| Abstract
| - Ground and excited state properties of the new complexes Re(CO)3(2,2‘-biquinoline)L2*, L2 = pyrazine or 4,4‘-bipyridine, and Re(CO)3(2,2‘-bipy)(2-pyrazinecarboxylate), shown, were investigated. One component of the luminescence was related to metal to ligand charge transfer excited states. CuCl2 formed ground state adducts with these complexes and quenched the luminescence via energy transfer with a complex rate.
- Ground and excited state properties of the newly prepared complexes Re(CO)3(2,2‘-biquinoline)LS+, LS = pyrazine or 4,4‘-bipyridine, and Re(CO)3(2,2‘-bipy)(2-pyrazinecarboxylate)were investigated by steady state and time-resolved spectroscopy. The X-ray structure ofthe latter compound showed that the spectator ligand 2-pyrazinecarboxylate is coordinatedthrough the carboxylate group to Re(I). A component of the complexes' luminescence wasassociated with long-lived Re to ligand, 2,2‘-biquinoline or 2,2‘-bipy, charge transfer, whilea fast component of the emission was associated with intraligand excited states. Quenchingof the luminescence by CuCl2 involved energy transfer via dynamic and static mechanisms.The complexes in their excited states were reduced by 2,2‘,2‘ ‘-nitrilotriethanol with theformation of Re(I) ligand-radical species. Similar products were generated by the pulseradiolytic reduction of the complexes. The photochemical properties of the 2,2‘-biquinolinecomplexes and Re(CO)3(1,10-phen)4-nitrobenzoate are compared, and the mechanisms oftheir photochemical reactions are discussed.
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