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Updated: Aug 8, 2026

X-ray Powder Diffraction in Conservation Science: Towards Routine Crystal Structure Determination of Corrosion Products on Heritage Art Objects
Published on: June 8, 2016
The 136-atom structure of ZrP2O7 and HfP2O7 from powder diffraction data
Graham W Stinton1, Matthew R Hampson, John S O Evans
1Department of Chemistry, Science Laboratories, University of Durham, South Road, Durham, DH1 3LE, UK.
Abstract:
There has been considerable debate in the literature about the true room-temperature structure of ZrP2O7 and related materials. In this article we describe how a combination of information from solid-state 31P NMR and powder diffraction data can be used to determine the structure of this 136 unique-atom material. The structure has been solved using a combination of simulated annealing and Rietveld refinement performed simultaneously on X-ray and neutron diffraction data. Despite the close to cubic metric symmetry of the material, we show how its true orthorhombic structure (space group Pbca) can be refined to a high degree of precision.
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