ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Two organically templated metal sulfate/selenate: IR spectroscopy, crystal structure, and thermal behaviour

Marwa Abid Derbel, Ines Kadri, Houcine Naïli, and Walid Rekik

Université de Sfax, Sfax, Tunisia

E-mail: walid.rekik@fss.usf.tn

Abstract: Two organically templated transition metal sulfate/selenate compounds with following formula (C₆H₁₄N₂)[Co(H₂O)₆](S_0.83Se_0.17O₄)₂ (1) and (C₄H₁₂N₂)[Cu(H₂O)₄(S_0.39Se_0.61O₄)₂]·2H₂O (2) have been synthesized and crystallographically characterized. Both coordination compounds adopt the monoclinic symmetry, P2₁/c space group with the following unit-cell parameters: a = 12.0669(13) Å; b = 12.1768(11) Å; c = 12.1158(12) Å; β = 104.023(4)° and Z = 4 for (1) and P2₁/n space group with the following unit-cell parameters: a = 6.9783(2) Å; b = 11.7101(4) Å; c = 10.6238(3) Å; β = 104.431(2)° and Z = 2 for (2). While compound (1) is fully supramolecular with a crystal structure consisting of metallic cations octahedrally coordinated by six water molecules [Co(H₂O)₆]²⁺, dabcodiium and sulfate/selenate (S_0.39Se_0.61O₄)²⁻ anions which are linked via Ow–H…O and N–H…O Hydrogen bonds, compound (2) exhibits a beginning of condensation and its atomic arrangement is built from anionic entity [Cu(H₂O)₄(S_0.39Se_0.61O₄)₂]²⁻ and piperazinediium cations (C₄H₁₂N₂)²⁺ linked together by hydrogen bonds only. Through this work, we can conclude that the partial substitution of sulfur by selenium does not affect the atomic arrangement and that the type of structure adopted by the new solid solution is that of the pure sulfate or selenate-based compound according to the rate of substitution. The thermal decomposition of both precursors proceeds through several stages giving rise to the cobalt oxide and to the copper oxyselenate as final product for (1) and (2), respectively.

Keywords: Partial substitution sulfate/selenate ; Crystal structure ; Thermal decomposition ; Supramolecular chemistry ; Coordination compounds 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-018-0503-x

Chemical Papers 72 (10) 2503–2512 (2018)