Vitrification of extremely simple molecules by constrainment in nano-spaces; heat capacity and dielectric relaxation measurements

通过对环己烷、四氯化碳和新戊烷分子间相互作用较小等热性质的研究，验证了过冷液的普适性。虽然已知普通液体的玻璃化转变温度(Tg)在每个熔化温度的1/2~2/3之间，但受检样品的玻璃化转变温度都低于预期温度，Tg的降低使这些物质在130K附近显示出热容的驼峰，这可能与液体从高温液态向稳定的低温液态结构有关。特别是，环己烷在154K时发生了一级相变，热容跃变剧烈，成为第一个用单分子液体的热容测量来研究液-液相变的例子。

The universality of supercooling liquid was examined by exploring the thermal property of the cyclohexane, carbon tetrachloride, and neopentane, such as having small inter-molecular interactions. Though, it is known that the glass transition temperature (Tg) of the ordinary liquid is in between 1/2 and 2/3 of each melting temperature, Tg of examined samples were all less than predicted temperature.The lowering of the Tg enabled these substances to reveal hump of heat capacities in the vicinity of 130 K, which might be related to the structuring of the liquid from high-temperature liquid phase to stable low-temperature liquid phase. In particular, cyclohexane showed 1st order phase transition at 154 K with sharp heat capacity jump and it became the first example to examine liquid-liquid transition by heat capacity measurements in a single molecular liquid.