Luminescence and intramolecular energy-transfer processes in isomeric cyano-bridged Rhenium(I)-Rhenium(I) and Rhenium(I)-Ruthenium(II)-Rhenium(I) polypyridyl complexes

Journal Article · Wed Dec 09 00:00:00 EST 1992 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00051a016· OSTI ID:6836842

Kalyanasundaram, K; Graetzel, M; Nazeeruddin, M K ^[1]

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1. Institut de Chimie Physique, Lausanne (Switzerland)

Mixed-metal and homometal cyano-bridged polypyridyl complexes of Re(I) and Ru(II) such as [(CO)[sub 3](bpy)Re-CN-Re(bpy)(CO)[sub 3]][sup +], [(CO)[sub 3](bpy)Re-NC-Ru(bpy)[sub 2]-CN-Re(bpy)(CO)[sub 3]][sup 2+], and [(CO)[sub 3](bpy)Re-CN-Ru(dcbpy)[sub 2]-NC-Re(bpy)(CO)[sub 3]][sup 2+] (bpy = 2,2[prime]-bipyridine and dcbpy = 4,4[prime]-dicarboxy-2,2[prime]-bipyridine) have been synthesized. Their spectroscopic, redox, and photophysical properties are reported. The lowest energy CT excited state in these complexes (Re-bpy or Ru-bpy CT) is emissive in fluid solutions. In the trinuclear complexes, intense absorption in the infrared region corresponding to intervalence (IT) transitions are reported in the CT excited state and partially oxidized species. Luminescence and redox properties have been used to assess intramolecular energy/electron-transfer processes between the terminal Re(I)-polypyridyl and central Ru(II)-polypyridyl units. The intervalence transitions and the excitation spectra for the Ru-based emission suggest efficient occurrence of energy transfer from the CT excited state of the Re-based chromophore to the Ru-based unit in both complexes [(CO)[sub 3](bpy)Re-NC-Ru(bpy)[sub 2]-CN-Re(bpy)(CO)[sub 3]][sup 2+] and [(CO)[sub 3](bpy)Re-CN-Ru(dcbpy)[sub 2]-NC-Re(bpy)(CO)[sub 3]][sup 2+]. A comparison is made between the N- and C-bonded isomers and also between Re-Ru-Re- and Ru-Ru-Ru-polypyridyl trinuclear complexes.

• OSTI ID: 6836842
• Journal Information: Inorganic Chemistry; (United States), Vol. 31:25; ISSN 0020-1669
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
RHENIUM COMPLEXES
CHEMICAL PREPARATION
LUMINESCENCE
RUTHENIUM COMPLEXES
ABSORPTION SPECTROSCOPY
ELECTRON TRANSFER
EMISSION SPECTRA
ENERGY TRANSFER
EXCITED STATES
ISOMERIZATION
LIGANDS
PHOTOLUMINESCENCE
PYRIDINES
REDOX POTENTIAL
SPECTROSCOPY
STABILITY
AZINES
CHEMICAL REACTIONS
COMPLEXES
ENERGY LEVELS
HETEROCYCLIC COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
SPECTRA
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties