AEAS阅读训练 – Squeezed Potassium Atoms Straddle Liquid and Solid

Squeezed Potassium Atoms Straddle Liquid and Solid

There’s solid. And there’s liquid. And now there’s something in between called chain melt.

“At an atomic level you have this interaction and this mixup between liquid and solid.” Andreas Hermann is a condensed-matter physicist at the University of Edinburgh.

What he and his team have discovered, using computer simulations, is that under certain pressures and temperatures potassium can be both liquid and solid at the same time. Specifically, they squashed simulated potassium atoms with really extreme pressures: 200 to 400 thousand atmospheres—that’s at least 200 times the pressure in the depths of the Mariana Trench.

At that pressure, the atoms form two interlocking crystal lattices. Add heat to that—not too much, just a bit above the boiling point of water—and one of those lattices begins to melt while the other remains solid. Voila: chain melt. The details are in the Proceedings of the National Academy of Sciences.

Hermann says there’s no reason to stop at potassium: half a dozen other elements have this crystal structure, too. As for what we’ll do with them? “We haven’t really looked for any applications. It’s quite fundamental research, I’d say.”

One thing’s for sure: any real-world tests will face immense pressure.

压缩钾原子横跨液体和固体

有固体。有液体。现在中间有一种中间物质叫做链熔体。

“在原子水平上,液体和固体之间存在这种相互作用和混合。”安德里亚斯·赫尔曼是爱丁堡大学的凝聚态物理学家。

他和团队通过计算机模拟发现,在一定的压力和温度下,钾可以同时是液体和固体。具体来说,他们用非常极端的压力压扁了模拟的钾原子:20万到40万大气压——这至少是马里亚纳海沟深处压力的200倍。

这个压力下,原子形成两个相互连锁的晶格。加热——不要太过,只要稍稍高于水的沸点——其中一个晶格就开始融化,而另一个仍是固态。瞧:链融化。详情刊登在《美国国家科学院院刊》上。

赫尔曼说,我们没有理由止步于钾元素:其他六种元素也有这种晶体结构。对此我们应该怎么办?“我们还没有真正寻找任何应用。我认为这是非常基础的研究。”

有一点是肯定的:任何真实的测试都将需要“高压”。