水在液态时似乎有两个不同的结构

水在液态时似乎有两个不同的结构

Life as we know it wouldn't exist without it, but compared to other liquids, water is just a freaking weirdo. And, as it now turns out, it's even weirder than we thought. Scientists in Japan have demonstrated that water has not one, but two different molecular structures when in its liquid state - one tetrahedral and one non-tetrahedral.

我们知道，如果没有水，生命就不存在，但与其他液体相比，水就是个怪物。事实证明，这比我们想象的还要奇怪。日本科学家已经证明，水在液态时不是一个，而是两个不同的分子结构——一个四面体和一个非四面体。

That discovery, they say, could have implications for our understanding of living systems, which rely on liquid water.

这一发现可能会对我们理解依赖液态水的生命系统产生影响。

Water is pretty commonplace on Earth. We have a very soggy planet compared to the rest of the Solar System. We bathe in it; we drink it; we muck about in it in the summer. All life on Earth depends on it. Yet water itself - good old dihydrogen monoxide - is really peculiar stuff.

水在地球上很常见。与太阳系的其他星球相比，我们有一个非常潮湿的星球。我们沐浴其中;我们需要喝水;夏天我们还会徜徉其中。地球上所有的生命都依赖于它。然而水本身——古老的一氧化二氢——确实是一种奇特的物质。

There's its really weird density. Most liquids become more dense when they cool, resulting in an ice that is denser than the liquid. Water, however, reaches its maximum density at about 4 degrees Celsius (39.2 Fahrenheit).

它的密度很奇怪。大多数液体冷却时密度会增大，导致冰的密度比液体大。然而，水在大约4摄氏度(39.2华氏度)时达到最大密度。

As the temperature lowers further, it becomes less dense, so at freezing point - around 0 degrees Celsius (32 Fahrenheit) - it is less dense than liquid water and will float on top.

随着温度进一步降低，它的密度会降低，所以在冰点——大约0摄氏度(32华氏度)——它的密度比液态水小，会浮在水面上。

In addition, water has an unusually high surface tension, second only to liquid mercury; its melting and boiling points are unusually high; and that so many other chemicals dissolve in it is also really strange.

此外，水具有异常高的表面张力，仅次于液体汞;它的熔点和沸点异常高;那么多其他化学物质溶解其中，这也确实很奇怪。

In 2018, scientists from the UK and Japan demonstrated that these peculiar properties have to do with the tetrahedral arrangement of water molecules in liquid form. This means that every water molecule is hydrogen-bonded to four others in a rough pyramid shape.

2018年，来自英国和日本的科学家证明，这些奇特的性质，与水分子在液体中的四面体排列有关。这意味着每一个水分子都是由氢和其他四个分子，以一个类似金字塔的形状连接在一起。

But still, how the structure is ordered has remained a topic of debate. One model proposes that water's molecular structure is unimodal - it's tetrahedrons all the way down. The other proposes that the structure is bimodal, consisting of two structures - tetrahedrons and something else.

但是，它们到底是如何组织的，仍然是一个有争议的话题。一种观点认为水的分子结构是单峰的——它是四面体向下延伸的。另一种观点认为，这种结构是双峰的，由两个结构组成——四面体和其他一些东西。

To try and resolve the issue, industrial scientists from the University of Tokyo conducted computer simulations, and also ran experiments on liquid silica, one of the few other liquids known to have a tetrahedral molecular arrangement as well.

为了解决这个问题，东京大学的工业科学家进行了计算机模拟，并对液态二氧化硅进行了实验。液态二氧化硅是已知的少数几种具有四面体分子结构的液体之一。

We show the first clear numerical evidence in the structure factor for the dynamical coexistence of the two types of local structures ... supporting the two-state description of liquid water, the researchers wrote in their paper.

“我们在结构因子中首次给出了两种局部结构动力共存的清晰数值证据……支持液态水的双态描述。”研究人员在他们的论文中写道。

This finding could have implications for molecular biology, chemistry, and pharmacology, as well as industrial applications, the researchers said.

研究人员说，这一发现可能会对分子生物学、化学、药理学以及工业应用产生影响。