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A study was conducted on the interaction of xenon with cryptophane-A in 1,1,2,2-tetrachloroethane-d2 using 129Xe and 1H NMR spectroscopy. The stability of the xenon complex seems to be much greater than that of the previously described xenon complex of alpha-cyclodextrin in water. The findings indicate that the incoming xenon atom must displace the departing one to enter the cryptophane cavity. Moreover, the results suggest that the complexation equilibrium does not involve the empty cryptophane.

Steady-state [super 1]H photo-chemically induced dynamic nuclear polarization (CIDNP) experiments are conducted on deoxygenated aqueous solutions of [[Ru[(phen).sub.3]].sup.2+], [[Ru[(tap).sub.2](phen)].sup.2+], and [[Ru[(tap).sub.3]].sup.2+] (tap = 1,4,5,8-tetraazaphenanthrene, phen = 1,10-phenanthroline) in the presence of guanosine-5'-monophosphate or N-acetyltyrosine. The [super 1]H photo-CIDNP seen for the biomolecules is weak, however, up to 60% polarization enhancement is seen for H-2 and H-7 of the tap ligands, which has shown high unpaired electron density in the vicinity of these atoms in the transient radical pair.

Signal enhancements in the resolved 1H NMR spectrum offer new opportunities for investigating the chemical environment of xenon atoms. Following binding of laser-polarized xenon to molecules of cryptophane-A, selective enhancements of the 1H NMR signals were observed. A theoretical framework was used for the interpretation of experimental results. The results showed that distances reveal structural characteristics of the complex.

Presents information pertaining to Xe and H NMR spectroscopy. Reversibility of the xenon; Information on the xenon complex; Reference to the results.