Dr Beau Webber, from the University of Kent at Canterbury, undertook his experiment to characterise the atomic and mesoscale structure of a series of porous silica glasses. The wide continuous Q-range of Nimrod, currently optimized for 0.02Å-1 to 50.0Å-1, made the instrument ideal for this task.
The figure below shows Nimrod’s view of the differential scattering cross section of a mesostructured silica glass that has a hexagonal lattice of pores with a characteristic length scale of ≈110Å. A particular strength of the instrument is its ability to collect scattering data on an absolute scale, normalized to vanadium, across its entire Q-range. The corresponding pair distribution function clearly shows the ability of Nimrod to simultaneously resolve both the short range atomic structure of the glass, as well as the structural correlations of the porous network on a length scale of tens of nanometers.
Differential scattering cross section and corresponding atomic pair distribution function for a large pore, hexagonal framework, mesostructured silica measured on NIMROD
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Nimrod is now close to being fully operational and is accepting proposals through the standard ISIS mechanisms. The deadline for the current proposal round is midnight on Friday 16th October 2009. Further details on the capabilities of the instrument can be obtained from Daniel Bowron.