Investigation of EFG Parameters at the Halogen Site in XO3 and XO3 2⊝ Radicals (X = Cl, Br) in Certain Inorganic Solids

Abstract

Electric field gradients at the halogen site in XO 3 and XO 3 2⊝ radicals (X = Cl, Br), formed by the γ-irradiation of single crystals of NaClO3 , KClO3 , KBrO 3 and Sr(BrO3)2 · H20 have been evaluated by MO calculations using the CNDO/2 method. The symmetry of the XO 3 radicals isassumed to be that of XO3 ⊝ ions which have C3v symmetry, whereas XO3 2⊝ radicals are assumed to have CS symmetry with one X -O bond distance being stretched due to the excess electron. The results are in good agreement with the experimental values deduced from published ESR studies on these single crystals.