ZEOLITE-ENTRAPPED RUTHENIUM(II) COMPLEXES WITH BIPYRIDINE AND RELATEDLIGANDS - ELIMINATION OF LIGAND-FIELD-STATE DEACTIVATION AND INCREASEIN (3)MLCT STATE LIFETIMES
K. Maruszewski et al., ZEOLITE-ENTRAPPED RUTHENIUM(II) COMPLEXES WITH BIPYRIDINE AND RELATEDLIGANDS - ELIMINATION OF LIGAND-FIELD-STATE DEACTIVATION AND INCREASEIN (3)MLCT STATE LIFETIMES, Journal of the American Chemical Society, 115(18), 1993, pp. 8345-8350
Several homoleptic and bis-heteroleptic tris-ligated polypyridine comp
lexes of Ru(II) have been prepared in the zeolite Y supercages. Ru(L)n
(L')3-n-Y (where n = 0, 1, 2, 3 and L, L' = bpy, dmb, mmb, and bpz) co
mplexes have been investigated by electronic absorption, electronic em
ission, resonance Raman, and time-resolved resonance Raman spectroscop
ies. Excited-state lifetimes of the entrapped complexes have been meas
ured and their temperature dependence established. While entrapment of
the complexes in the zeolite matrix introduces no major modifications
in structure or electron distribution, it does induce changes in the
efficiency of various excited state energy dissipation pathways, the m
ajor effect being an increase in the energy of the metal-centered dd e
xcited states which leads to elimination of one of the major decay and
decomposition pathways.