ChemInform Abstract: The Polar [WO₂F₄]^2‐ Anion in the Solid State.

Abstract

structure structure (solids and liquids) D 2000 -009The Polar [WO 2 F 4 ] 2− Anion in the Solid State.-The crystal structures of the compounds (IV) and (V) are solved by single-crystal X-ray analysis. Compound (IV) crystallizes in the tetragonal space group I4 1 22 with Z = 4. Its structure is built from [Cu(py) 4 (WO 2 F 4 ) 2 ] 2− anions hydrogen bonded to pyridinium (pyH + ) cations. Compound (V) is obtained in two polymorphic forms in an overall yield of 60%. Polymorph A crystallizes in the tetragonal space group I4/mcm with Z = 4, whereas polymorph B crystallizes in the tetragonal space group P4/mmm with Z = 1. The copper cations in (V) are bridged by four pyrazine ligands to form [Cu(pyz) 4/2 ] 2n+ n infinite square nets in the (001) plane. The axial copper positions are coordinated by [WO 2 F 4 ] 2− anions, which link the infinite nets together in the c direction. The resulting three-dimensional structure contains channels which are filled with H 2 O and pyrazine solvent molecules. The [WO 2 F 4 ] 2− anion has cis-configuration in all complexes. -(HEIER, KEVIN R.; NORQUIST, ALEXANDER J.; HALASYAMANI, P. SHIV; DUARTE, ANGEL; STERN, CHARLOTTE L.; POEPPELMEIER, KENNETH R.; Inorg. Chem. 38 (1999) 4, 762-767; Dep.

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