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Chemistry is all about understanding electrons, for which a good dose of creativity is an absolute must

What today would encourage a teenage student to choose a career path in science? It can't be the money. It certainly isn't fame. Security of employment has gone out of the window for academic scientists and engineers, along with every other profession. And, as we all know, science is for people with no imagination or creative aptitude. I can remember a deputy head, himself a Cambridge graduate in classics, telling me so 25 years ago.

But he was wrong. Science is, perhaps, the most creative activity of all.

What attracted me to a life working in science was not the idea of spending hours in a laboratory carrying out painstaking experiments. It was the symmetry of nature which attracted me.

My motivation was the fascination of crystals, and the way that tiny particles, smaller than I could ever see, assembled themselves into perfect patterns.

This was a mystery I wanted to understand.

Fortunately, as an antidote to the "non-creative science" propaganda from one teacher, I was lucky enough at the same time to hear a lecture from another, more enlightened, member of that profession. The lecture was all about electrons.

Chemistry is concerned with the behaviour, the movement and the location of a fundamental particle called an electron. We know some things about this entity. We know what it weighs, and that it carries an electrical charge. We also know that it moves from atom to atom, changing the charge structure of chemical compounds during chemical reactions.

But when we try to look deeper into the nature of this particle, we come across some very serious problems. Exactly what is an electron?

Open up a chemistry textbook at a random page. You might see a description of an electron such as "an electron is a particle which occupies a point in space and carries a point charge".

Using this visualisation, we can see how these particles, like little charged billiard balls, move through a semi-conducting crystal from space to space. This is held to be the correct view of an electron.

After all, semi-conductors work, and semi-conductor technology powers our industries. But turn the page of our textbook and what do we find?

We learn that an electron can be described in terms of a propagated wave, like light. We can set up electron beams, and diffract them in solid crystals in the same way that we would diffract X-ray light. So, an electron can be a lump of solid matter ... or it can be a ray of energy.

But we haven't finished yet.

In order to describe how atoms bind themselves together into molecules, we have to imagine the electron to be not a travelling wave but a standing wave glued to an atom. These standing waves overlap and interact with the waves associated with other atoms.

This is what chemistry is all about. And yet in another area of chemistry known as crystal field theory we have to visualise electrons as behaving not as point charges or energy beams or standing waves but as charged clouds - smeared-out regions of electronic influence.

These clouds meet, overlap, commingle, or "feel" one another. This is the way in which we can try to understand the strange shapes which molecules adopt.

Point particle, standing wave, energy beam, charged cloud: I could go on. Which image is the right one? What does an electron really look like?

The answer is, frustratingly, all of the above and, at the same time, none of them.

Electron activity is like a football match. What you perceive is going on depends on where you are standing when you are watching it. The electron shows itself to us in a way which is determined by the type of observation we wish to make. Just think of an actor who plays a different part every night. If we go to see the actor play Hamlet, we don't expect him to dress up as a clown and pour water down his trousers. And, of course, we don't know the true nature of the actor himself, what he is like in real life. We see only what he reveals to us. The rest depends on our imaginations.

As a young research student, I worked on yet another image of the electron. What if electrons could be trapped inside a shell of water molecules? Then this electron - my electron - would look in its cage as if it was the size of a real billiard ball. Imagining this was the only way I could get through my work.

Soon after that I had to come down to earth and get a proper paying job. My first problem as an industrial chemist seemed somewhat more mundane than caging electrons. Why did the wheels keep falling off the fork-lift trucks? This was a problem of corrosion chemistry. And like all chemistry problems, the solution comes down to wondering where the electrons are and what they are doing.

And to solve such a problem, what is needed is, above all, imagination.

Allan Ashworth is an industrial chemist who works as a government regulator in the nuclear industry

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