The crystal structure determinations and refinements of K2S2O7, KNaS2O7 and Na2S2O7 from X-ray powder and single crystal diffraction data

✍ Scribed by Kenny Ståhl; Tonci Balic-Zunic; Fransisco da Silva; K. Michael Eriksen; Rolf W. Berg; Rasmus Fehrmann

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 367 KB
• Volume: 178
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2005.03.022

✦ Synopsis

A; a ¼ 116:779ð2Þ; b ¼ 96:089ð3Þ; g ¼ 84:000ð3Þ1; R F ¼ 0:033: The disulphate anions are essentially eclipsed. All three structures can be described as dichromate-like, where the alkali cations coordinate oxygens of the isolated disulphate groups in three-dimensional networks. The K-O and Na-O coordinations were determined from electron density topology and coordination geometry. The three structures have a cationdisulphate chain in common. In K 2 S 2 O 7 and Na 2 S 2 O 7 the neighbouring chains are antiparallel, while in KNaS 2 O 7 the chains are parallel. The differences between the K 2 S 2 O 7 and Na 2 S 2 O 7 structures, with double-, respectively single-sided chain connections and straight, respectively, corrugated structural layers can be understood in terms of the differences in size and coordinating ability of the cations.