ESR Studies on Platinum Uracil Blue

Abstract

Abstract ESR spectra of platinum uracil “blue” are discussed. Two main types o f paramagnetic species have been found, one of which can be explained by assuming an unpaired electron spin delocalized over dz²-orbitals of two equivalent Pt centers, the other one is attributed to a more localized d7 Pt(III) center. In both cases the hyperfine structure suggests an additional smaller probability density of the unpaired electron at one adjacent platinum center. The smallest possible oligomers to realize this facts are tetramers in the first case and dimers in the latter one.