Related Experiment Video
Updated: Aug 7, 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
Decomposition of silver carbonate; the crystal structure of two high-temperature modifications of Ag(2)CO(3)
P Norby1, R Dinnebier, A N Fitch
1Department of Chemistry, University of Oslo, Norway. poul.norby@kjemi.uio.no
Abstract:
High-resolution powder diffraction was used to study the thermal transformation of silver carbonate. A sample of Ag(2)CO(3) was heated in a capillary under 4.5 atm CO(2) pressure. The decomposition temperature of silver carbonate to silver oxide is thereby increased, allowing high-resolution synchrotron X-ray powder diffraction patterns of the two high-temperature phases of Ag(2)CO(3) to be collected. The structure of the low-temperature (lt) phase was confirmed, and the structures of the two high-temperature phases were determined by direct methods and refined using the Rietveld method: lt-Ag(2)CO(3) (295 K) P2(1)/m, z = 2, a = 4.8521(2) A, b = 9.5489(4) A, c = 3.2536(1) A, beta = 91.9713(3) degrees; beta-Ag(2)CO(3) (453 K) P31c, z = 6, a = 9.1716(4) A, c = 6.5176(3) A; alpha-Ag(2)CO(3) (476 K) P6 macro 2m, z = 3, a = 9.0924(4) A, c = 3.3249(1) A. In addition, thermal expansion properties, anisotropic microstrain distributions, and thermal transformations of the three silver carbonate phases and silver oxide are described.
More Related Videos
Related Concept Videos
Chemical Reactions in Aqueous Solutions
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
Formation of Complex Ions
Precipitation Titration Curve: Analysis
Colloidal precipitates

