Crystal Structure of Pyridinium Periodate

Abstract

The crystal structure of the room-temperature ferroelectric phase of pyridinium periodate [C 6 H 5 NH] + [IO 4 ] - has been determined by X-ray diffraction as orthorhombic, space group Cmc2 i with a = 8.347(2), b = 7.270(2), c = 12.732(3) Å and Z = 4. It was refined to R1 =0.0281 wR2 = 0.0762 for 389 absorption-corrected reflections. The structure comprises isolated IO 4 tetrahedra linked together by disordered pyridinium cations involved in a network of bifurcated hydrogen bonds. The average I-O distance is found to be 1.75(1) Å.