abstract
In the present study, four new Co(II/III) metal complexes, [Co(pheo)(3)]S4O6 center dot 2H(2)O (1), [Co(Phen)(3)] S4O6 center dot 7H(2)O (2), [CO(phen)(3)](2)(S4O6)(3)center dot 6.5H(2)O (3) and [Co(phen)(3)]S2O3 center dot 9H(2)O (4), have been synthesized and characterized by elemental analysis, TGA and various spectroscopic techniques. In the case of 1 and 2, an unexpected redox reaction took place and the complexes formed are different in terms of their water of crystallization. The structures of 1-3 have been determined by single crystal X-ray crystallography. Complex salts 1-3 crystallize in the orthorhombic (Pbca). triclinic (P (1) over bar) and monoclinic (P2(1)/c) crystal systems, respectively. Their X-ray crystal structure determination revealed the presence of non-covalent cation-to-anion (C-H center dot center dot center dot O-anion hydrogen bonds), anion-to-cation (anion center dot center dot center dot pi interactions) and cation-to-cation (C-H center dot center dot center dot pi and pi center dot center dot center dot pi stacking interactions) interactions. Interestingly, a detailed packing analysis has shown the presence of rare chains of cyclic water hexamers (chair form) and tetramers, stabilized by O-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bond interactions in the supramolecular complex [Co(phen)31 S4O6 center dot 7H(2)O (2). (C) 2012 Elsevier Ltd. All rights reserved.
keywords
ORGANIC SUPRAMOLECULAR COMPLEX; HYDROGEN-BOND PATTERNS; GRAPH-SET ANALYSIS; SPECTROSCOPIC PROPERTIES; (H2O)(10) CLUSTER; SOLID-STATE; COORDINATION; FRAMEWORK; LIQUID; ICE
subject category
Chemistry; Crystallography
authors
Sharma, RP; Singh, A; Venugopalan, P; Brandao, P; Felix, V
our authors
Paula Cristina Ferreira da Silva Brandão
Assistant Researcher
Vítor Félix
Associate Professor with Aggregationacknowledgements
The authors gratefully acknowledge the financial support of CSIR vide Grant No. 09/135/(0594)/ 2010/EMR-I.