水在液態(tài)時似乎有兩個不同的結(jié)構(gòu)

水在液態(tài)時似乎有兩個不同的結(jié)構(gòu)

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.

我們知道，如果沒有水，生命就不存在，但與其他液體相比，水就是個怪物。事實證明，這比我們想象的還要奇怪。日本科學家已經(jīng)證明，水在液態(tài)時不是一個，而是兩個不同的分子結(jié)構(gòu)——一個四面體和一個非四面體。

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

這一發(fā)現(xiàn)可能會對我們理解依賴液態(tài)水的生命系統(tǒng)產(chǎn)生影響。

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.

水在地球上很常見。與太陽系的其他星球相比，我們有一個非常潮濕的星球。我們沐浴其中;我們需要喝水;夏天我們還會徜徉其中。地球上所有的生命都依賴于它。然而水本身——古老的一氧化二氫——確實是一種奇特的物質(zhì)。

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。大多數(shù)液體冷卻時密度會增大，導致冰的密度比液體大。然而，水在大約4攝氏度(39.2華氏度)時達到最大密度。

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.

隨著溫度進一步降低，它的密度會降低，所以在冰點——大約0攝氏度(32華氏度)——它的密度比液態(tài)水小，會浮在水面上。

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，水具有異常高的表面張力，僅次于液體汞;它的熔點和沸點異常高;那么多其他化學物質(zhì)溶解其中，這也確實很奇怪。

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，來自英國和日本的科學家證明，這些奇特的性質(zhì)，與水分子在液體中的四面體排列有關。這意味著每一個水分子都是由氫和其他四個分子，以一個類似金字塔的形狀連接在一起。

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，它們到底是如何組織的，仍然是一個有爭議的話題。一種觀點認為水的分子結(jié)構(gòu)是單峰的——它是四面體向下延伸的。另一種觀點認為，這種結(jié)構(gòu)是雙峰的，由兩個結(jié)構(gòu)組成——四面體和其他一些東西。

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.

為了解決這個問題，東京大學的工業(yè)科學家進行了計算機模擬，并對液態(tài)二氧化硅進行了實驗。液態(tài)二氧化硅是已知的少數(shù)幾種具有四面體分子結(jié)構(gòu)的液體之一。

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.

“我們在結(jié)構(gòu)因子中首次給出了兩種局部結(jié)構(gòu)動力共存的清晰數(shù)值證據(jù)……支持液態(tài)水的雙態(tài)描述。”研究人員在他們的論文中寫道。

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

研究人員說，這一發(fā)現(xiàn)可能會對分子生物學、化學、藥理學以及工業(yè)應用產(chǎn)生影響。