Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Listen up! Experiment Records Ultrafast Chemical Reaction with Vibrational Echoes

03.09.2010
To watch a magician transform a vase of flowers into a rabbit, it's best to have a front-row seat. Likewise, for chemical transformations in solution, the best view belongs to the molecular spectators closest to the action.

Those special molecules comprise the "first solvation shell," and although it has been known for decades that they can sense and dictate the fate of nearly every chemical reaction, it has been virtually impossible to watch them respond. University of Michigan researchers Kevin Kubarych and Carlos Baiz, however, recently achieved the feat. Their work was published online Aug. 25 in the Journal of the American Chemical Society.

Until now, observing the solvent shell in action has been difficult for several reasons. First, fundamental steps in chemical reactions are exceedingly fast. To "film" a chemical reaction requires a camera with a "shutter speed" of femtoseconds (one femtosecond is the time it takes light to travel the length of a bacterium---about half a micrometer, or one hundredth the width of a human hair).

Second, a solution contains many solvent molecules, but only a few are privileged to be in the first solvation shell and participate in the reaction. Finally, most spectroscopic probes of liquids are not chemically specific, meaning they can't identify the particular molecular species they are monitoring.

To sum up, watching the first solvation shell respond to a chemical reaction requires a combination of ultrafast time resolution and the ability to initiate the reaction and track the solvent shell's response. It is this combination that Kubarych, an assistant professor of chemistry, and graduate student Baiz have achieved.

The key breakthrough was to realize that electrons move during chemical reactions and that when the nearest solvent molecules sense the electron redistribution, their vibrational frequencies change. Much as the strings on a musical instrument are intimately connected to the wooden neck and body, the solvent shell and the reacting molecule are tightly coupled and difficult to disentangle. Indeed, the very act of holding an instrument may cause it to warp or heat up and, in principle, these changes affect the frequencies of vibration of the strings. Similarly, the new approach to reaction dynamics introduced by Kubarych's lab essentially "listens" to the very fastest events in chemical reactions by noting the changing resonance frequencies of the surrounding molecules.

"This level of detailed information on the complex environments common in chemical transformations is unique," Kubarych said, "and promises to offer remarkable insight into the understanding of natural and artificial charge transfer reactions—processes that are of fundamental importance in contexts ranging from cellular respiration to solar energy conversion."

The research was supported by the National Science Foundation and the U-M Rackham Graduate School.

For more information on Kubaraych: https://www.chem.lsa.umich.edu/chem/faculty/facultyDetail.php?Uniqname=kubarych

Baiz: https://www.chem.lsa.umich.edu/chem/gradstudents/gradDetail.php?uniqname=cbaiz

Journal of the American Chemical Society: http://pubs.acs.org/journal/jacsat

Nancy Ross-Flanigan | Newswise Science News
Further information:
http://www.umich.edu

More articles from Life Sciences:

nachricht More genes are active in high-performance maize
19.01.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht How plants see light
19.01.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>