Iron L_2,3-Edge X-ray Absorption and X-ray Magnetic Circular Dichroism Studies of Molecular Iron Complexes with Relevance to the FeMoco and FeVco Active Sites of Nitrogenase.

ABSTRACT: Herein, a systematic study of a series of molecular iron model complexes has been carried out using Fe L_2,3-edge X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopies. This series spans iron complexes of increasing complexity, starting from ferric and ferrous tetrachlorides ([FeCl₄]^-/2-), to ferric and ferrous tetrathiolates ([Fe(SR)₄]^-/2-), to diferric and mixed-valent iron-sulfur complexes [Fe₂S₂R₄]^2-/3-. This test set of compounds is used to evaluate the sensitivity of both Fe L_2,3-edge XAS and XMCD spectroscopy to oxidation state and ligation changes. It is demonstrated that the energy shift and intensity of the L_2,3-edge XAS spectra depe

SUBMITTER: Kowalska JK 

PROVIDER: S-EPMC5516708 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature