Direct observation of light induced spin transitions in new 3,5-bis(2-pyridyl)pyrazolato bridged thiocyanato diiron(II) complexes by monitoring variable temperature laser Raman spectra.

The light induced excited spin state trapping LIESST and the reverse LIESST-like phenomena are observed below and above the spin transition temperature, respectively, for new dinuclear diiron(II) complexes and familiar Fe(II) complexes with thiocyanate ligands by monitoring the Raman spectra where only excitation light of various wavelengths for the spectroscopy was used without extra excitation light sources.