Spectroscopic and Magnetic Properties of Coordination Complexes

Spectroscopic and Magnetic Properties of Coordination Complexes A. Monomers 

There are also charge-transfer characteristics within the electronic transitions between the spin-orbit states of the pentaammine complexes. This is evidenced by order of magnitude increases in the intensities of these transitions when an ammine or aqua ligand is replaced by a 77-base (e.g., Cl ) or a 7r-acid (e.g., N heterocycle) (67). 

Detailed studies of the solvent dependencies of the charge-transfer transitions in the UV/Vis region of [Os(NH3)5(Mepz)]3+ and a variety of 

When the symmetry is reduced by replacement of a bpy ligand by another bidentate, the symmetry restrictions are relaxed and the initially formed excited state is expected to be localized (600, 601). The rates of nonradiative decay of a large range of Os(II)-polypyridine have been calculated successfully in terms of a modified energy gap law in which low-frequency modes are explicitly considered (148). 

The charge transfer that occurs on photoexcitation changes the pAa values of substituents on bpy or related ligands. Because the substituents become more basic as a result of the MLCT nature of the triplet states, excited-state proton transfers can occur. There have been many studies of such reactions of Ru complexes, but few on analogous Os complexes until recently (233). 

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