Speaker
Description
We studied the thermo- and photo-induced phase transition between low spin (LS) and high spin (HS) states of the 2x2 grid-like iron complex: Fe4L44·C2H3N (FE4), L=4-methyl-3,5-Bis{6(2,2′-dipyridyl)}pyrazole in solid state, by using X-ray diffraction techniques. The structural analysis of the coordination geometry of the two crystallographically independent metal atoms at different temperatures demonstrates that the formation of the thermo-induced HS in one atom affects the coordination geometry of the other. The analysis of the photo-induced HS over time do not only exhibit similar structural reorganization as the thermo-induced HS state but also a relaxation from HS to LS in less than one nanosecond. The understanding of photo-switching dynamics and its relation with the thermo-induced HS under systems with strong short-range elastic coupling between small set of metal ions, such as the FE4 system, could allow for new mechanism of energy redistribution after photoexcitation and therefore, the design of new storage and processing devices.
