social sciences, sociology and economics, medicine, quantum physics, brain research, and labour law. It gained a unique level of autonomy on 1 January 2008 by returning to its historic roots as a "foundation university". Today, it is one of the three largest universities in Germany. Together with the Technical University of Darmstadt and the University of Mainz, it is a partner in the inter-state strategic Rhine-Main University Alliance. Internet:

Publisher: The President of Goethe University Editor: Dr. Markus Bernards, Science Editor, PR & Communication Department, Theodor-W.-Adorno-Platz 1, 60323 Frankfurt am Main, Tel: -49 (0) 69 798-12498, Fax: +49 (0) 69 798-763 12531,

Goethe University Frankfurt

Related Electrons Articles:

Self-imaging of a molecule by its own electrons
Researchers at the Max Born Institute (MBI) have shown that high-resolution movies of molecular dynamics can be recorded using electrons ejected from the molecule by an intense laser field.
Electrons in the fast lane
Microscopic structures could further improve perovskite solar cells
Laser takes pictures of electrons in crystals
Microscopes of visible light allow to see tiny objects as living cells and their interior.
Plasma electrons can be used to produce metallic films
Computers, mobile phones and all other electronic devices contain thousands of transistors, linked together by thin films of metal.
Flatter graphene, faster electrons
Scientists from the Swiss Nanoscience Institute and the Department of Physics at the University of Basel developed a technique to flatten corrugations in graphene layers.
Researchers develop one-way street for electrons
The work has shown that these electron ratchets create geometric diodes that operate at room temperature and may unlock unprecedented abilities in the illusive terahertz regime.
Photons and electrons one on one
The dynamics of electrons changes ever so slightly on each interaction with a photon.
Using light to put a twist on electrons
Method with polarized light can create and measure nonsymmetrical states in a layered material.
What if we could teach photons to behave like electrons?
The researchers tricked photons - which are intrinsically non-magnetic - into behaving like charged electrons.
Electrons in rapid motion
Researchers observe quantum interferences in real-time using a new extreme ultra-violet light spectroscopy technique.
More Electrons News and Electrons Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Warped Reality
False information on the internet makes it harder and harder to know what's true, and the consequences have been devastating. This hour, TED speakers explore ideas around technology and deception. Guests include law professor Danielle Citron, journalist Andrew Marantz, and computer scientist Joy Buolamwini.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at     You can read The Transition Integrity Project's report here.