INTRAMOLECULAR AND REORIENTATION DYNAMICS OF INE)-3,6-DI-TERT-BUTYL-4,5-DIMETHOXY-O-SEMIQUINONE COMPLEX OF COPPER(I) IN VISCOUS MEDIA

Two simultaneous dynamical processes are studied in solutions of varyi ng viscosity by using the EPR linewidth data of a Cu(I) o-semiquinone complex with two triphenylphosphine ligands (PPh(3)), i.e. the overall reorientation (tumbling) of the complex and intramolecular exchange o f the PPh(3) ligands in the coordination sphere of the complex, It is shown that for fast motion the line broadening of the hyperfine compon ents is due to both modulation of the anisotropic magnetic parameters by rotational diffusion and to modulation of the isotropic part of the P-31 hyperfine interaction by intramolecular exchange. The intramolec ular dynamics of the coordination sphere appears to be dependent on th e solvent dynamics.