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Updated: Jun 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
Construction of an organic crystal structural model based on combined electron and powder X-ray diffraction data and
Jinsong Wu1, Yong Sheng Zhao, Hefei Hu
1Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA. jinsong-wu@northwestern.edu
Abstract:
The structure of an organic dye 1,5-diaminoanthraquinone (DAAQ) nanowire was studied by both electron diffraction and X-ray powder diffraction. The unit cell of the crystal was determined from a series of tilted selected area electron diffraction patterns (monoclinic: a=3.78 Å, b=9.73 Å, c=15.01 Å and β=82.4 °). By using precession electron diffraction, the following extinction conditions were determined, 0k0: k=2n and 00l: l=2n, which give the space group as P2₁/C (no. 14). The powder charge flipping algorithm was applied to resolve the phase problem and the structural model of the DAAQ crystal was built.
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