Why do even specialists struggle with the structure of water?

We already know that most people have wrong ideas about the structure of water (see last post). In this post we will show that even specialists have difficulties to make sense of the water structure. In spite of the many existing scientific models, none of them has been chosen to be the ultimate one. Is this a problem? How bad is it that our scientific knowledge still has some blind spots? It is not bad at all. Blind spots are a blessing, challenging researchers to tackle new problems. They are just a normal part of scientific evolution. There is a problem, though: nobody seems to be aware of the black hole around the water model.

Hydrogen is the most important component of water.

Water is the most abundant molecule on the planet earth.  It plays a dominant role in our climate and the energy balance of our planet. It is essential for life and has an enormous impact on our health. It is one of the best solvants making a big variety of chemical reactions possible. Water is the burning product of hydrogen, the fuel of the future. It has almost 100 anomalies, properties that are fundamentally different compared to similar substances. The fact that ice floats is the best known one. Water also has the highest heat capacity of all fluids. This means that the movement of the water molecules is very complex, i.e. has a lot of degrees of freedom. It is this complex movement that is difficult to tackle. For the outside world, science gives the impression that everything of water is known, but its essence remains obscure. This makes it very likely that we still miss the real potential of water.

Back to our central question: why haven’t the specialists found the one model for water? The answer is, in my humble opinion, that they focus too much on details, thereby losing sight of the simplicity.
Scientists adore microscopic models. These models describe the macroscopic reality on a microscale, thereby explaining the macroscopic properties. From our last post, we know that in a good water model:

1. the majority of the water molecules are hydrogen bonded to the other water molecules (the melting heat of ice is much smaller than the sublimation heat of ice),
2. the water molecules are on average closer to each other than in ice (ice floats on water), and
3. only a small fraction of the water molecules can easily move with respect to each other (explaining the fluidity). 

The model of the average textbook, in regard to completely free moving water molecules, is in conflict with our findings in number 1 (above) and ought to be forgotten as soon as possible. Water specialists are of course aware of this, so all water models start form the dominant presence of hydrogen bonds.

For over a hundred years we have been searching for a good microscopic model (the first models were from Whiting (1884) and Rontgen (1892)). Tens of variations on these original models have been developed. A chronological overview can be found on the website of Martin Chaplin who deserves a statue for making overviews of all the water research. A helpful guide for everybody trying to get some grip on this wide research field.

Different mixture models. Left: low-density structures,
Right high-density structures

The most popular models for the water structure nowadays are mixture models. These models assume that water consists of two or more different phases that can exchange very quickly (in some models on a time scale of picoseconds). There is always a phase with a high density (with more broken bonds) and a phase with a lower density (with fewer broken bonds). Fluidity is explained as well, because in several models one or two of the phases are liquid themselves. When this is not the case, the rapid exchange between the two phases allows water molecules to move on a local scale.

All existing mixture models explain our three macroscopic properties described above, but there are tens of anomalies to go. No model can deal with all of them. One model explains some more properties than the other but until now no clear champion is found. But one thing becomes clear. Whereas the original models were rather simple and were described with mathematical equations, the most recent models are far more complex and completely based on computer simulations.

Apparently, the more anomalies we want to explain, the more the mixture models become complex.  We are replacing the complex properties of liquid water with a complex model. The question is if this brings us any further? If we really want to understand the role water plays in living cells or how it interacts with electromagnetic fields we need a simple water model. Preferably this model is described with mathematical equations and allows us to visualise the water structure clearly. The mixture models do not offer much perspective in this respect. A heterogeneous mixture is difficult to describe mathematically because a lot of parameters play a role. What is the size and shape of the phase clusters? What happens exactly at their contact surface? Do these clusters perfectly fit together or are there holes in the structure?  How do all these parameters depend on temperature and pressure? … Also, the most recent and popular model (suggesting that water exists out of 2 liquids) focuses on anomalies that are unimportant (a post about this will follow).

The past years I took the challenge to develop a simple analytical model for water. I was therefore inspired by an old model (of the sixties) seeing water as homogeneous. I was able to improve the model significantly and succeeded to use the model to explain some electromagnetic properties (and corresponding anomalies) of water. The results are written down in some preprints. The scientific community still have to give their fiat for the model (the preprints will be sent to a journal the beginning of October).

The forthcoming months, the strongest images and consequences of my model will be explained so you can judge for yourself if there is any potential. You will also able to follow how the scientific community reacts to this new approach.