The question of how accurately protons move through water in an electric field has fascinated scientists for centuries. Now, more than 200 years after the last intuition of the phenomenon, scientists have some clarity.
In 1806 Theodor Grottos proposed a hypothesis known as: Cave mechanism For “proton jumping”, about how the charge flows through an aqueous solution.
While the Caves hypothesis was a very progressive thinking for its time, it came before it protonor even the actual structure of water, is even known: modern researchers have long known that it does not provide a complete understanding of what happens at the molecular level.
Recent discoveries on this topic may have solved the mystery by solving the long and elusive electronic structure of the water proton.
The results show that the protons move through the water in a “wagon” of three water molecules, with a “path” built in front of the train as it moves forward and stops as it passes.
This circle can continue to move indefinitely to move protons through the water. Although the idea has been proposed earlier, the new study identifies a different molecular structure that best fits the solution proposed by Grottos, according to the study authors.
“Discussions about the Grottos mechanism and the solubility properties of protons in water have ignited, as this is one of the most fundamental challenges in chemistry”, Chemist Ehud Pines says: from Ben-Gurion University in the Negev in Israel.
This new study is interesting because it combines a theoretical approach with physical experiments Made possible by modern technological advances. Researchers use X-ray absorption spectroscopy (XAS) to observe how proton charge affects electrons in a single oxygen atom in water.
As expected, the effect is greatest for the three water molecules, albeit to a different extent in each individual molecule in block three. The researchers found clusters of three molecules that form chains with protons.
The researchers also combined chemical simulations and quantum-level calculations to determine the interactions between protons and adjacent water molecules as the protons move through the liquid.
“Understanding these mechanisms is pure science, pushing the boundaries of our knowledge and transforming one of our basic concepts for one of the most important mass transport and delivery mechanisms in nature,” says Baines.
This invention plays an important role Other chemical processesincluding photosynthesis, cellular respiration and energy transfer in hydrogen fuel cells.
Not only is the solution exceptional, but also how the researchers got there: testing and validating theoretical predictions against experimental results and vice versa, in a long and torturous process that took nearly two decades from start to finish.
“Everyone has been thinking about this problem for over 200 years, so it was pretty hard for me to decide to tackle it.” says Baines. “Seventeen years later, I am grateful to have found and demonstrated a solution.”
Research published in International Edition of Applied Chemistry.
