Photoinduced energy transfer in multinuclear transition-metal complexes. Reversible and irreversible energy flow between charge-transfer and ligand field excited states of cyanide-bridged ruthenium(II)-chromium(III) and ruthenium(II)-rhodium(III) complexes

Journal Article · Wed Nov 21 04:00:00 EST 1990 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00180a025· OSTI ID:5233841

Lei, Yabin; Buranda, T; Endicott, J F ^[1]

---

1. Wayne State Univ., Detroit, MI (USA)

Excited-state relaxation pathways have been examined for some bi- and trinuclear transition-metal complexes containing the Ru(bpy){sub 2}{sup 2+} chromophore linked (or metalated) through cyanide to an amine chromium(III) or rhodium(III) complex. The ({sup 3}CT)Ru(bpy){sub 2}{sup 2+} absorption and emission maxima and the Ru(III)-(II) reduction potentials all increase in energy with metalation. In most instances energy migration from the initially excited ruthenium center to the acceptor metal centers occurred in discrete steps analogous to elementary chemical reactions between independent molecular species.The migration of energy was manifested by quenching of the ({sup 3}CT)Ru donor emission. This was sometimes accompanied either by ({sup 2}E)Cr(III) phosphorescence emission in the chromium metalates or by the growth of a metal-to-metal charge-transfer absorption in a rhodium metalate. Picosecond flash photolysis has been used to observe the equilibration (in about 1 ns) between the ({sup 3}CT)Ru(bpy){sub 2}{sup 2+} and the triplet ligand field excited states of Rh(NH{sub 3}){sub 5}{sup 3+}.

• OSTI ID: 5233841
• Journal Information: Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 112:24; ISSN 0002-7863; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
CHEMICAL REACTIONS
CHROMIUM COMPLEXES
COMPLEXES
CYANIDES
DATA
ENERGY LEVELS
ENERGY TRANSFER
EXCITED STATES
EXPERIMENTAL DATA
INFORMATION
MEASURING METHODS
NUMERICAL DATA
PHOTOCHEMICAL REACTIONS
RHODIUM COMPLEXES
RUTHENIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES