The first crystal structure analysis of an iodyl compound

Single crystals of (IO2)(2)S2O7 were obtained for the first time by reacting iodic acid and oleum at 195 degrees C. According to the results of a X-ray structure determination (monoclinic, P2(1)/a, a = 885.0(2), b = 1037.3(2), c = 915.8(2) pm, beta = 94.75(2)degrees, Z = 4, 1466 diffractometer data, R-1 = 0.033, wR(2) = 0.063), (IO2)(2)S2O7 contains dimeric iodyl cations (IO2)(2)(2+), which are connected by disulfate groups thus forming polymeric strands. Strikingly, the I-O-distances range almost continuously from 174 pm (strong intramolecular bonds) to >300 pm (van der Waals contacts).