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

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

DGIST develops 20 times faster biosensor

24.04.2017 | Physics and Astronomy

Nanoimprinted hyperlens array: Paving the way for practical super-resolution imaging

24.04.2017 | Materials Sciences

Atomic-level motion may drive bacteria's ability to evade immune system defenses

24.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>