New ‘Virtual Laboratory’ will change how we approach material chemistry

One would have to do the calculations in such tiny steps (less than a femtosecond) that you'd have to perform a gazillion (more than 10 billion steps) to get the system into the microsecond regime, which is just about relevant to real world chemistry, explains Prof Coveney. It would take years to carry them all out. No one is going to give you a supercomputer for that long, says Prof Coveney. And, besides, supercomputers are getting fatter, not faster, in that they can model larger slabs of matter, but for less time.

This has a surprising implication: we cant even convincingly work out how the boiling point of water and other basic properties emerge from the behaviour of its myriad molecules, viewed quantum mechanically.

Trial and error has been the order of the day. Walk around the Challenge of Materials gallery in the Science Museum and you will see the results of generations of experiments to figure out the link between a chemical recipe and desirable properties, from Egyptian glass to Thomas Heatherwick's first public commission: Materials House, a sculpture consisting of 213 layers of materials from Astroturf to Segovia lace.

The history of materials such as carbon-fibre-based materials, light-emitting diodes and high temperature superconductors teaches us that it can take decades from the discovery of a new material to honing it for real world applications.

Now Prof Peter Coveney, James Suter and Derek Groen have shown that it is possible to calculate the properties of a material from the bottom up, using supercomputers in the UK and Germany to extrapolate from the quantum domain where, in effect, all chemistry boils down to the behaviour of electrons, to slabs of material many microns in extent, comprising of millions of atoms.

They focused on composites of clays and polymers. Since the late Eighties, clays have been combined with synthetic polymers (such as nylon) to produce composites with superior properties such as enhanced strength for use in cars, aircraft and elsewhere.

At the atomic level, clay minerals consist of stacks of thin aluminosilicate sheets, based on aluminium, silicon, and oxygen atoms, separated by a few billionths of a metre. The sheets are about one micron across, stacked like a disordered pack of cards, with between a few sheets and one thousand in any single pile. The trick is to use a polymer to coax the sheets to organise in particular ways, a feat nature manages with ease in materials such as shell, bone and mother of pearl.

Prof Coveneys team found a way to simulate the properties of these composites, starting with their component electrons (to capture the way the polymer interacts with clay) through the movement of their atoms to the behaviour of millions of atoms. They compared characteristics of the virtual nanocomposites they synthesised in their virtual lab with the real thing and found they were reassuringly similar.

This feat is of profound interest because the problem of straddling different levels of understanding is common in science: we can see chemicals at work in the brain, map nerve connections and measure large scale flows of blood that take place during thinking but bridging these descriptions is tough.

When it comes to practical implications, this advance will speed the development of wonder materials. Take graphene, a two dimensional form of carbon, for example. The material shows so much promise in so many ways that an exhibition about it is already being planned at the Museum of Science and Industry in Manchester, where the great graphene pioneers and Nobellists Andre Geim and Kostya Novoselov work nearby in the university.

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New 'Virtual Laboratory' will change how we approach material chemistry