School of Chemistry, WestCHEM, University of Glasgow, UK.
Diamond Light Source, Harwell Science and Innovation Campus, Oxfordshire, UK.
Sci Rep. 2017 Feb 17;7:42439. doi: 10.1038/srep42439.
Frustration of crystallisation by locally favoured structures is critically important in linking the phenomena of supercooling, glass formation, and liquid-liquid transitions. Here we show that the putative liquid-liquid transition in n-butanol is in fact caused by geometric frustration associated with an isotropic to rippled lamellar liquid-crystal transition. Liquid-crystal phases are generally regarded as being "in between" the liquid and the crystalline state. In contrast, the liquid-crystal phase in supercooled n-butanol is found to inhibit transformation to the crystal. The observed frustrated phase is a template for similar ordering in other liquids and likely to play an important role in supercooling and liquid-liquid transitions in many other molecular liquids.
局部优势结构对结晶的阻碍作用在将过冷、玻璃化转变和液-液相变等现象联系起来方面至关重要。在这里，我们表明，正丁醇中假定的液-液相变实际上是由各向同性到波纹层状液晶转变相关的几何阻碍引起的。液晶相通常被认为处于液体和晶体状态之间。相比之下，过冷正丁醇中的液晶相被发现抑制了向晶体的转变。观察到的受阻相为其他液体中类似有序化的模板，可能在许多其他分子液体的过冷和液-液相变中发挥重要作用。
