Soft X-ray emission spectroscopy at the L-edge of transition metals in metalloproteins
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چکیده
Soft X-ray emission spectroscopy of aqueous myoglobin upon Fe 2p core excitation was carried out using a liquid cell with a 150 nm-thick polyimide window in a high vacuum chamber below 1×10−7 Pa. Fe 2p soft X-ray emission from the heme center of a met-myoglobin powder was effectively detected compared to that of an Fe2O3 powder. Fe 2p soft X-ray emission spectra for a series of aqueous-myoglobin (Mb–CO, Mb–O2, Mb–CN, and met–Mb) indicated significant change in the ligand field and the hybridization energy between Fe 3d and the ligand valence states.
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تاریخ انتشار 2002