科学美国人60秒 SSS 压缩钾原子跨越液态和固态（在线收听）

This is Scientific American's 60-second Science, I'm Christopher Intagliata.

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 a?t the same time. Specifically, they squashed simulated potassium atoms with really extreme pressures: 200 to 400 thousand atmospheres—that's at least 200 times greater than 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.

Thanks for listening for Scientific American — 60-Second Science. I'm Christopher Intagliata.

这里是科学美国人——60秒科学系列，我是克里斯托弗·因塔格里塔。

有固态。有液态。现在还有处于两者之间的状态——“链熔态”。

“钾在原子水平上会产生这种相互作用，形成介于固态和液态之间的混合态。”爱丁堡大学的凝聚态物理学家安德里亚斯·赫尔曼说到。

他和团队通过计算机模拟发现，在一定的压力和温度下，钾可以同时呈现液态和固态。具体来说，他们用极端压力压扁模拟钾原子，这一压力相当于20万到40万大气压，至少是马里亚纳海沟深度压力的200倍。

在这种压力下，原子形成两个连锁晶格。将晶格加热——温度不用太高，只要稍高于水的沸点就好——其中一个晶格会开始熔化，而另一个仍是固态。看，这就是链熔态。研究详情刊登在《美国国家科学院院刊》上。

赫尔曼表示，我们没有理由认为只有钾元素如此：其他六种元素也有这种晶体结构。至于我们会用它们来做什么？“我们还没有寻找其他应用。我认为这是相当基础的研究。”

有一件事是确定的：任何现实世界的测试都将面临巨大的压力。

谢谢大家收听科学美国人——60秒科学。我是克里斯托弗·因塔利亚塔。