Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Ikeura, Hiromi*; Sekiguchi, Tetsuhiro
Japanese Journal of Applied Physics, 58(SI), p.SIIC04_1 - SIIC04_4, 2019/08
Times Cited Count：0 Percentile：0(Physics, Applied)The electronic structure of the unoccupied conduction band of polycrystalline chloroaluminum phthalocyanine was investigated by X-ray absorption spectroscopy (XAS) near the Cl K-edge. XAS spectra were recorded in total electron yield (TEY) and partial Auger electron yield (AEY) modes. Partial AEY spectra were measured using normal and spectator Cl KL
L Auger yields as a function of photon energy. Although the TEY spectrum showed a broad shape; that was difficult to deconvolute curve fitting, the normal and spectator AEY spectra clearly showed that 
*(Cl-Al) transition splits into two competitive peaks attributed to the core excitons (localized with a core hole) and conduction band (delocalized without a core hole). The existence of a band-like peak in the Cl K-edge XAS is evidence that the Cl axial ligand participates in forming the conduction band. Thus, band-like electron transport is expected to occur in the oligomer-like (-Al-Cl-Al-) site.
Ikeura, Hiromi*; Sekiguchi, Tetsuhiro
Molecular Crystals and Liquid Crystals, 622(1), p.50 - 54, 2015/12
Times Cited Count：0 Percentile：0.01(Chemistry, Multidisciplinary)Organic electrically conducting 
-stacked molecules are widely regarded as promising materials for future application of nanoelectronics. Direct measurements of electronic structures of unoccupied states in organic semiconductors lead to better understanding of mechanism of electron conduction. For probing unoccupied partial density of states (DOS), X-ray absorption spectroscopy (XAS) is commonly used, where selective excitation of the 1s core electron to the unoccupied conduction band is possible. However, XAS cannot distinguish localized and delocalized features without comparing any theoretical approach. In this work, the core-hole-clock method in resonant Auger spectroscopy (RAS) has been applied to probe electron delocalization through the empty conduction band in the attosecond domain for the purpose of exploring electronic materials with high-speed electron transport. We will discuss some organic molecules such as pentacenes.
Ogawa, Hiroshi*; Ikeura, Hiromi*; Sekiguchi, Tetsuhiro
Molecular Crystals and Liquid Crystals, 622(1), p.164 - 169, 2015/11
Times Cited Count：0 Percentile：0.01(Chemistry, Multidisciplinary)Unoccupied electronic states near the Fermi level of poly(dimethylsilane) were probed using Si 1s X-ray absorption spectroscopy (XAS) and Si KLL resonant Auger spectroscopy (RAS). The measured resonance peaks of XAS spectra near Si K-edge have been assigned in comparison with the discrete variational (DV)-X
molecular orbital calculations. The rapid delocalization of Si 1s core-excited electron through the empty conduction band was observed along the polymer chain with the energy dependent RAS measurement, and the electron delocalization time was estimated based on the core-hole clock method.
Esaka, Fumitaka
Ekisupato Oyo Kagaku Sirizu; Kiki Bunseki, p.119 - 135, 2015/09
Bulk analysis has been conventionally used for measuring solid materials. In contrast, surface analysis is extensively used for analyzing chemical compositions and chemical states of solid surface. The surface compositions often differ from those of bulk materials. Recently, doping of impurity elements and deposition of thin films on the surface of the materials are key techniques to fabricate functional materials. Therefore, surface analysis becomes important to characterize such materials. In this paper, the principle and feature of some surface analytical techniques are described.
Akamatsu, Ken; Fujii, Kentaro; Yokoya, Akinari
International Journal of Radiation Biology, 80(11-12), p.849 - 853, 2004/11
Times Cited Count：11 Percentile：58.51(Biology)The productions of stable/unstable thymine radicals produced by monochromatic ultrasoft X (USX)- or 
Co 
-rays were studied using EPR spectroscopy. EPR experiment of thymine was performed using a newly developed X-band EPR device installed in a JAERI soft X-ray beamline (BL23SU) in SPring-8. The sample pellet was irradiated with USX photons at a microwave in a vacuum chamber. EPR measurements of a thymine powder pellet irradiated with USX around 500 eV at 77 K and RT. As a reference, Co g-irradiation to the pellet was also performed at RT. As the results, following three findings are obtained: (1) An unstable radical appearing only in situ USX-irradiation is observed. And the radical is clearly distinguished with other stable radicals remaining after irradiation. (2) The signal of the unstable radical is a strong singlet, which vanishes after irradiation immediately.
with HeKawatsura, Kiyoshi*; Takahiro, Katsumi*; Imai, Makoto*; Sataka, Masao; Komaki, Kenichiro*; Shibata, Hiromi*
Nuclear Instruments and Methods in Physics Research B, 205, p.528 - 532, 2003/05
Times Cited Count：4 Percentile：33.69(Instruments & Instrumentation)Auger and Coster-Kronig electron spectra from highly excited states produced by low-energy highly charged ions with gas targets have been investigated both theoretically and experimentally. In this case, the highly excited states were formed by electron capture processes. We have studied collision processes of high-energy highly charged ions with a gas target using zero-degree electron spectroscopy at the tandem accelerator of JAERI, Tokai. In the present, we have measured Auger and C-K electron spectra from highly excited states produced by 1-3 MeV/u O
(q=3-5) + He collisions, where the highly excited states in Oq+ ions were formed by electron excitation. We have compared and discussed the Auger and C-K electron spectra obtained by electron-capture and electron-excitation processes. It is found that the C-K spectra for high-energy Oq+ ions show relatively low-l states and the Auger spectra also have different structures from those for low-energy highly charged Oq+ ions.
Imai, Makoto*; Sataka, Masao; Kitazawa, Shinichi; Komaki, Kenichiro*; Kawatsura, Kiyoshi*; Shibata, Hiromi*; Tawara, Hiroyuki*; Azuma, Toshiyuki*; Kanai, Yasuyuki*; Yamazaki, Y.*
Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.674 - 679, 2002/06
Times Cited Count：5 Percentile：34.58(Instruments & Instrumentation)no abstracts in English
Ioka, Ikuo; Onuki, Kaoru; Futakawa, Masatoshi; Kuriki, Yoshiro*; Nagoshi, Masayasu*; Nakajima, Hayato; Shimizu, Saburo
Ryusan To Kogyo, 52(4), p.1 - 6, 1999/04
no abstracts in English
Sekiguchi, Hiromi*; Sekiguchi, Tetsuhiro
Surface Science, 433-435, p.549 - 553, 1999/00
Times Cited Count：26 Percentile：76.83(Chemistry, Physical)no abstracts in English
Sasaki, Teikichi; Baba, Yuji; Yoshii, Kenji; Yamamoto, Hiroyuki
Hyomen Kagaku, 17(7), p.370 - 374, 1996/07
no abstracts in English
Saito, Yuji; Suga, Shigemasa*; Kakizaki, A.*; Matsushita, T.*; Imada, S.*; Daimon, H.*; Ono, Kanta*; Fujisawa, M.*; Kinoshita, T.*; Ishii, T.*; et al.
Journal of Electron Spectroscopy and Related Phenomena, 78, p.329 - 332, 1996/05
Times Cited Count：0 Percentile：0.03(Spectroscopy)no abstracts in English
Teraoka, Yuden; Baba, Yuji; Sasaki, Teikichi
Photon Factory Activity Report, (14), P. 422, 1996/00
no abstracts in English
and O ion-implanted Si(100)Yamamoto, Hiroyuki; Baba, Yuji; Sasaki, Teikichi
Surface and Interface Analysis, 23, p.381 - 385, 1995/00
Times Cited Count：17 Percentile：53.88(Chemistry, Physical)no abstracts in English
Sasaki, Teikichi
Hyomen, 30(11), p.915 - 927, 1992/00
no abstracts in English
I.Kadar*; H.Altevogt*; R.Koehrbrueck*; V.Montemayor*; A.Mattis*; G.Schiwietz*; B.Skogvall*; K.Sommer*; N.Stolterfoht*; Kawatsura, Kiyoshi*; et al.
Physical Review A, 44(5), p.2900 - 2912, 1991/09
Times Cited Count：5 Percentile：39.05(Optics)no abstracts in English
Kawatsura, Kiyoshi*; Sataka, Masao; Naramoto, Hiroshi; Imai, Makoto; Komaki, Kenichiro*; *; *; Kanai, Yasuyuki*; Kambara, Tadashi*; *; et al.
Nuclear Instruments and Methods in Physics Research B, 53(4), p.421 - 425, 1991/04
Times Cited Count：16 Percentile：83.01(Instruments & Instrumentation)no abstracts in English
, N, CO
, and CO ion bombardmentNagai, Shiro
Nuclear Instruments and Methods in Physics Research B, 59-60, p.936 - 939, 1991/00
Times Cited Count：3 Percentile：50.32(Instruments & Instrumentation)no abstracts in English
Kawatsura, Kiyoshi*; Sataka, Masao; *; Komaki, Kenichiro*; Kanai, Yasuyuki*; Naramoto, Hiroshi; *; Kambara, Tadashi*; *; Nakai, Yota; et al.
Nuclear Instruments and Methods in Physics Research B, 48, p.103 - 106, 1990/00
Times Cited Count：17 Percentile：82.1(Instruments & Instrumentation)no abstracts in English
, CO, O and DONagai, Shiro
Journal of Nuclear Materials, 151, p.275 - 280, 1988/00
no abstracts in English
