Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Moving molecule writes letters

27.02.2015

Caging of molecules allows investigation of equilibrium thermodynamics

On the search for high performance materials for applications such as gas storage, thermal insulators or dynamic nanosystems it is essential to understand the thermal behavior of matter down to the molecular level. Classical thermodynamics average over time and over a large number of molecules. Within a three dimensional space single molecules can adopt an almost infinite number of states, making the assessment of individual species nearly impossible.


The nanopore restricts the the freedom of movement of the adsorbed single molecule thus enabling scientists at Technische Universitat Munchen and University Lingkoping to model the equilibrium thermodynamics of single molecules.

Credit: Carlos-Andres Palma / TUM

Now researchers from Technische Universität München (TUM) and Linköping University (LIU) have developed a methodology, which allows to explore equilibrium thermodynamics of single molecules with atomic resolution at appreciable temperatures. The breakthrough study is based on two pillars: a technology which allows to cage molecules within two-dimensional nanopores and extensive computational modelling.

Trapped in two dimensions

At the Chair of Molecular Nanoscience and Chemical Physics of Interfaces at TU München, led by Prof. Dr. Johannes V. Barth, PD Dr. Florian Klappenberger developed the method to produce high-quality metal-organic networks on a silver surface. The network forms nanopores which restrict the freedom of movement of adsorbed single molecules in two-dimensions. Using scanning tunneling microscopy the researchers were able to track their motions at different temperatures with sub-nanometer resolution.

Parallel to the experiments, the researchers worked with sophisticated computer models to describe the temperature dependence of the dynamics of these single trapped molecules. "We have applied state-of-the-art supercomputer calculations to understand the interactions and energy landscape determining the motion of the molecules", says Jonas Björk of Linköping University.

Comparing experimental and modeled data the scientists unraveled that under certain conditions the integral theory approaches a simple projection of the molecular positions in space. This approach is central to statistical mechanics, but has never before been challenged to reproduce an experiment, due to the practically infinite molecular positions and energies one needed to consider without the nanoscale confinement.

Analogy to biology

"It was extremely exciting to employ two-dimensional networks as a confinement strategy to reduce the available conformational space of a single molecule, like a chaperone does with a protein", says Dr. Carlos-Andres Palma, the lead author of the study. "In analogy to biology, such form of confinement technology has the potential to establish sensors, nanomachines and possibly logics controlled by and made of molecular distributions."

Applying their knowledge of characteristic equilibrium configurations, the researchers carefully modulated the nanopore, thus making a single molecule write letters of the alphabet such as L, I and U, just by fine-tuning the temperature.

The research was funded by the European Research Council (ERC Advanced Grant MolArt) and the Swedish Research Council. The Swedish National Supercomputing Center provided supercomputing ressources. The research group of Professor Barth is member of the Catalysis Research Center (CRC) of the TUM.

Publication:

Visualization and thermodynamic encoding of single-molecule partition function projections
Carlos-Andres Palma, Jonas Björk, Florian Klappenberger, Emmanuel Arras, Dirk Kühne, Sven Stafström, Johannes V. Barth
Nature Communications, Feb 23, 2015 - DOI: 10.1038/ncomms7210

Media Contact

Andreas Battenberg
battenberg@zv.tum.de
49-892-891-0510

 @TU_Muenchen

http://www.tum.de 

Andreas Battenberg | EurekAlert!

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>