New water research solves centuries-old mystery

Posted 15 December 2016

WaterUS scientists have had a “watershed moment” in understanding how water conducts electricity thanks to a new method for photographing the process.

The exact mechanics of “nature’s most mysterious relay race” have eluded scientists for more than two centuries. But researchers in the US have developed a process to sharpen previously blurry spectroscopic images of electricity passing through water.

"In essence, we uncovered a kind of Rosetta Stone that reveals the structural information encoded in colour," said lead researcher and Yale Professor Mark Johnson.

"We were able to reveal a sequence of concerted deformations, like the frames of a movie."

Previously, scientists used infrared colour changes to try and capture how water conducts electricity, but images were always blurry and unclear.

"In fact, it appeared that this blurring would be too severe to ever allow a compelling connection between colour and structure," Johnson said.

The solution was to work with only a few molecules of heavy water (water made of the deuterium isotope of hydrogen) and chill them to almost absolute zero. Then, using spectroscopy, the researchers finally witnessed it: sharp images of water molecules passing along protons.

Co-author and professor of chemistry at the University of Washington Anne McCoy said: “This fundamental process in chemistry and biology has eluded a firm explanation, and now we have the missing piece that gives us the bigger picture: How protons essentially ‘move’ through water.”

The researchers expect this improved understanding of how water conducts electricity to have a range of applications in further water research projects, including helping to determine if the surface of water is more or less acidic than the rest of its volume – yet another mystery to solve.