| Posted: Oct 18, 2017 |
Competing forces: How molecules maintain their structure
(Nanowerk News) A double helix twisted around itself: this is the distinctive structure of DNA, which is made up of large molecules. Using synthetically produced molecules, chemists and physicists at Martin Luther University Halle-Wittenberg (MLU) have investigated the forces which are at work inside the molecule to give it its three-dimensional structure. They have discovered that there are two primary forces at play that can strengthen or weaken one another.
|
|
The scientists have recently presented their findings in the international edition of the journal Angewandte Chemie ("Opposing Phase-Segregation and Hydrogen-Bonding Forces in Supramolecular Polymers").
|
|
Two main parameters determine structure formation: hydrogen bonds that attract one another, and so-called phase segregation, which ensures that molecules repel each another.
|
|
"It was previously assumed that the forces found in macromolecules had little influence over one another. There was a lack of research on forces contributing to structure formation, especially in solid polymers," says Professor Wolfgang H. Binder from the Institute of Chemistry at MLU.
|
|
In order to better understand how the molecules interact, the researchers produced simplified polymers. They examined these polymers in close collaboration with a team of physicists from the University of Halle, led by Professor Thomas Thurn-Albrecht and Professor Kay Saalwächter.
|
|
Using x-rays and magnetic resonance spectroscopy, the scientists tested whether the molecules assembled or repelled each other. It was discovered that the forces on boundary surfaces have a particularly strong influence on each other. The degree of influence depends on the size of the molecule, increasing with its size.
|
|
"The results help improve our understanding of the structure formation of polymers," says Binder.
|
|
They allow conclusions to be drawn about the material properties of, for example, self-healing materials, since the competing forces in such materials can now be more easily adjusted. Furthermore, the results enhance our knowledge about proteins, whose structures contribute significantly to their functionality.
|
