Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Chemistry with sorted Molecules

04.10.2013
To gain complete control over chemical reactions is one of the main goals of chemists around the world.

Scientists at the University of Basel and the Center of Free-Electron Laser Science in Hamburg were able for the first time to successfully sort out single forms of molecules with electric fields and have them react specifically.


3-aminophenol conformers in a molecular beam are spatially separated in an electric field and react with calcium ions that have been localized in space by laser cooling.

Analysis of the reaction rates showed a relation between the spatial structure of the sorted molecules and their chemical reactivity. The results have been published in the renowned magazine «Science».

The reactivity of a chemical compound, that is the rate at which a substance undergoes a chemical reaction, is strongly influenced by the shape of its molecules. Complex molecules often exhibit different shapes, so-called conformers, in which parts of the molecules vary in their spatial arrangement. However, conformers often interconvert between each other under ambient conditions, so that a detailed study of their individual reactivities has been difficult so far.

Scientists around Prof. Stefan Willitsch from the Department of Chemistry at the University of Basel and Prof. Jochen Küpper from the Center for Free-Electron Laser Science in Hamburg (CFEL, DESY) have developed a new experimental setup that allows to study the reactivity of single isolated conformers. The scientists produced a beam of molecules from which they were able to pick specific conformers with a «molecular sorting machine» in order to specifically inject them into a chemical reaction.

The scientists made use of the fact that a change in the shape of a molecule usually also leads to the modification of its dipole moment. The dipole moment describes how a molecule reacts to an external electric field. Inside this sorting machine, a non-uniform electric field deflects single conformers to varying extents so that they are spatially separated.

In a first experiment, the scientists separated two conformers 3-aminophenol, a well-known compound that is widely used in industry. The two conformers only differ in the position of a single hydrogen atom. The separated conformers were then directed into a reaction chamber where they reacted with electrically charged calcium atoms, so-called ions, in a trap. The ions were cooled down with laser light to almost the absolute zero point of temperature scale at minus 273 degrees Celsius. In this way the ions were localized in space and formed an ideal target for reactions with the spatially separated conformers. Thus, the scientists were able to show that one of the conformers reacted twice as fast with the calcium ions than the other, a phenomenon that could be explained by the different electrical properties of the conformers.

The new method allows insight into fundamental reaction mechanisms and the relations between molecular conformation and chemical reactivity, with potentially far-reaching applications in chemical catalysis and the synthesis of new molecules.

Original Citation
Yuan-Pin Chang, Karol D³ugo³êcki, Jochen Küpper, Daniel Rösch, Dieter Wild, Stefan Willitsch
Specific Chemical Reactivities of Spatially Separated 3-Aminophenol Conformers with Cold Ca+ Ions

Science (2013) | doi: 10.1126/science.1242271

Further Information
• Prof. Dr. Stefan Willitsch, University of Basel, Department of Chemistry, Klingelbergstrasse 80, 4056 Basel, Tel. +41 61 267 38 30, E-Mail: stefan.willitsch@unibas.ch

• Prof. Jochen Küpper, Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607 Hamburg, Tel. +49 40 8998-6330, E-Mail: jochen.kuepper@desy.de

Reto Caluori | Universität Basel
Further information:
http://www.unibas.ch
http://dx.doi.org/10.1126/science.1242271

More articles from Life Sciences:

nachricht Bioenergy cropland expansion could be as bad for biodiversity as climate change
11.12.2018 | Senckenberg Forschungsinstitut und Naturmuseen

nachricht How glial cells develop in the brain from neural precursor cells
11.12.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Electronic evidence of non-Fermi liquid behaviors in an iron-based superconductor

11.12.2018 | Physics and Astronomy

Topological material switched off and on for the first time

11.12.2018 | Materials Sciences

NIST's antenna evaluation method could help boost 5G network capacity and cut costs

11.12.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>