The nuclear quadrupole resonance of dibromoiodate ions

The NQR spectra due to 81Br and 127I in potassium dibromoiodate and its monohydrate were observed, and the Zeeman effect of 81Br NQR in the monohydrate was examined. The resonance lines indicate that both compounds have two kinds of dibromoiodate ions and that these ions in the anhydride are slightly asymmetric, while those in the monohydrate are symmetric. The difference in frequency between the two resonance lines due to each resonant nucleus in the monohydrate is explained in terms of the I...Br intermolecular interaction. The charge distributions in both compounds were evaluated to be about -0.6l and 0.2l on the terminal and central atoms respectively. (auth.)