Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'Gamers' method creates unique 4-D molecular spectral maps

19.04.2017

4-D spectral maps with new detail extracted via a multidimensional coherent spectroscopic method called 'GAMERS,' elucidating subtle effects governing the chemical, physical and optical properties of systems

Researchers at Northwestern University have created a new method to extract the static and dynamic structure of complex chemical systems. In this context, "structure" doesn't just mean the 3-D arrangement of atoms that make up a molecule, but rather time-dependent quantum-mechanical degrees of freedom that dictate the optical, chemical and physical properties of the system.


This is a simulated 4-D GAMERS spectrum shown as a 3-D cut through one spectral axis. Two dimensions encode information on vibrational frequencies, while the remaining dimensions represent electronic transitions in the molecule.

Credit: Harel

Consider how we view the world: three dimensions in space and one dimension in time, i.e., space-time. Remove any one of these dimensions and the view becomes incomplete and far more confused. For the same reason, this new method uses four spectral dimensions to resolve structure to reveal hidden features of molecular structure.

In this week's The Journal of Chemical Physics, from AIP Publishing, assistant professor Elad Harel and professor Irving M. Klotz, from the Department of Chemistry at Northwestern University, report a novel 4-D coherent spectroscopic method that directly correlates within and between electronic and vibrational degrees of freedom of complex molecular systems.

Harel's work involves a theoretical description of a recent experimental method developed in his lab, called GRadient-Assisted Multi-dimensional Electronic Raman Spectroscopy, or "GAMERS." It's a multidimensional coherent spectroscopic method in which the dimensions are the electronic and vibrational degrees of freedom of the system.

"Using multiple pulses of light, GAMERS probes how these different degrees of freedom are correlated to one another, creating a sort of spectral map that is unique to each molecule," Harel said. "[I]t demonstrates that subtle effects dictating the chemical, physical, and optical properties of a system, which are normally hidden in lower-order or lower-dimensionality methods, may be extracted by the GAMERS method."

Unlike other methods, this enables a uniquely detailed look at the molecules' energy structure in way that may offer predictive value.

"The shape of the potential surface, which is important for determining the kinetics and thermodynamics of a chemical reaction, may be directly measured," Harel said. "The level of molecular detail afforded by using more pulses of light to interrogate the system was surprising."

One potential application of GAMERS could be to pinpoint the physical mechanism of energy transfer during the earliest stages of photosynthesis, a question that remains controversial among researchers, according to Harel.

Right now, the main application of this work "is to enable insights into the physical mechanisms behind a host of quantum phenomena in a wide variety of chemical systems," Harel said. "These include singlet fission processes, charge carrier generation and transport in hybrid perovskites, and energy transfer in pigment-protein complexes. Understanding these processes has important implications for developing next-generation solar cells."

The GAMERS method is still in an early phase of development, according to Harel, but the team has high hopes for its future application.

"We believe technical advances could make such analysis far more widespread within the chemical physics community," said Harel.

###

The article, "Four-dimensional coherent electronic Raman spectroscopy," is authored by Elad Harel. The article will appear in The Journal of Chemical Physics April 18, 2017 (DOI: 10.1063/1.4979485). After that date, it can be accessed at http://aip.scitation.org/doi/full/10.1063/1.4979485.

ABOUT THE JOURNAL

The Journal of Chemical Physics publishes concise and definitive reports of significant research in the methods and applications of chemical physics. See http://jcp.aip.org.

Media Contact

Julia Majors
media@aip.org
301-209-3090

 @jasonbardi

http://www.aip.org 

Julia Majors | EurekAlert!

More articles from Physics and Astronomy:

nachricht CCNY physicists master unexplored electron property
26.07.2017 | City College of New York

nachricht Large, distant comets more common than previously thought
26.07.2017 | University of Maryland

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

CCNY physicists master unexplored electron property

26.07.2017 | Physics and Astronomy

Molecular microscopy illuminates molecular motor motion

26.07.2017 | Life Sciences

Large-Mouthed Fish Was Top Predator After Mass Extinction

26.07.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>