Light-induced formation of metastable high-spin states in [Fe(mtz)6](CiO4)2

[Fe(mtz)6](CiO4)2 (mtz=1-methyltetrazole) is a spin crossover compound with two different iron(II) lattice sites. Only one of them (lattice site A) shows thermally induced high spin (HS) ⇌ low spin (LS) spin transition. The LIESST effect (Light-Induced Excited Spin State Trapping) can be observed below 50 K. Complex molecules in B-sites remain in HS state at all temperatures. At ∼ 20 K irradiation with red light causes a partial conversion to another HS species, HS(C), with also practically infinite lifetime.

Poster contributions