Fluoro- and oxo-fluorozirconates

Abstract

The preparations of (BH 2) [ZrF 6]. mH 2O, where B = ethylenediamine (m=0) and biguanide (m=1), (BH) 2 [ZrF 6].nH 2O, where B = guanidine (n=1), pyridine (n=0), (BH) [ZrF 5].H 2O, where B = α β - and γ -picoline, (BH 2) [ZrOF 3] 2.xH 2O, where B = ethylenediamine (x=5), propylene-1,2-diamine (x=3), N,N‵-dimethylethylenediamine (x=3), M I[ZrOF 3].1.5 H 2O, where M I = alkali metals, (N 2H 5) [Zr 2O 2F 5].4H 2O and (BH 2) [ZrOF 4], where B = 1,10-phenanthroline and 2,2‵-bipyridyl are described. The compounds were characterised by chemical analysis, TGA, IR spectroscopy and x-ray powder photography. (pyH) 2[ZrF 6] (py = pyridine) is unstable and undergoes slow decomposition on keeping in air. On isothermal heating at 120°C it yields (py H) [ZrF 5]. At 180°C (α -pic H) [ZrF 5].H 2O(α -pic = α -picoline) yields (α - pic H)[Zr 2F 9]. K[ZrOF 3].1.5 H 2O yields K[ZrOF 3].O.5H 2O and the anhydrous compound successively at 130°C and 225°C. The corresponding anhydrous cesium compound is produced at 220°C. IR spectra suggest the presence of Zr-O-Zr chains in the oxofluoro-compounds. From the various types of studies it appears that the oxofluorozirconates contain only a fraction of water as Zr-OH group.