K-edge x-ray-absorption spectrum of potassium

Temperature dependence of the pre-edge structure in the Ti K-edge x-ray absorption spectrum of rutile.

The temperature dependence of the pre-edge features in x-ray absorption spectroscopy is reviewed. Then, the temperature dependence of the pre-edge structure at the K-edge of titanium in rutile TiO(2) is measured at low and room temperature. The first two peaks grow with temperature. The fact that these two peaks also correspond to electric quadrupole transitions is explained by a recently propo...

Polarized X-ray Absorption near Edge Structure

Polarized measurements of oriented single crystals can be used to simplify the interpretation of X-ray absorption near edge structure (XANES) spectra by permitting a direct determination of the symmetry properties of a particular transition. We have utilized this technique to study the XANES spectra for several first-row transition metal complexes. Applications to the weak, ls+3d transition, to...

Discovery of a transient absorption edge in the X-ray spectrum of GRB 990705.

We report the discovery of a transient equivalent hydrogen column density with an absorption edge at approximately 3.8 kiloelectron volts in the spectrum of the prompt x-ray emission of gamma-ray burst (GRB) 990705. This feature can be satisfactorily modeled with a photoelectric absorption by a medium located at a redshift of approximately 0.86 and with an iron abundance of approximately 75 tim...

Chemical Effects on K-x-ray Spectrum

Characterization of calcium carbonate polymorphs with Ca K edge X-ray absorption fine structure spectroscopy.

Ca K edge X-ray absorption fine structure (XAFS) spectroscopy was utilized for the characterization and quantification of calcium carbonate polymorphs and their mixtures. The advantage of the XAFS is the small sample quantity required for measurements, and a flexible sample environment. The near-edge XAFS spectra of calcite, aragonite and vaterite were measured with the conversion electron yiel...