A quantitative analysis is presented for the site-selective Fe K-edge absorption spectra of Prussian Blue: Fe(4)[Fe(CN)(6)](3) x xH(2)O (x = 14-16). The site-selective spectra were recorded using high-resolution fluorescence detection of the K beta emission from a polycrystalline sample. The K beta fluorescence lines arising from the high-spin and low-spin sites are shifted in energy. Since the...

The results of EXAFS measurements at 300 K for the superconducting compounds Tl0.75Cu0.25Ba2Ca3Cu4Oy [Tl-1234], TlBa2Ca3Cu4Oy [Tl-1212], and CuBa2Ca3Cu4Oy [Cu-1234]. are reported. We have measured the EXAFS spectrum for Tl0.75Cu0.25Ba2Ca3Cu4Oy in the range 10K-300K, however here we limit our discussion to the spectrum at 300 K. This material is prepared under high pressure [3.5 GPa] from precur...

The application of high-resolution X-ray spectroscopy methods to study the photosynthetic water oxidizing complex, which contains a unique hetero-nuclear catalytic Mn4Ca cluster, is described. Issues of X-ray damage, especially at the metal sites in the Mn4Ca cluster, are discussed. The structure of the Mn4Ca catalyst at high resolution, which has so far eluded attempts of determination by X-ra...

The terms X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) refer, respectively, to the structure in the X-ray absorption spectrum at low and high energies relative to the absorption edge. Routine analysis of EXAFS experiments generally makes use of simplified models and several many-body parameters, e.g. mean free paths, many-body amplitude facto...

The length scale of the local chemical anisotropy responsible for the growth-temperature-induced perpendicular magnetic anisotropy of face-centered cubic CoPt(3) alloy films was investigated using polarized extended x-ray absorption fine structure (EXAFS). These x-ray measurements were performed on a series of four (111) CoPt(3) films epitaxially grown on (0001) sapphire substrates. The EXAFS d...

X-ray absorption spectroscopy (XAS) refers to the details of how X-rays are absorbed by an atom at energies near and above the core-level binding energies of that particular atom. The absorption of X-rays on the high energy side of absorption edges does not vary monotonically in condensed matter but has a complicated behavior which extends past the edge up to about ~1 keV. This non-monotonic va...

As part of a study of the effect of particle size on reactivity of hematite to aqueous metal ions, the sorption of Zn(II) on hematite nanoparticles and microparticles was examined over a wide range of Zn(II) concentrations using Zn K-edge EXAFS. When reacted with nanoparticles at pH 5.5 and low Zn(II) sorption densities (0.04 < Γ < 2.76 μmol/m), Zn(II) formed five-coordinated or a mixture of fo...

Spin polarized and spin averaged extended x-ray absorption fine structure ((M)EXAFS) data were measured at temperatures of 180 K and 296 K in the soft x-ray energy regime of the overlapping L-edges of an iron film grown on V(110). The absorption coefficients were analyzed with the Bayes-Turchin procedure. The analysis yields the correction function to the atomic-like background-absorption coeff...