PARAMAGNETIC HYPERFINE-STRUCTURE OF IR-193 IN K2IRCL6 DILUTED INTO K2PTCL6

The paramagnetic hyperfine splitting of Ir4+ (5d5) in K2IrCl6 diluted into diamagnetic K2PtCl6 has been observed at 4.2 K and Ir:Pt ratios of 1:10 and 1:25. In the latter case a narrow paramagnetic pattern with a hyperfine coupling constant of A=-13.1(2) mm/s was observed, but both samples also exhibit a single Ir4+ line typical for fast relaxation, either because of macroscopic inhomogeneities in the Ir distribution or because part of the Ir spins are still coupled to nearest Ir neighbours. © 1990 J.C. Baltzer A.G. Scientific Publishing Company.