component (t = 4.7 ns). This rvalue is consistent with previous (room temperature) estimates of donor-acceptor center to center distance of 25 A. The most important result is that the simplified kinetics at room temperature argue that any structural states of the complex which arc trapped at 77 K are largely equilibrated at 300 K within 5 ns. This result suggests that motion at the cytc/ccp interface can be quite rapid and offers experimental support for the rapid restricted dimensional diffusion model of the eyie-eep complex suggested by Brownian dynamics.8 With this information now available, more detailed insight into the nature of the binding sites in principle could be obtained by comparing the decay distributions for the native systems with those for site-specific mutants.9'10 Such studies are in progress.

We present bulk magnetic susceptibility, specific heat, transport, NMR, and NQR results of the perovskite compound CaCu 3 Ru 4 O 12 . The data consistently describe a metallic state with a moderately enhanced Sommerfeld coefficient of ␥ =92 mJ/ mol K 2 and a spin-fluctuation temperature of about 180 K. The heat capacity below 2 K shows a logarithmic increase providing evidence for non-Fermi-liquid ͑NFL͒ behavior in CaCu 3 Ru 4 O 12 . Further signatures of NFL properties are found in NQR measurements revealing deviations from a Korringa behavior of the spin-lattice relaxation rate. The results are discussed with respect to heavyfermion and NFL properties in other transition-metal compounds and traditional f-electron systems.

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We report on NMR studies of the quasi-one-dimensional antiferromagnetic S =1/ 2 chain cuprate LiCuVO 4 , focusing on the high-field spin-modulated phase observed recently in applied magnetic fields H Ͼ H c2 ͑ 0 H c2 Ϸ 7.5 T͒. The NMR spectra of 7 Li and 51 V around the transition from the ordered to the paramagnetic state were measured. It is shown that the spin-modulated magnetic structure forms with ferromagnetic interactions between spins of neighboring chains within the ab plane at low temperatures 0.6 K Ͻ T Ͻ T N . The best fit provides evidence that the mutual orientation between spins of neighboring ab planes is random. For higher temperatures T N Ͻ T Շ 15 K, short-range magnetic order occurs at least on the characteristic time scale of the NMR experiment.

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