IUCr journals

Solving complex open-framework structures from X-ray powder diffraction by direct-space methods using composite building units

J. Appl. Cryst. (2013). 46, 1094-1104 (http://doi.org/nss)

[Germanate] The open-framework structure of germanate SU-66 solved from X-ray powder diffraction using the software FOX. The framework was built by Ge10(O,OH)27 (Ge10) clusters, each consisting of six GeO4 tetrahedra (in green) and four GeO6 octahedra (in red). Additional GeO4 tetrahedra not belonging to any Ge10 clusters are in blue.

Solving structures of complex open-frameworks from powder diffraction is often challenging because of peak overlapping. We show that if the building units can be identified, open-framework structures can be solved ab initio from X-ray powder diffraction data using the parallel tempering algorithm implemented in the software FOX. Infrared spectroscopy was used for the first time to identify the building unit in a novel germanate denoted SU-66. The structure of SU-66, with 55 unique atoms in the asymmetric unit, was solved from in-house X-ray powder diffraction data.

A. K. Inge, H. Fahlquist, T. Willhammar, Y. Huang, L. B. McCusker and X. Zou