abstract
The crystalline compounds (Hbipy)(2)[Ge(C(2)O(4))(3)] (1) and (Hphen)(2)[Ge(C(2)O(4))(3)] center dot 2(H(2)O) (2) [Hbipy(+) is the 2,2'-bipyridinium cation (C(10)H(9)N(2)), and Hphen(+) is the 1,10'-phenathrolinium cation (C(12)H(9)N(2))] were isolated from mild hydrothermal syntheses and their structures were elucidated from single-crystal X-ray diffraction. The two compounds were further characterised by vibrational spectroscopy (FT-IR and FT-Raman), thermogravimetric analysis (TGA) and CHN elemental composition. Compounds 1 and 2 comprise the tris(oxalato-O,O')germanate dianion complex, [Ge(C(2)O(4))(3)](2-), which co-crystallises with Hbipy(+) (in 1), or Hphen(+) and water molecules (in 2). In 1, the germanium oxalate anionic complex, [Ge(C(2)O(4))(3)](2-), and the Hbipy(+) organic residues interact mutually via N-H center dot center dot center dot O hydrogen bonding interactions, leading to supramolecular discrete hydrogen-bonded units which are further interconnected via pi-pi stacking. Compound 2, on the other hand, exhibits a more complex hydrogen bonding network due to the presence of the water molecules of crystallisation which, along with pi-pi stacking between neighbouring Hphen(+) residues, mediate the crystal packing. (c) 2008 Elsevier B.V. All rights reserved.
keywords
X-RAY-DIFFRACTION; CAMBRIDGE STRUCTURAL DATABASE; METAL-ORGANIC FRAMEWORK; COORDINATION POLYMERS; SOLID-STATE; CRYSTAL-STRUCTURE; DESIGN; DERIVATIVES; STORAGE
subject category
Chemistry
authors
Cunha-Silva, L; Shi, FN; Paz, FAA; Hardie, MJ; Klinowski, J; Trindade, T; Rocha, J
our authors
Fa-Nian Shi
Researcher
Filipe Alexandre Almeida Paz
Principal Researcher
João Rocha
Full Professor
Tito Trindade
Full professoracknowledgements
We are grateful to FEDER, POCI (Portugal) and to the Portuguese Foundation for Science and Technology (FCT, MCTES) for their general financial support (POCI-PPCDT/ QUI/58377/2004) and also for the postdoctoral grants SFRH/BPD/14410/2003 (to L.C.-S.) and SFRH/ BPD/9309/2002 (to F.-N.S.). We also wish to thank the EPSRC (UK) and the University of Leeds for equipment funding.