The Structure of a Complex Open-framework Germanate Obtained by Combining Powder Charge-Flipping and Simulated Annealing
2012 (English)In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 12, no 10, 4853-4860 p.Article in journal (Refereed) Published
A novel open-framework germanate SU-74 containing intersecting 10- and 12-ring channels was prepared by hydrothermal synthesis using 2-methylpentamethylenediamine (MPMD) or 1-(2-aminoethyl)piperazine (AEP) as the organic structure directing agent (SDA). The framework structure of SU-74-MPMD was solved from X-ray powder diffraction (XRPD) data using powder charge-flipping (pCF). The guest species H2MPMD2+, NH4+ cations and water molecules were located in the voids using real-space simulated annealing. SU-74-MPMD contains 51 non-hydrogen atoms in its asymmetric unit and is one of the most complex framework structures solved by XRPD. The structure of SU-74-AEP was solved by single crystal synchrotron X-ray diffraction. SU-74-MPMD and SU-74-AEP have the same framework structure. The location of the NH4+ cations in both structures is similar, while the positions of the SDAs in the pores are different. SU-74 follows the fcu-11-P21/c net. The underlying topology of SU-74 is compared to those of other Ge10 structures containing additional GeO4 tetrahedra. The presence of additional tetrahedra can significantly affect the framework topology through the addition of edges between the Ge10 nodes.
Place, publisher, year, edition, pages
2012. Vol. 12, no 10, 4853-4860 p.
Research subject Structural Chemistry
IdentifiersURN: urn:nbn:se:su:diva-75921DOI: 10.1021/cg300647sISI: 000309493300025OAI: oai:DiVA.org:su-75921DiVA: diva2:524772
FunderSwedish Research CouncilKnut and Alice Wallenberg Foundation