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Updated: Aug 3, 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
Structure determination of phi-Bi8Pb5O17 by electron and powder X-ray diffraction
Abstract:
The triclinic crystal structure of phi-Bi8Pb5O17, a ionic fast conductor material, has been determined by the synergy of both electron and powder X-ray crystallography. The heavy atom positions were found by direct methods on electron diffraction data and the structure was completed by iterative use of a priori information in direct methods and difference Fourier maps on both types of data. Structure refinement was performed by the Rietveld method on powder X-ray data. The results suggest that phi-Bi8Pb5O17 is an ordered phase, with Bi and Pb atoms occupying different sites of the lattice, at variance with the other structural phases known for similar composition in the Bi-Pb-O phase diagram, which are solid solutions characterised by a wide compositional range.
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