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Ultrafast intersystem crossings in Fe-Co Prussian blue analogues
1Department of Physics, Northern Illinois University, DeKalb, Illinois, 60115, USA. veenendaal@niu.edu.
Abstract:
Ultrafast spincrossover is studied in Fe-Co Prussian blue analogues using a dissipative quantum-mechanical model of a cobalt ion coupled to a breathing mode. All electronic interactions are treated on an equal footing. It is theoretically demonstrated that the divalent cobalt ion reaches 90% of the [Formula: see text] value within 20 fs after photoexciting a low-spin Co3+ ion by an iron-to-cobalt charge transfer. The doublet-to-quartet spin crossover is significantly faster than the oscillation period of the breathing mode. The system relaxes to the lowest manifold of divalent cobalt (4 T 1) in 150-200 fs. Strong oscillations in spin-orbit coupling and the involvement of higher-lying quartets are found.
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