Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Time-resolved spectroscopy of photoinduced electron transfer in dinuclear and tetranuclear Fe/Co prussian blue analogues


Schwarzer,  D.
Department of Dynamics at Surfaces, MPI for Biophysical Chemistry, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Zimara, J., Stevens, H., Oswald, R., Demeshko, S., Dechert, S., Mata, R. A., et al. (2021). Time-resolved spectroscopy of photoinduced electron transfer in dinuclear and tetranuclear Fe/Co prussian blue analogues. Inorganic Chemistry, 60(1), 449-459. doi:10.1021/acs.inorgchem.0c03249.

Cite as: https://hdl.handle.net/21.11116/0000-000A-B89E-5
The dynamics of the photodriven charge transfer-
induced spin transition (CTIST) in two Fe/Co Prussian Blue
Analogues (PBAs) are revealed by femtosecond IR and UV/vis
pump−probe spectroscopy. Depending on temperature, the known
tetranuclear square-type complex [Co 2 Fe 2 (CN) 6 (tp*) 2 (4,4′-
dtbbpy) 4](PF 6)2 (1) exists in two electronic states. In acetonitrile
solution, at <240 K, the low temperature (LT) phase is prevalent
consisting of low-spin Fe(II) and low-spin Co(III), [Fe IILS CoIIILS]2 .
Temperature rise is the reason behind thermally-induced CTIST
toward the high temperature (HT) phase consisting of low-spin
Fe(III) and high-spin Co(II), [FeIIILSCoIIHS ]2, being prevalent at
>300 K. Photoexcitation into the intervalence charge transfer
(IVCT) band of the LT phase at 800 nm induces electron transfer in one Fe−Co edge of PBA 1 and produces a [Fe IIILSCoIILS ]
intermediate which by spin-crossover (SCO) is stabilized within 400 fs to a long-lived (>1 ns) [Fe IIILSCo IIHS] species. In contrast,
IVCT excitation of the HT phase at 400 nm generates a [Fe IILSCoIIIHS] species with a lifetime of 3.6 ps. Subsequent back-electron
transfer populates the vibrationally hot ground state, which thermalizes within 8 ps. The newly synthesized dinuclear PBA,
[CoFe(CN)3(tp*)(pz*4Lut)]ClO 4 (2), provides a benchmark of the HT phase of 1, i.e., [Fe IIILSCo IIHS], as verified by variable
temperature magnetic susceptibility measurements and 57 Fe Mö ssbauer spectroscopy. The photoinduced charge transfer dynamics
of PBA 2 indeed are almost identical to that of the HT phase of PBA 1 with a lifetime of the excited [Fe IILSCoIIIHS ] species of 3.8 ps.