Uranium oxides investigated by X-ray absorption and emission spectroscopies

نویسندگان

  • Martin Magnuson
  • Sergei M. Butorin
  • Lars Werme
  • Joseph Nordgren
  • Kirill E. Ivanov
  • Jinghua Guo
  • David K. Shuh
  • M. Magnuson
  • S. M. Butorin
  • L. Werme
  • D. K. Shuh
چکیده

X-ray absorption and resonant X-ray emission measurements at the O 1s edge of the uranium oxides UO2, U3O8 and UO3 are presented. The spectral shapes of the O Kα X-ray emission spectra of UO3 exhibit significant excitation energy dependence, from an asymmetric to a symmetric form, which differs from those of UO2 and U3O8. This energy dependence is attributed to a significant difference in the oxygen-uranium hybridization between two different sites in the crystal structure of UO3. The spectral shapes of UO2 and U3O8 are also found to be different but without significant energy dependence. The experimental spectra of the valence and conduction bands of the uranium oxides are compared to the results of electronic structure calculations available in the literature.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Chemical Modification of Graphene Oxide by Nitrogenation: An X-ray Absorption and Emission Spectroscopy Study

Nitrogen-doped graphene oxides (GO:Nx) were synthesized by a partial reduction of graphene oxide (GO) using urea [CO(NH2)2]. Their electronic/bonding structures were investigated using X-ray absorption near-edge structure (XANES), valence-band photoemission spectroscopy (VB-PES), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS). During GO:Nx synthesis, different ...

متن کامل

Effect of Annealing Temperature on the Structural, Magnetic and Optical Properties of SrCo2Fe16O27 Hexaferrite Nanostructure

In this paper, W-type SrCo2Fe16O27 hexaferrite nanostructures were synthesized by sol-gel auto-combustion method. Effect of annealing temperature on the structural, magnetic and optical properties of these SrCo2Fe16O27 nanostructures was investigated. In order to determine the annealing temperature of samples, the prepared gel was examined by thermo-gravimetric and differential-thermal analyses...

متن کامل

The electronic structure of poly(pyridine-2,5-diyl) investigated by soft X-ray absorption and emission spectroscopies

The electronic structure of the poly-pyridine conjugated polymer has been investigated by resonant and nonresonant inelastic X-ray scattering and X-ray absorption spectroscopies using synchrotron radiation. The measurements were made for both the carbon and nitrogen contents of the polymer. The analysis of the spectra has been carried out in comparison with molecular orbital calculations taking...

متن کامل

Upper Limits on the X-ray Emission of “Uranium” Stars

A paper by Qian & Wasserburg suggests the optical absorption lines of uranium observed in the spectra of ultra-metal-poor stars (defined as [Fe/H] <-3) arise from contamination from a supernova in a binary star system. Assuming the binary survived the explosion, a collapsed compact object may be present and implying potential accretion processes with accompanying X-ray emission. Upper limits on...

متن کامل

Effect of biogeochemical redox processes on the fate and transport of As and U at an abandoned uranium mine site: an X-ray absorption spectroscopy study

Although As can occur in U ore at concentrations up to 10wt-%, the fate and transport of both U and As at U mine tailings have not been previously investigated at a watershed scale. The major objective of this study was to determine primary chemical and physical processes contributing to transport of both U and As to a down gradient watershed at an abandoned U mine site in South Dakota. Uranium...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2012