Recent progress of soft X-ray photoelectron spectroscopy studies of uranium compounds

Fujimori, Shinichi; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Yamamoto, Etsuji; Haga, Yoshinori; Onuki, Yoshichika

Journal of Electron Spectroscopy and Related Phenomena, 208, p.105 - 110, 2016/04

https://doi.org/10.1016/j.elspec.2015.08.001

Recent progresses in the soft X-ray photoelectron spectroscopy (PES) studies ( 100 eV) for uranium compounds are briefly reviewed. The soft X-ray PES has enhanced sensitivities for the bulk U 5f electronic structure, which is essential to understand the unique physical properties of uranium compounds. In particular, the recent remarkable improvement in energy resolutions from an order of 1 eV to 100 meV made it possible to observe fine structures in Uf density of states. Furthermore, soft X-ray ARPES becomes available due to the increase of photon flux at beamlines in third generation synchrotron radiation facilities. The technique made it possible to observe bulk band structures and Fermi surfaces of uranium compounds and therefore, the results can be directly compared with theoretical models such as band-structure calculations. The core-level spectra of uranium compounds show a systematic behavior depending on their electronic structures, suggesting that they can be utilized to determine basic physical parameters such as the U 5f-ligand hybridizations or Coulomb interaction between U 5f electrons. It is shown that soft X-ray PES provides unique opportunities to understand the electronic structures of uranium compounds.

Temperature and polarization dependence of Fe L-edge X-ray absorption spectra of LuFeO

Agui, Akane; Mizumaki, Masaichiro*; Kuroda, Tomoko*; Kawai, Masahiro*; Nagata, Tomoko*; Ikeda, Naoshi*; Uozumi, Takayuki*

Journal of Electron Spectroscopy and Related Phenomena, 197, p.13 - 16, 2014/12

https://doi.org/10.1016/j.elspec.2014.08.008

In this paper, we report on the study of the temperature dependence of Fe L-edge X-ray absorption spectra (XAS) of LuFeO. In the charge ordered state the valence of Fe is in Fe and Fe. And the Fe L-edge XAS spectra have double peak structure which is attributed the Fe and Fe state. In high temperature, the double peak structure becomes indistinct because the thermal excited state overlaps while the Fe valence keeping the integer number.

Local structures and magnetic properties of fullerene-Co systems studied by XAFS and XMCD analyses

Hojo, Ikuko*; Koide, Akihiro*; Matsumoto, Yoshihiro; Maruyama, Takashi*; Nagamatsu, Shinichi*; Entani, Shiro; Sakai, Seiji; Fujikawa, Takashi*

Journal of Electron Spectroscopy and Related Phenomena, 185(1-2), p.32 - 38, 2012/03

https://doi.org/10.1016/j.elspec.2011.11.001

Self-ordering of silicon polymer thin film grown on indium tin oxide surface investigated by X-ray absorption spectroscopy

Mannan, M. A.*; Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Hirao, Norie; Narita, Ayumi; Nagano, Masamitsu*; Noguchi, Hideyuki*

Journal of Electron Spectroscopy and Related Phenomena, 181(2-3), p.242 - 248, 2010/08

https://doi.org/10.1016/j.elspec.2010.02.014

The ordering and molecular orientation of polydimethylsilane (PDMS) films grown on indium tin oxide (ITO) surface has been assigned. The orientation of the samples as well as that of the annealed sample was studied by Si K-edge near-edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy using linearly polarized synchrotron radiation. The Si K-edge NEXAFS spectra for the thick film have at least four resonance peaks of which two peaks are found to be strongly polarization dependent. On the basis of the polarization dependences of the peak intensities, it is revealed that the backbones of the PDMS films are perpendicularly oriented on the ITO surface. The angle between surface and the Si-Si bonds for multilayered film calculated from the helical structure of PDMS molecule was found to be 41.5 which was almost coincided with the experimentally obtained angle of 40 . It was concluded that PDMS molecules are highly self-ordered on ITO surface.

Interatomic Coulombic decay following the Auger decay; Experimental evidence in rare-gas dimers

Ueda, Kiyoshi*; Fukuzawa, Hironobu*; Liu, X.*; Sakai, Katsunori*; Prmper, G.*; Morishita, Yuichiro*; Saito, Norio*; Suzuki, Isao*; Nagaya, Kiyonobu*; Iwayama, Hiroshi*; et al.

Journal of Electron Spectroscopy and Related Phenomena, 166-167, p.3 - 10, 2008/11

https://doi.org/10.1016/j.elspec.2008.03.002

Interatomic Coulombic decay (ICD) in Ar, ArKr and Kr following Ar 2p or Kr 3d Auger decay has been investigated by means of momentum-resolved electron-ion-ion-coincidence spectroscopy. This sequential decay leads to Coulombic dissociation into dication and monocation. Simultaneously determining the kinetic energy of the ICD electron and the kinetic energy release between the two atomic ions, we could unambiguously identify the ICD channels. We find that, in general, spin conserved ICD, in which the singlet (triplet) dicationic state produced via the atomic Auger decay preferentially decays to the singlet (triplet) state, transferring the energy to the other atom, is faster than the spin-flip ICD, in which the Auger final singlet (triplet) dicationic state decays to the triplet (singlet) state.

Photoemission and core-level absorption spectroscopy of FeNbS

Saito, Yuji; Kobayashi, Keisuke*; Fujimori, Atsushi; Yamamura, Yasuhisa*; Koyano, Mikio*; Tsuji, Toshihide*; Katayama, Shinichi*

Journal of Electron Spectroscopy and Related Phenomena, 144-147, p.829 - 832, 2005/06

https://doi.org/10.1016/j.elspec.2005.01.186

no abstracts in English

Characterization and degradation of ZEP520 resist film by TOF-PSID and NEXAFS

Ikeura, Hiromi*; Sekiguchi, Tetsuhiro; Koike, Masaki*

Journal of Electron Spectroscopy and Related Phenomena, 144-147, p.453 - 455, 2005/06

https://doi.org/10.1016/j.elspec.2005.01.152

no abstracts in English

Resonant O K emission spectroscopy of layered manganate LaSrMnO

Agui, Akane; Kmbre, T.*; Sthe, C.*; Nordgren, J.*; Usuda, Manabu; Saito, Tomohiko*; Moritomo, Yutaka*

Journal of Electron Spectroscopy and Related Phenomena, 144-147, p.589 - 592, 2005/06

https://doi.org/10.1016/j.elspec.2005.01.103

Current research in the perovskite and layered perovskite-type manganese oxides has expanded to include the study of electronic and magnetic properties such as the colossal magnetoresistance (CMR), orbital ordering and charge ordering. The O K soft X-ray emission and absorption spectra (XES and XAS) of LaSrMnO were measured at selected excitation energies in order to investigate the electronic structure. The measurements were carried out by using a soft X-ray emission spectrometer at beamline BW3 at HASYLAB, Germany. The dependence of O K XES on excitation-energy was observed. It is attributed the different site of oxygen ions.

Chemical evolution of amino acid induced by soft X-ray with synchrotron radiation

Kaneko, Fusae*; Tanaka, Masahito*; Narita, Satoru*; Kitada, Tomo*; Matsui, Takahiro*; Nakagawa, Kazumichi*; Agui, Akane; Fujii, Kentaro; Yokoya, Akinari

Journal of Electron Spectroscopy and Related Phenomena, 144-147, p.291 - 294, 2005/06

https://doi.org/10.1016/j.elspec.2005.01.233

no abstracts in English

Synchrotron radiation photoabsorption and photoemission spectroscopy for thermal-induced reoriented Si polymer

Nath, K. G.; Shimoyama, Iwao; Sekiguchi, Tetsuhiro; Baba, Yuji

Journal of Electron Spectroscopy and Related Phenomena, 144-147, p.323 - 326, 2005/06

https://doi.org/10.1016/j.elspec.2005.01.185

The effect of laser annealing on electronic atructures and molecular orientation for poly(dimethylsilane), {PDMS, [Si(CH)]} has been studied by synchrotron radiation photoemission and photoabsorption spectroscopy. Prior to annealing, PDMS powder was mounted on the basal plane of highly oriented pyrolytic graphite. Both Si 1s X-ray photoemission spectroscopy and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy at Si 1s edge show that electronic structures have been modified due to annealing. Furthermore, the angle-dependent NEXAFS spectra clearly indicate that the annealed products maintain a specific orientation. Interestingly, no such kind of orientation is present in as-received PDMS powder as no angle-dependency is observed before annealing.