What is it about?

Water is the most abundant compound on our Earth’s surface. Its liquid phase also has apparently anomalous properties such as a reduction of its density on freezing (solids normally sink in their liquids, not float on them as ice does). So not surprisingly, scientists have been trying to understand its molecular structure in its liquid phase for many decades. This article follows these attempts from the late 19th century, setting them in the context of the scientific understandings of the time. Through exploiting the continual development of new experimental techniques that enable us to study the structure of liquid matter at the molecular level, allied to the development of advanced computational techniques to assist in the interpretation of the results of those experiments, we now have a consistent picture of the structure of this common – though fascinating – liquid. Not only can we understand the structural reasons behind its anomalous properties, but, though some of its behaviour in the supercooled region remains to be explained, we are now well equipped to explore water’s role in important biological and chemical processes.

Featured Image

Why is it important?

Water is critical in not only maintaining our environment but also in enabling many chemical, physical, geological and biological processes. With our present knowledge of water structure, and the experimental and computational techniques now available to us, we now have the tools to further explore the role of water in many important processes, in particular those that underpin life itself.

Perspectives

J.D. Bernal, one of the great polymaths of the 20th century, wanted to understand water’s role in biological systems. Though he published in 1933 one of the landmark papers on water structure, he realised that a real understanding of its structure required a major change in our understanding of the molecular structures of liquids in general. The picture of water that we now have is consistent with what he proposed. With the understanding and tools we now have, we can explore water’s behaviour, not only in the biological systems that stimulated Bernal’s interest, but also in other complex systems of physical and chemical importance.

John Finney
University College London

Read the Original

This page is a summary of: The structure of water: A historical perspective, The Journal of Chemical Physics, February 2024, American Institute of Physics,
DOI: 10.1063/5.0182665.
You can read the full text:

Read

Contributors

The following have contributed to this page