Add evidence to the new hypothesis about water

According to new experimental evidence due to the collaboration among researchers at Stanford Linear Acceleration Center of the California Department of Energy, RIKEN Spring-8 synchrotron, together with Hiroshima University - Japan and Stockholm University - Sweden, photo The traditional picture of the structure of liquid water at the molecular level is wrong.

The team, including SLAC scientist Anders Nilsson, used advanced X-ray spectroscopy techniques to give a more detailed understanding of water molecular behavior. Published on the cover of the June 30 issue of Chemical Physics Letters, these findings may overturn legitimacy long ago around the most important compound of life.

Water in any form is a strange substance. It is not like any other liquid. It is extremely capable of carrying heat - that's why the Gulf Stream keeps Europe warm. The solid form of water is a stone that is lighter than water so it floats. Life on earth may not be formed if the oceans and lakes are frozen from the bottom. Water also has unusually large surface tension - an essential property for capillaries to work in plant roots and inside cells. These strange properties make water a very important substance for the existence of life.

Water is unlike any other liquid.(Photo: flickr)

Despite its popularity and importance, it has not been fully understood, and its molecular structure has been the subject of intense debates for decades. The stone has a long established structure, forming a tight tetrahedral trellis consisting of molecules adhering to four other molecules. The model of the water remains the same when the stone melts, the molecules loosen its network but are generally arranged in the same tetrahedral groups.

In a recent study, Nilsson and colleagues investigated the structure of liquid water with X-ray emission spectra and X-ray absorption spectra. These techniques use strong X-rays, due to the synchrotron light source generated. , to stimulate electrons inside a single oxygen atom of water molecules. Adjusting X-rays on specific energy layers can reveal the position and arrangement of water molecules with high precision. In this way, Nilsson's team found that the water was actually made up of tetrahedral groups, but clear evidence of the presence of a less obvious, less obvious structure also appeared.

The idea that liquid water is made up of two structures is not new. German physicist Willhelm Conrad Röntgen, who discovered X-rays at the end of the nineteenth century, published a work that suggested liquid water contained two distinct structures - a tetrahedral structure as in the form of ice and a more loose structure , which may help explain why water is such a strange compound. Now, after a century, current research is reviving Röntgen's 'two structures' model .

Recent X-ray spectroscopy has revealed that modern theories about the structure of liquid water are not correct.(Photo: Stanford Linear Acceleration Center)

According to Nilsson: 'Amazingly, the modern use of X-rays proved that Röntgen, more than 100 years ago, has been on the right track. Water is still not fully understood, although it is the foundation for our existence. I hope to discover more surprises in the future. '

The end of the debate about water molecules plays an important role in many areas such as medicine, chemistry and organisms. Modern molecular dynamics models, used to understand chemical and biological processes, are limited in their ability to predict water behavior.

Modern work is the most recent of the growing evidence for a new theory of liquid water structure. In 2004, Nilsson and colleagues raised controversy in a paper published in Science that suggests the tetrahedral model of water is incorrect. Nilsson agrees this debate is far from over and there is much to do before determining the nature of liquid water.

According to Jo Stöhr, director of the synchrotron Radiation Laboratory: 'In the last decade we have discovered that the types of matter seen as homogeneous express complex nano order. In my view, water work is another example of the true complexity of matter, this time for a simple liquid. Modern X-ray works seem to bring a whole new understanding of liquids and we may only see the beginning of a paradigm shift in current understanding. '