New zinc-glycine-iodide complexes as a product of equilibrium and non-equilibrium crystallization in the Gly – ZnI2 – H2O system

0459583 - ÚACH 2017 RIV NL eng J - Článek v odborném periodiku
Tepavitcharova, S. - Havlíček, D. - Matulková, I. - Rabadjieva, D. - Gergulova, R. - Plocek, Jiří - Němec, I. - Císařová, I.
New zinc-glycine-iodide complexes as a product of equilibrium and non-equilibrium crystallization in the Gly – ZnI2 – H2O system.
Journal of Molecular Structure. Roč. 1120, SEP (2016), s. 42-49. ISSN 0022-2860. E-ISSN 1872-8014
Institucionální podpora: RVO:61388980
Klíčová slova: [Zn(gly)I2], [Zn(gly)2I2] * [Zn3(H2O)4(μ-gly)2I6] * Crystal structure * Vibrational spectra * Thermal behaviour
Kód oboru RIV: CA - Anorganická chemie
Impakt faktor: 1.753, rok: 2016

Equilibrium crystallization of two anhydrous complex compounds, [Zn(gly)2I2] and [Zn(gly)I2], and non-equilibrium crystallization of the [Zn3(H2O)4(μ-gly)2I6] complex have been observed in the Gly - ZnI2 - H2O system at 25°C. Different mixed zinc-glycine-iodide-aqua complexes exist in the studied solutions and those with the highest activity are responsible for the crystallization process. The stable [ZnI2O2(2Gly)]0 complexes are responsible for the large equilibrium crystallization field of the compound [Zn(gly)2I2] (monoclinic system, C2/c space group), in whose crystal structure they are incorporated as discrete distorted electroneutral tetrahedra. In zinc-iodide solutions with a low water activity it is more probable that the glycine zwitterions act as bidentate ligands and form polynuclear complexes. We assume the [ZnI2O2(2/2Gly)]0 infinite chains build the compound [Zn(gly)I2], for which we have found a narrow equilibrium crystallization field. We have failed to describe the crystal structure of this compound because of its limited stability in the air. Non-equilibrium crystallization of [Zn3(H2O)4(μ-gly)2I6] (triclinic system, P-1 space group) was demonstrated, with crystal structure built by trinuclear complexes [ZnI3O(1/2Gly)] [ZnO4(4H2O)O2(2/2Gly)(trans)][ZnI3O(1/2Gly)]. The FTIR and Raman spectra and also the thermal behaviour of the three compounds were discussed.
Trvalý link: http://hdl.handle.net/11104/0259765