1. Identification of the dominant photochemical pathways and mechanistic insights to the ultrafast ligand exchange of Fe(CO)5 to Fe(CO)4EtOH
- Author
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Kunnus, K., Josefsson, I., Rajkovic, I., Schreck, S., Quevedo, W., Beye, M., Weniger, C., Grübel, S., Scholz, M., Nordlund, D., Zhang, W., Hartsock, R. W., Gaffney, K. J., Schlotter, W. F., Turner, J. J., Kennedy, B., Hennies, F., De Groot, F. M F, Techert, S., Odelius, M., Wernet, Ph, Föhlisch, A., Sub Inorganic Chemistry and Catalysis, Inorganic Chemistry and Catalysis, Sub Inorganic Chemistry and Catalysis, and Inorganic Chemistry and Catalysis
- Subjects
ultrafast ligand exchange ,Fe(CO)5 ,Fe(CO)4EtOH ,Metal carbonyl ,Invited Articles ,02 engineering and technology ,Electronic structure ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Molecular dynamics ,Ab initio quantum chemistry methods ,Spin crossover ,lcsh:QD901-999 ,ddc:530 ,Instrumentation ,Institut für Biochemie und Biologie ,Spectroscopy ,Radiation ,Chemistry ,SPECIAL TOPIC: THE HAMBURG CONFERENCE ON FEMTOCHEMISTRY (FEMTO12) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Photoexcitation ,13. Climate action ,Excited state ,Inhouse research on structure dynamics and function of matter ,lcsh:Crystallography ,0210 nano-technology ,Ground state - Abstract
We utilized femtosecond time-resolved resonant inelastic X-ray scattering and ab initio theory to study the transient electronic structure and the photoinduced molecular dynamics of a model metal carbonyl photocatalyst Fe(CO)(5) in ethanol solution. We propose mechanistic explanation for the parallel ultrafast intra-molecular spin crossover and ligation of the Fe(CO)(4) which are observed following a charge transfer photoexcitation of Fe(CO)(5) as reported in our previous study [ Wernet et al., Nature 520, 78 (2015)]. We find that branching of the reaction pathway likely happens in the (1)A(1) state of Fe(CO)(4). A sub-picosecond time constant of the spin crossover from B-1(2) to B-3(2) is rationalized by the proposed B-1(2) -> (1)A(1) -> B-3(2) mechanism. Ultrafast ligation of the B-1(2) Fe(CO)(4) state is significantly faster than the spin-forbidden and diffusion limited ligation process occurring from the B-3(2) Fe(CO)(4) ground state that has been observed in the previous studies. We propose that the ultrafast ligation occurs via B-1(2) -> (1)A(1) -> (1)A'Fe(CO)(4)EtOH pathway and the time scale of the (1)A(1) Fe(CO)(4) state ligation is governed by the solute-solvent collision frequency. Our study emphasizes the importance of understanding the interaction of molecular excited states with the surrounding environment to explain the relaxation pathways of photoexcited metal carbonyls in solution. (C) 2016 Author(s).
- Published
- 2016
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