Angle-resolved photoemission and first-principles electronic structure of single-crystallineα-U(001)

Abstract

Continuing the photoemission study begun with the work of Opeil et al. [Phys. Rev. B 73, 165109 (2006)], in this paper we report results of an angle-resolved photoemission spectroscopy (ARPES) study performed on a high-quality single-crystal α-uranium at 173 K. The absence of surface-reconstruction effects is verified using X-ray Laue and low-energy electron diffraction (LEED) patterns. We compare the ARPES intensity map with first-principles band structure calculations using a generalized gradient approximation (GGA) and we find good correlations with the calculated dispersion of the electronic bands.

Ab Initio Enhanced calphad Modeling of Actinide-Rich Nuclear Fuels

“…2 of Ref. [68]). Our calculated DOS is however total DOS (TDOS) integrated over the whole Brillouin zone and thus may show additional features not seen in the UPS spectra.…”

“…We make the case on experimentally most-characterized system αU by comparing its calculated valence band electronic structure to experimental photoelectron spectra in Figure 8 and Figure 9. [68] and UPS spectra from Opeil et al [69] for αU(001) single crystal. All experimental spectra are plotted as blue circles, while DFT and DFT+U (U eff =1.24 eV) calculated results are plotted as black and red curves, respectively; solid and dash line style distiguish noSOC and SOC.…”

“…Here, latest experimental ARPES [68] and UPS [69] spectra of αU (001) single crystal are used as references for the calculated band structure (left panel) and density of states (DOS, right panel) of bulk αU, respectively. Before we start the comparison, a few clarifications regarding the experimental spectra should be made.…”

“…Before we start the comparison, a few clarifications regarding the experimental spectra should be made. Firstly, some features of the spectra are due to surface states as the escape depth of the phonon source used is "at most 2-3 atomic layers" [68]. Some of the possible surface states features are suggested based on DFT calculations of bulk αU [68,69].…”

“…Firstly, some features of the spectra are due to surface states as the escape depth of the phonon source used is "at most 2-3 atomic layers" [68]. Some of the possible surface states features are suggested based on DFT calculations of bulk αU [68,69]. These features are marked roughly with gray areas on the left and dash arrows on the right panel of Figure 8.…”