Chinese scientists make breakthrough in studying water structure

BEIJING, May 15 (Xinhua) -- Chinese scientists have revealed the atomic structure of a hydrated sodium ion, the basic chemical makeup of seawater, the China Daily reported Tuesday.

Scientists from Peking University and the Chinese Academy of Sciences, using China-developed new atomic force microscopy, have observed the atomic structure of the hydrated ions in their natural environment.

According to scientists, the technology can be used to study other water-based liquids, opening new avenues for molecular and materials sciences.

The research was published on May 14 in the journal "Nature".

It is the first time scientists have been able to visualize the atomic structure of hydrated ions since the notion was proposed more than a hundred years ago.

Since the late 19th century, scientists have been studying ion hydration, a process in which water dissolves soluble materials such as sodium chloride, or salt. Although the process is extremely common in nature, exactly how it works at an atomic level has remained a mystery.

Water is the most plentiful liquid on Earth. Its simple chemical structure - two hydrogen atoms bonded to one oxygen atom - is the basic building block of most life on Earth, said Wang Enge, lead researcher.

"But the science behind water, especially regarding its structure and interaction with other chemicals, is extremely hard and not well understood," Wang was quoted by the paper as saying. In 2005, the journal Science listed the structure of water as one of the most compelling scientific puzzles, despite a century's worth of research having been done.

"The main reason for water's complexity is its simplicity," said Jiang Ying, a professor at Peking University's International Center for Quantum Materials, who was part of the study.

Because hydrogen atoms are so simple and small compared with the oxygen atom, the weird properties of quantum mechanics start to interfere with experiments and make them less predictable, he said.

"Therefore, it is crucial for scientists to directly see how water interacts with other materials at an atomic level," Jiang said.

The research team also discovered that exactly three water molecules are needed to allow a single sodium ion to travel 10 to 100 times faster than other ion hydrates - a process that could lead to more efficient ion batteries, anti-corrosion coatings and seawater desalination plants, according to the Nature article.

This discovery also allows scientists to have a better understanding of how cells communicate with each other by exchanging ions through channels on their membranes, Jiang said.