Picosecond infared study of ultrafast electron transfer and vibrational energy relaxation in a mixed-valent ruthenium dimer
- Los Alamos National Laboratory, NM (United States)
Mixed-valent transition-metal dimers have become key systems for understanding many fundamental aspects of electron-transfer dynamics. The mixed-valent dimer [(NC){sub 5}Ru{sup II}CNRu{sup III}-(NH{sub 3}){sub 5}]{sup 1-} is an interesting member of this class. In this complex, the ruthenium centers are strongly coupled through a short cyanide bridge, but because the [(NC){sub 5}Ru{sub III}CNRu{sub II}(NH{sub 3}){sub 5}]{sub -1} state of this systems lies approximately 8000cm{sup -1} higher in energy, the odd electron is localized on the ruthenium cyanide center. Optical excitation onto the metal-metal charge transfer (MMCT) band leads to reduction of the ruthenium ammine site. This state is highly unstable with respect to back electron transfer. The MMCT excitation is followed by back electron transfer, which may occur on very short time scales, allowing one to observe effects due to ultrafast reorganization processes, to discern excited state/ground state coupling phenomena, and to test modern electron-transfer theories. In this communication, the authors report a picosecond infrared study of the dynamics of [(NC){sub 5}Ru{sup II}CNRu{sup III} (NH{sub 3}){sub 5}]{sup 1-} following MMCT optical excitation. 18 refs., 1 fig., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 236338
- Journal Information:
- Journal of the American Chemical Society, Vol. 114, Issue 8; Other Information: PBD: 8 Apr 1992
- Country of Publication:
- United States
- Language:
- English
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