The influence of structure is everywhere; the properties of water and ice, the hardness of metals, the strength of magnets, and even the biology of DNA or the effect of antibodies on viruses – all depend on structure. For example, the structure of gold consists of close-packed atoms, much like a stack of oranges in the local supermarket. The planes of oranges can easily slip over each other, and for largely similar reasons gold is readily malleable.

There is another slightly less close-packed structure in which atoms are arranged at the corners of a cube, with another atom at the centre. The planes of atoms in this structure can slip less easily, and metals that adopt it, such as chromium, are less malleable.

This is a trivial example, and there are other structural reasons why some metals are harder – to do with 'impurities' and imperfections, which also pin atomic planes and stop them from slipping.

The articles published in the "chemistry" section of the ILL Annual Report show many examples of the relation between the structure and properties of new materials.

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