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Ames Lab Scientists' Surprising Discovery: Making Ferromagnets Stronger by Adding Non-Magnetic Element

Researchers at the U.S. Department of Energy's Ames Laboratory discovered that they could functionalize magnetic materials through a thoroughly unlikely method, by adding amounts of the virtually non-magnetic element scandium to a gadolinium-germanium alloy. It was so unlikely they called it a "counterintuitive experimental finding" in their published work on the research.

Cut U.S. Commercial Building Energy Use 29% with Widespread Controls

The U.S. could slash its energy use by the equivalent of what is currently used by 12 to 15 million Americans if commercial buildings fully used energy-efficiency controls nationwide.

How a Single Chemical Bond Balances Cells Between Life and Death

With SLAC's X-ray laser and synchrotron, scientists measured exactly how much energy goes into keeping a crucial chemical bond from triggering a cell's death spiral.

New Efficient, Low-Temperature Catalyst for Converting Water and CO to Hydrogen Gas and CO2

Scientists have developed a new low-temperature catalyst for producing high-purity hydrogen gas while simultaneously using up carbon monoxide (CO). The discovery could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

Study Sheds Light on How Bacterial Organelles Assemble

Scientists at Berkeley Lab and Michigan State University are providing the clearest view yet of an intact bacterial microcompartment, revealing at atomic-level resolution the structure and assembly of the organelle's protein shell. This work can help provide important information for research in bioenergy, pathogenesis, and biotechnology.

A Single Electron's Tiny Leap Sets Off 'Molecular Sunscreen' Response

In experiments at the Department of Energy's SLAC National Accelerator Laboratory, scientists were able to see the first step of a process that protects a DNA building block called thymine from sun damage: When it's hit with ultraviolet light, a single electron jumps into a slightly higher orbit around the nucleus of a single oxygen atom.

Researchers Find New Mechanism for Genome Regulation

The same mechanisms that separate mixtures of oil and water may also help the organization of an unusual part of our DNA called heterochromatin, according to a new study by Berkeley Lab researchers. They found that liquid-liquid phase separation helps heterochromatin organize large parts of the genome into specific regions of the nucleus. The work addresses a long-standing question about how DNA functions are organized in space and time, including how genes are silenced or expressed.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

SLAC Experiment is First to Decipher Atomic Structure of an Intact Virus with an X-ray Laser

An international team of scientists has for the first time used an X-ray free-electron laser to unravel the structure of an intact virus particle on the atomic level. The method dramatically reduces the amount of virus material required, while also allowing the investigations to be carried out several times faster than before. This opens up entirely new research opportunities.


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Chicago Quantum Exchange to Create Technologically Transformative Ecosystem

The University of Chicago is collaborating with the U.S. Department of Energy's Argonne National Laboratory and Fermi National Accelerator Laboratory to launch an intellectual hub for advancing academic, industrial and governmental efforts in the science and engineering of quantum information.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Cynthia Jenks Named Director of Argonne's Chemical Sciences and Engineering Division

Argonne has named Cynthia Jenks the next director of the laboratory's Chemical Sciences and Engineering Division. Jenks currently serves as the assistant director for scientific planning and the director of the Chemical and Biological Sciences Division at Ames Laboratory.

Argonne-Developed Technology for Producing Graphene Wins TechConnect National Innovation Award

A method that significantly cuts the time and cost needed to grow graphene has won a 2017 TechConnect National Innovation Award. This is the second year in a row that a team at Argonne's Center for Nanoscale Materials has received this award.

Honeywell UOP and Argonne Seek Research Collaborations in Catalysis Under Technologist in Residence Program

Researchers at Argonne are collaborating with Honeywell UOP scientists to explore innovative energy and chemicals production.

Follow the Fantastic Voyage of the ICARUS Neutrino Detector

The ICARUS neutrino detector, born at Gran Sasso National Lab in Italy and refurbished at CERN, will make its way across the sea to Fermilab this summer. Follow along using an interactive map online.

JSA Awards Graduate Fellowships for Research at Jefferson Lab

Jefferson Sciences Associates announced today the award of eight JSA/Jefferson Lab graduate fellowships. The doctoral students will use the fellowships to support their advanced studies at their universities and conduct research at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) - a U.S. Department of Energy nuclear physics laboratory managed and operated by JSA, a joint venture between SURA and PAE Applied Technologies.

Muon Magnet's Moment Has Arrived

On May 31, the 50-foot-wide superconducting electromagnet at the center of the Muon g-2 experiment saw its first beam of muon particles from Fermilab's accelerators, kicking off a three-year effort to measure just what happens to those particles when placed in a stunningly precise magnetic field. The answer could rewrite scientists' picture of the universe and how it works.

Seven Small Businesses to Collaborate with Argonne to Solve Technical Challenges

Seven small businesses have been selected to collaborate with researchers at Argonne to address technical challenges as part of DOE's Small Business Vouchers Program.

JSA Names Charles Perdrisat and Charles Sinclair as Co-Recipients of its 2017 Outstanding Nuclear Physicist Prize

Jefferson Science Associates, LLC, announced today that Charles Perdrisat and Charles Sinclair are the recipients of the 2017 Outstanding Nuclear Physicist Prize. The 2017 JSA Outstanding Nuclear Physicist Award is jointly awarded to Charles Perdrisat for his pioneering implementation of the polarization transfer technique to determine proton elastic form factors, and to Charles Sinclair for his crucial development of polarized electron beam technology, which made such measurements, and many others, possible.


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Oxygen: The Jekyll and Hyde of Biofuels

Scientists are devising ways to protect plants, biofuels and, ultimately, the atmosphere itself from damage caused by an element that sustains life on earth.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

New Perspectives Into Arctic Cloud Phases

Teamwork provides insight into complicated cloud processes that are important to potential environmental changes in the Arctic.

Mountaintop Plants and Soils to Become Out of Sync

Plants and soil microbes may be altered by climate warming at different rates and in different ways, meaning vital nutrient patterns could be misaligned.

If a Tree Falls in the Amazon

For the first time, scientists pinpointed how often storms topple trees, helping to predict how changes in Amazonia affect the world.

Turning Waste into Fuels, Microbial Style

A newly discovered metabolic process linking different bacteria in a community could enhance bioenergy production.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Electrifying Magnetism

Researchers create materials with controllable electrical and magnetic properties, even at room temperature.

One Step Closer to Practical Fast Charging Batteries

Novel electrode materials have designed pathways for electrons and ions during the charge/discharge cycle.


Coming to a Lab Bench Near You: Femtosecond X-Ray Spectroscopy

Article ID: 672457

Released: 2017-04-04 15:05:54

Source Newsroom: Lawrence Berkeley National Laboratory

  • Credit: Kristina Chang/Berkeley Lab

    Upon light activation (in purple, bottom row's ball-and-stick diagram), the cyclic structure of the 1,3-cyclohexadiene molecule rapidly unravels into a near-linear shape in just 200 millionths of a billionth of a second. Using ultrafast x-ray spectroscopy, researchers have captured in real time the accompanying transformation of the molecule's outer electron "clouds" (in yellow and teal, top row's sphere diagram) as the structure unfurls.

  • Credit: Tian Xue/Berkeley Lab

    Berkeley Lab postdoctoral researcher Kirsten Schnorr (left), chemistry Ph.D. student research assistant Andrew Attar (center), and postdoctoral researcher Aditi Bhattacherjee (right) make preparations for an experiment on the ultrafast X-ray apparatus.

The ephemeral electron movements in a transient state of a reaction important in biochemical and optoelectronic processes have been captured and, for the first time, directly characterized using ultrafast X-ray spectroscopy at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab).

Like many rearrangements of molecular structures, the ring-opening reactions in this study occur on timescales of hundreds of femtoseconds (1 femtosecond equals a millionth of a billionth of a second). The researchers were able to collect snapshots of the electronic structure during the reaction by using femtosecond pulses of X-ray light on a tabletop apparatus.

The experiments are described in the April 7 issue of the journal Science.

“Much of the work over the past decades characterizing molecules and materials has focused on X-ray spectroscopic investigations of static or non-changing systems,” said study principal investigator Stephen Leone, faculty scientist at Berkeley Lab’s Chemical Sciences Division and UC Berkeley professor of chemistry and physics. “Only recently have people started to push the time domain and look for transient states with X-ray spectroscopy on timescales of femtoseconds.”

The researchers focused on the structural rearrangements that occur when a molecule called 1,3 cyclohexadiene (CHD) is triggered by light, leading to a higher-energy rearrangement of electrons, known as an excited state. In this excited state, the cyclic molecule of six carbon atoms in a ring opens up into a linear six-carbon chain molecule. The ring-opening is driven by an extremely fast exchange of energy between the motions of the atomic nuclei and the new, dynamic electronic configuration.

This light-activated, ring-opening reaction of cyclic molecules is a ubiquitous chemical process that is a key step in the photobiological synthesis of vitamin D in the skin and in optoelectronic technologies underlying optical switching, optical data storage, and photochromic devices.

In order to characterize the electronic structure during the ring-opening reaction of CHD, the researchers took advantage of the unique capabilities of X-ray light as a powerful tool for chemical analysis. In their experiments, the researchers used an ultraviolet pump pulse to trigger the reaction and subsequently probe the progress of the reaction at a controllable time delay using the X-ray flashes. At a given time delay following the UV light exposure, the researchers measure the wavelengths (or energies) of X-ray light that are absorbed by the molecule in a technique known as time-resolved X-ray spectroscopy.

“The key to our experiment is to combine the powerful advantages of X-ray spectroscopy with femtosecond time resolution, which has only recently become possible at these photon energies,” said study lead author Andrew Attar, a UC Berkeley Ph.D. student in chemistry. “We used a novel instrument to make an X-ray spectroscopic ‘movie’ of the electrons within the CHD molecule as it opens from a ring to a linear configuration. The spectroscopic still frames of our ‘movie’ encode a fingerprint of the molecular and electronic structure at a given time.”  

In order to unambiguously decode the spectroscopic fingerprints that were observed experimentally, a series of theoretical simulations were performed by researchers at Berkeley Lab’s Molecular Foundry and the Theory Institute for Materials and Energy Spectroscopies (TIMES) at DOE’s SLAC National Accelerator Laboratory. The simulations modeled both the ring-opening process and the interaction of the X-rays with the molecule during its transformation.

“The richness and complexity of dynamic X-ray spectroscopic signatures such as the ones captured in this study require a close synergy with theoretical simulations that can directly model and interpret the experimentally observed quantities,” said Das Pemmaraju, project scientist at Berkeley Lab’s Chemical Sciences Division and an associate staff scientist within TIMES at SLAC.  

The use of femtosecond X-ray pulses on a laboratory benchtop scale is one of the key technological milestones to emerge from this study.

“We have used a tabletop, laser-based light source with pulses of X-rays at energies that have so far been limited only to large-facility sources,” said Attar.

The X-ray pulses are produced using a process known as high-harmonic generation, wherein the infrared frequencies of a commercial femtosecond laser are focused into a helium-filled gas cell and, through a nonlinear interaction with the helium atoms, are up-converted to X-ray frequencies. The infrared frequencies were multiplied by a factor of about 300.

The researchers are now utilizing the instrument to study myriad light-activated chemical reactions with a particular focus on reactions that are relevant to combustion.

“These studies promise to expand our understanding of the coupled evolution of molecular and electronic structure, which lies at the heart of chemistry,” said Attar.

Other co-authors of the study are Aditi Bhattacherjee and Kirsten Schnorr at Berkeley Lab’s Chemical Sciences Division and UC Berkeley’s Department of Chemistry; and Kristina Closser and David Prendergast at Berkeley Lab’s Molecular Foundry.  

The work was primarily supported by DOE’s Office of Science. The Molecular Foundry is a DOE Office of Science User Facility.

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Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel Prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.