Vibrational and electronic spectroscopy of electronically exicted polychromophoric ruthenium(II) complexes

Journal Article · Wed Apr 13 00:00:00 EDT 1994 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00086a015· OSTI ID:7243032

Bignozzi, C A; Argazzi, R; Chiorboli, C; Scandola, F ^[1]; Dyer, R B ^[2]; Schoonover, J R; Meyer, T J ^[3]

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1. Universita di Ferrara (Italy)
2. Los Alamos National Lab., Los Alamos, NM (United States)
3. Univ. of North Carolina, Chapel Hill (United States)

The metal to ligand charge-transfer excited states of the polychromophoric complexes [(NC)-(bpy)[sub 2]Ru[sup II](CN)Ru[sup II](bpy)[sub 2](CN)][sup +], [(NC)(bpy)[sub 2]Ru[sup II](CN)Ru[sup II](phen)[sub 2](CN)][sup +], [(NC)(phen)[sub 2]Ru[sup II](CN)Ru[sup II](bpy)[sub 2](CN)][sup +], [(NC)(bpy)[sub 2]Ru[sup II](CN)Ru[sup II](bpy)[sub 2](NC)Ru[sup II](bpy)[sub 2](CN)][sup 2+], and [NC(bpy)[sub 2]Ru[sup II](CN)Ru[sup II](dcb)[sub 2](NC)Ru(bpy)[sub 2](CN)][sup 2[minus]] (bpy is 2,2[prime]-bipyridine, phen is 1,10-phenanthroline, and dcb is 4,4[prime]-dicarboxy-2,2[prime]-bipyridine) and of model mononuclear complexes have been investigated in CH[sub 3]CN by time-resolved resonance Raman (TR[sup 3]) and transient UV/vis absorption spectroscopy. The observation in the TR[sup 3] spectra of vibrations of a single type of reduced ligand and the cross check obtained by exchanging ligands around the metal centers provide unambiguous evidence for localization of the excited electron on the polypyridine ligand of the N-bonded (to bridging CN[sup [minus]]) chromophore. The presence of excited-state intervalence transfer bands has been inferred by the comparison of the transient absorbance spectra of the polynuclear complexes with the ground-state spectra to reduced and one-electron oxidized forms and with the spectra of the excited mononuclear complexes. These comparisons indicate the presence of distinct Ru(II) and Ru(III) centers in the excited states of the polynuclear complexes.

• DOE Contract Number: FG05-86ER13633
• OSTI ID: 7243032
• Journal Information: Inorganic Chemistry; (United States), Vol. 33:8; ISSN 0020-1669
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
RUTHENIUM COMPLEXES
ABSORPTION SPECTROSCOPY
RAMAN SPECTROSCOPY
BIPYRIDINES
PHENANTHROLINES
VALENCE
VIBRATIONAL STATES
AROMATICS
AZAARENES
AZINES
COMPLEXES
ENERGY LEVELS
EXCITED STATES
HETEROCYCLIC COMPOUNDS
LASER SPECTROSCOPY
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PYRIDINES
SPECTROSCOPY
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties