Synthesis, X-ray crystal structure and thermal decomposition of two peroxovanadium complexes with coordinated ammonia molecules: [{VO(O2)2(NH3)}2{μ-Cu(NH3)4}] and [Zn(NH3)4][VO(O2)2(NH3)]2

The compounds [{VO(O2)2(NH3)}2{μ-Cu(NH3)4}] (1) and [Zn(NH3)4][VO(O2)2(NH3)]2 (2) were prepared and characterized by elemental analysis and infrared spectra. The single crystal X-ray study revealed that the structure of 1 consists of trinuclear complex molecules [(NH3)OV(O2)2{μ-Cu(NH3)4}(O2)2VO(NH3)] with a rare heterobimetalic peroxo bridge: copper(II)–peroxo ligand–vanadium(V). The structure of 2 is composed of tetraamminezinc(II) cations and ammineoxodiperoxovanadate(V) anions. In course of thermal decomposition of 1 performed up to 620 °C, the following intermediate products: [Cu(NH3)2(VO3)2], and subsequently a mixture of V2O5 with monoclinic β-Cu2V2O7, were gradually formed. The final product of decomposition is Cu(VO3)2. The thermal decomposition of 2 is a two-step process. In the first stage, [Zn(NH3)3(VO3)2] as supposed intermediate was formed, which transformed at higher temperatures by release of ammonia molecules to the monoclinic modification of Zn(VO3)2.

Graphical abstractThe compounds [{VO(O2)2(NH3)}2{μ-Cu(NH3)4}] (1) and [Zn(NH3)4][VO(O2)2(NH3)]2 (2) were characterized by infrared spectra and the X-ray structure analysis. Compound 1 consists of trinuclear molecules with rare heterobimetalic peroxo bridge. The final products of the thermal decomposition of 1 and 2 were Cu(VO3)2 and Zn(VO3)2, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slide