Science Made Simple: Peter Schwerdtfeger on chemistry

Massey University's Distinguished Professor Peter Schwerdtfeger. Photo / Supplied

Surveys have shown one third of Kiwis think science is too specialised to understand. In this series, scientists who tackle mind-bogglingly complex problems each day make it simple for us. Today, we talk to Massey University theoretical chemist Distinguished Professor Peter Schwerdtfeger.

How would you describe what you do to a peer at a conference?

I am looking at fundamental aspects of how atoms and molecules interact with each other using quantum theory which goes beyond the nonrelativistic Schrodinger picture.

And then how would you to a stranger at a barbecue?

I am like a car mechanic except that the cars I am working on are really really small.

Quantum cars, so to say.

What project or projects are you currently working on at the moment and what's involved?

I am working on numerous projects.

Most are of fundamental nature: physics beyond the standard model, electroweak interactions to search for parity violation effects in chiral molecules, quantum electrodynamics of atoms and molecules, relativistic effects in superheavy elements, phase transitions in infinite systems, and on mathematical problems such as classification of polyhedra, confined quantum systems, and topological models for fullerene-like structures.

What are the trickiest questions facing your field and why is solving them so difficult?

One of the trickiest questions we solved was why mercury is liquid at room temperature - it is because of relativistic effects.

Ten years ago, we knew how to solve the problem, but we did not have the computational resources and technology available at that time.

Another notorious problem we face is related to a question raised by Max Born in 1940, of why some elements crystallise in a face-centred cubic structure instead of hexagonal closed packing.

In a hard sphere model, both packings are the densest achievable and identical.

But quantum theory makes a real difference as one has to account for the vibration of the atoms inside the crystal.

This gives a tiny energy difference between the two structures and explains why argon crystallises face-centred cubic and becomes hexagonal closed packed only at high pressures.

What do you feel are the most interesting or fascinating aspects of your field?

That every day I learn new things.

In science, you never stop learning, it is so exciting and rewarding.

Why do you think the work is important and what could it help us understand?

Our work already makes it into textbooks and the next generation will learn about our new discoveries.

We aim at a more complete picture of how nature works.