Noble gases as the ‘gold’ standard: liquid structure and fluid crossovers

From the beginning of disordered system diffraction, noble gases have served as the textbook example of a simple liquid structure. Yarnell’s liquid Argon data has been widely cited as the ideal structure of a liquid, and used to justify the use of the Lennard-Jones potential to qualitatively and quantitatively describe the structure of simple liquids. However, the dataset was smoothed by a non-disclosed procedure and the unsmoothed data have been lost. We therefore request 4 days of time on SANDALS to collect a dataset on liquid Krypton that can replace Yarnell's liquid Argon dataset as the gold standard of what a liquid S(Q) should look like. The time requested on SANDALS will also allow us to conduct an isothermal scan across various pressures at 135 K to establish whether, for a standard monoatomic fluid, the Frenkel line terminates on the vapour pressure curve as originally proposed in 2012 or continues to the triple point as proposed more recently by ourselves.

自无序系统衍射研究起步以来，惰性气体一直是简单液体结构的教科书式范例。Yarnell的液态氩数据被广泛引用为液体的理想结构，并被用于证明伦纳德-琼斯势（Lennard-Jones potential）可用于定性和定量描述简单液体的结构。然而，该数据集经过未公开的程序平滑处理，且原始未平滑数据已丢失。因此，我们申请在SANDALS上使用4天时间，采集液态氪的数据集——该数据集可取代Yarnell的液态氩数据集，成为液体结构因子S(Q)应具有形态的黄金标准。在SANDALS上申请的时间还将允许我们在135 K下对不同压力进行等温扫描，以确定对于标准单原子流体而言，弗伦克尔线（Frenkel line）是如2012年最初提出的那样终止于蒸气压曲线，还是如我们最近提出的那样延伸至三相点。