ESR spectrum of IO2minus;4

摘要

A paramagnetic species prepared from IOminus;4embedded in solid KBrO4by x irradiation at 26 K is identified as the radicalhyphen;ion IO2minus;4because its spin Hamiltonian is closely analogous that of BrO2minus;4. Labeling with17O shows that IO2minus;4is a sgr; radical with the electron spin located primarily on two oxygens atoms and on the iodine atom, whereas the nuclear quadrupole interaction indicates that the nuclear geometry of IO2minus;4resembles that of the parent IOminus;4. Due to the large hyperfine splitting (sim;4 GHz) only one allowed ESR transition and an NMR transition appear at 9.3 GHz, whereas the six allowed ESR transitions are all observed at 35 GHz. A similar signal observed in x irradiated KIO4is also assigned to IO2minus;4.