Azotobacter vinelandii nitrogenase Fe protein (Av2) provides a rare opportunity to investigate a [4Fe-4S] cluster at three oxidation levels in the same protein environment. Here, we report the structural and vibrational changes of this cluster upon reduction using a combination of NRVS and EXAFS spectroscopies and DFT calculations. Key to this work is the synergy between these three techniques...

NifB-co, an Fe-S cluster produced by the enzyme NifB, is an intermediate on the biosynthetic pathway to the iron molybdenum cofactor (FeMo-co) of nitrogenase. We have used Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy together with (57)Fe nuclear resonance vibrational spectroscopy (NRVS) to probe the structure of NifB-co while bound to the NifX protein from Azotobacter...

Details of the surface structure bimetallic catalysts, essential in heterogeneous and electro-catalysis, obtained by analysis EXAFS data under different atmospheres.

Complexation of [UO2](2+) with Cl(-), Br(-), and I(-) in N,N-dimethylformamide (DMF) was studied by UV-vis absorption spectroscopy and extended X-ray absorption fine structure (EXAFS) to clearly differentiate halide coordination strengths to [UO2](2+). In the Cl(-) system, it was clarified that the Cl(-) coordination to [UO2](2+) in DMF proceeds almost quantitatively. The coordination number of...

The temperature and wavenumber dependence of the extended X-ray absorption fine-structure (EXAFS) oscillation hexagonal close-packed (h.c.p.) crystals have been calculated analyzed under effect non-ideal axial ratio c / a . anharmonic EXAFS is presented in terms Debye–Waller factor using cumulant expansion approach up to fourth order. An effective calculation model expanded developed from many-...

Vibrational and elastic properties of the $R$Fe$_{4}$Sb$_{12}$ skutterudites are investigated by, respectively, temperature $(T)$ dependent extended X-ray absorption fine structure (EXAFS) pressure $(P)$ x-ray diffraction (XRD) experiments. The Fe $K$-edge EXAFS experiments $R=$ K, Ca Ba materials were performed in $T$-interval $6<T<300$ K XRD Na, Ca, Sr $P$-interval $1\text{ atm }<P<16$ GPa. F...

The aqua ions of palladium(II) and platinum(II) undergo extremely slow hydrolysis in strongly acidic aqueous solution, resulting in polynuclear complexes. The size and structures of these species have been determined by EXAFS and small angle X-ray scattering, SAXS. For palladium(II), the EXAFS data show that the Pd-O and Pd···Pd distances are identical to those of crystalline palladium(II) oxid...