Crystallography is an extremely useful tool for analysing conventional materials. Using techniques such as x-ray diffraction, long range order and symmetry can be determined using principles such as Bragg’s law. The peaks produced in the associated diffraction patterns can yield valuable information about the atomic structure of these materials.
However, these techniques are generally not suited to nanomaterials as they lack long range order and produce few if any diffraction peaks, while the diffraction patterns themselves are often diffuse. A technique called atomic pair distribution function can be used on nano-sized materials. This non-conventional technique reads the information between the peaks produced using standard x-ray diffraction data.
Researchers at the Brookhaven National Laboratory have successfully used this technique to look at cesium ions in the nano-sized pores of a silicon-oxide zeolite (Si32O64). They were able to show that the cesium ions existed in zig-zag chains with short range order. They were also able to confirm that CsxSi32O64 was a room temperature stable inorganic electride.
Electrides are a novel family of materials that have recently begun to stimulate interest amongst the materials community. It is thought that they may be useful in the synthesis of materials as a reducing material or as a low energy electron emitter due to their electronic properties.