Spin-charge dynamics of iron complex clarified by ultrafast X-ray spectroscopy

The use of X-ray free-electrons has enabled plenty of fascinating science, such as watching non-equilibrium excited-state dynamics in complexes of 3d transition metals. Scientists at LCLS, Stanford have performed femtosecond resolution X-ray fluorescence spectroscopy, with its sensitivity to spin state, elucidating the spin crossover dynamics of [Fe(2, 2ˈ-bipyridine)₃]²⁺ on photoinduced metal-to-ligand charge transfer excitation. For more information, see the paper, "Tracking excited-state charge and spin dynamics in iron coordination complexes", W. Zhang et al., Nature, 509, 345 (2014).