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Updated: Feb 10, 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
Crystal structure of calcium perchlorate anhydrate, Ca(ClO4)2, from laboratory powder X-ray diffraction data
Dongmin Lee1, Hyeri Bu1, Dohwan Kim1
1Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea.
Abstract:
The crystal structure of calcium perchlorate anhydrate was determined from laboratory X-ray powder diffraction data. The title compound was obtained by heating hydrated calcium perchlorate [Ca(ClO4)2·xH2O] at 623 K in air for 12 h. It crystallizes in the ortho-rhom-bic space group Pbca and is isotypic with Ca(AlD4)2. The asymmetric unit contains one Ca, two Cl and eight O sites, all on general sites (Wyckoff position 8c). The crystal structure consists of isolated ClO4- tetra-hedra and Ca2+ cations. The Ca2+ cation is coordinated by eight O atoms of eight symmetry-related ClO4- tetra-hedra within a distorted square-anti-prismatic environment.
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