EPR STUDIES ON IRRADIATED GROUP-VI TETRACHALCONIDE IONS

EPR measurements have been made at X-band frequency and at 77 K on gam ma-irradiated glassy solutions of salts of the d(0) chalconide anions MX42- (M = Cr, X = O; M = Mo, X = O or S; M = W, X = O or S). Annealin g of the irradiated solutions revealed broad high-held spectral featur es attributable to one-electron addition to the anions; The exception being WS42-, for which no EPR signal was detectable at 77 k or above. The results point to the added electron being predominantly located on the metal centre (d(1)). The g-shifts are interpreted in terms of a d istorted T-d geometry with a d(x2-y2) configuration. (C) 1998 Elsevier Science Ltd. All rights reserved.