Dr Chris Syme
Ms. Joanna Mosses
Dr. Mario González Jiménez
Dr. Olga Shebanova
Mr Finlay Walton
Prof. Klaas Wynne
Frustrating liquid crystals
It is well-known that liquid crystals (LCs) are a state of matter in between the liquid and the crystal. In LCs, the molecules are partially ordered, for example, by all pointing in more or less the same direction. LCs have very wide ranging applications in display technology and optics generally.
Researchers at Glasgow University’s School of Chemistry led by Prof Klaas Wynne have discovered a novel LC phase in n-butanol that is not in between the liquid and the crystal. He explains “It is highly surprising that n-butanol forms a LC at all as this molecule is very much shorter than typical LC-forming molecules. Most surprising though is that this LC inhibits, or ‘frustrates’, the formation of the crystal”.
Research assistant Dr Chris Syme says “Using microscopy, we have been able to make movies showing that, if we force the formation of crystals somewhere in the liquid, these crystals do not penetrate the LC droplets, thus demonstrating the “frustration’ effect. We used confocal Raman microscopy to prove that we were dealing with a frustrating LC phase. The cherry on the cake was provided by synchrotron microfocus X-ray scattering at the Diamond Light Source in Oxford that allowed us to prove that we were dealing with a rippled lamellar phase.”
Wynne adds “This result may sound a little bit arcane but is has significant implications for our understanding of the formation of glasses that have myriad technological applications. The type of frustrated phase that we observe is likely to be unrecognised but common in liquids and therefore a template for many other liquids that supercool and form glasses.”
The paper entitled “Frustration of crystallisation by a liquid–crystal phase” is published in the Nature journal Scientific Reports on 17 February 2017 and is available for free download under a Creative Commons CC BY license at http://dx.doi.org/10.1038/srep42439.
Links
Prof Wynne researcher profile
Ultra{fast/slow} Chemical Physics group
The Diamond Light Source