Structures and Properties of NbOF3 and TaOF3 — with a Remark to the O/F Ordering in the SnF4 Type Structure

✍ Scribed by J. Köhler; A. Simon; L. van Wüllen; S. Cordier; T. Roisnel; M. Poulain; M. Somer

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: German
• Weight: 180 KB
• Volume: 628
• Category: Article
• ISSN: 0372-7874
• DOI: 10.1002/1521-3749(200212)628:12<2683::aid-zaac2683>3.0.co;2-e

✦ Synopsis

Powder samples of NbOF 3 und TaOF 3 were prepared by heating mixtures of NbO 2 F and NbF 5 or TaO 2 F and TaF 5 , respectively, in the corresponding stoichiometric ratio in platinum crucibles under argon atmosphere (180Ϫ220°C). Both oxide fluorides are coulourless with a slight greyish tinge. They are sensitive to moisture and decompose in air at room temperature within hours.

Both, NbOF 3 and TaOF 3 crystallize as a variant of the SnF 4 type structure, space group I4/mmm. The structures have been refined from X-ray powder diffraction data using the Rietveld method (a ϭ 3.9675(1) A ˚, c ϭ 8.4033(1) A ˚, R B ϭ 3.60%, R p ϭ 4.58 % forNbOF 3