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Register a new userUltrafast intersystem crossing in nickel porphyrins
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Added by
Javier Fernandez-Rodriguez
Publication date
2015
fields
Physics
and research's language is
English
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We study the relaxation dynamics and intersystem-crossing to the metastable state in laser-pumped tetra and hexa-coordinated nickel porphyrins. We use a ligand-field model which takes into account the crystal field created by the porphyrin ring and axial ligands. By accounting for the energy redistribution of the lattice vibrations of the metal-ligand stretch mode we get an irreversible decay within the order of the hundreds of femtoseconds timescale. We show how non-equilibrium time-dependent x-ray absorption atthe Ni K-edge measurements can elucidate the nature of the intermediate states involved in the decay. Understanding radiationless transitions in this system is of interest for their relevance in photocatalytic systems and photothermal sensitizers for cancer treatment.
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