Intramolecular electron transfer on the vibrational timescale in mixed valence ruthenium clusters

• Autorzy: Imai, N. , Hamaguchi, T. , Yamaguchi, T. , Ito, T.
• Języki publikacji: EN

Abstrakty

EN

The thermodynamic stability of the mixed valence (one electron reduced) state between linked Ru3 units was studied by means of electrochemistry for the series of the ligand bridged triruthenium cluster dimers, [Ru3(ž3-O)(ž-CH3CO2)6(CO)(L)(ž-BL)Ru3(ž3-O)-(ž-CH3CO2)6(CO)(L)] (BL = pyrazine: L = 4-dimethyl-aminopyridine (dmap) (1a), pyridine (py) (1b), 4-cyanopyridine (cpy) (1c), 1-azabicyclo[2.2.2]octane (1d); BL = 4,4'-bipyridine: L = dmap (2a), py (2b), cpy (2c); BL = 2,7-diazapyrene: L = dmap (3a); BL = 1,4-diazabicyclo-[2.2.2]octane: L = dmap (4a), py (4b), cpy (4c)). The mixed valence states undergoing rapid intramolecular electron transfers were observed by IR spectroelectrochemistry. By simulating dynamical effects on the observed ?(CO) absorption bandshapes, the rate constants, ke, for electron transfer in the mixed valence states of 1a, 1b, 1c and 1d were estimated to be 9 x 1011 s-1 (at room temperature (rt)), 5 x 1011 s-1 (at rt), ca. 1 x 1011 s-1 (at rt), and 1 x 1012 s-1 (at -18°C), respectively. Possible applications of this approach to asymmetric mixed valence systems were discussed.

Słowa kluczowe

EN

ruthenium clusters; electron transfer; mixed valence

• Czasopismo: Materials Science
• Rocznik: 2003
• Tom: Vol. 21, No. 2
• Strony: 207-214
• Opis fizyczny: Bibliogr. 6 poz.,

Twórcy

autor

Imai, N.

• Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Japan

autor

Hamaguchi, T.

• Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Japan

autor

Yamaguchi, T.

• Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Japan

autor

Ito, T.

• Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Japan,

Bibliografia

• [1] Ito T., Hamaguchi T., Nagino H., Yamaguchi T., Washington J., Kubiak C.P., Science, 277 (1997), 660.
• [2] Ito T., Hamaguchi T., Nagino H., Yamaguchi T., Kido H., Zavarine I .S., Richmond T., Washington J., Kubiak C. P., J. Am. Chem. Soc., 121 (1999), 4625.
• [3] Ito T., Yamaguchi T., Kubiak C.P., Macromol. Symp., 156 (2000), 269.
• [4] Yamaguchi T., Imai N., Ito T., Kubiak C.P., Bull Chem. Soc. Jpn., 73 (2000), 1205.
• [5] unpublised result.
• [6] Grevels F.-W, Kerpen K., Klotzbucher W.E., McClung R.E.D., Rüssel G., Viotte M., Schaffner K., J. Am. Chem. Soc., 120 (1998), 10423.