abstract
The asymmetric unit of the title compound, C3H4N4O2 center dot-0.5H(2)O, comprises two whole molecules of 5-amino-1H-1,2,4-triazole-3-carboxylic acid in its zwitterionic form (proton transfer occurs from the carboxylic acid group to the N heteroatom at position 1), plus one water molecule of crystallization. The organic moieties are disposed into supramolecular layers linked by N-H center dot center dot center dot O and N-H center dot center dot center dot N hydrogen bonds parallel to the bc plane. Additional O-H center dot center dot center dot O and N-H center dot center dot center dot O hydrogen bonds involving the water molecules and the organic molecules lead to the formation of double-deck supramolecular arrangements which are interconnected along the a axis via pi-pi stacking [centroid-centroid distance = 3.507 (3) angstrom].
keywords
HYDROTHERMAL SYNTHESIS; COORDINATION POLYMERS; ACID; FRAMEWORK
subject category
Crystallography
authors
Fernandes, JA; Liu, B; Tome, JPC; Cunha-Silva, L; Paz, FAA
our authors
Projects
acknowledgements
We are grateful to the Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) for their general financial support under the R&D projects PTDC/QUI-QUI/098098/2008 and PTDC/CTM/100357/2008, and for the post-doctoral research grants, Nos. SFRH/BPD/63736/2009 (to JAF) and SFRH/BPD/47566/2008 (to BL). Thanks are also due to FCT for specific funding toward the purchase of the single-crystal diffractometer.