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Sugiyama H, Nagano T, Nouchi R, Kawasaki N, Ohta Y, Imai K, Tsutsui M, Kubozono Y, Fujiwara A. Transport properties of field-effect transistors with thin films of C76 and its electronic structure. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.10.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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52
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Mitsuke K, Katayanagi H, Kafle BP, Huang C, Yagi H, Prodhan MSI, Kubozono Y. Relative partial cross sections for single, double, and triple photoionization of C60 and C70. J Phys Chem A 2007; 111:8336-43. [PMID: 17683125 DOI: 10.1021/jp0726034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Partial cross sections for the photoion formation from C(60) and C(70) were determined from the yields of singly, doubly, and triply charged ions which were measured by mass spectrometry combined with tunable synchrotron radiation at hnu = 25-120 eV. The dependence of the detection efficiencies on the mass-to-charge ratio was evaluated by using the formula proposed by Twerenbold et al. Corrections of the detection efficiency were found to be critical for obtaining accurate partial cross sections for photoionization of fullerenes. Revisions were made of the partial cross-section curves for single and double photoionization of C(60) and C(70). The curve for triple photoionization of C(70) was newly proposed. The ratios between the cross sections for double and single photoionization increase with hnu and reach saturated values of 0.78 at 85 eV for C(60) and approximately 1.3 at 100 eV for C(70). In contrast, the ratios at 120 eV between the cross sections for triple and single photoionization of C(60) and C(70) amount to 0.14 and approximately 0.38, respectively. The formation mechanism of multiply charged fullerene ions was discussed in terms of valence-electron excitation to antibonding unoccupied orbitals and/or spherical standing waves inside the cavity of a fullerene. This excitation could be followed by Spectator Auger processes and transmission of the excess electronic energy among numerous vibrational degrees of freedom.
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Nouchi R, Masunari K, Ohta T, Kubozono Y, Iwasa Y. Ring of C60 polymers formed by electron or hole injection from a scanning tunneling microscope tip. PHYSICAL REVIEW LETTERS 2006; 97:196101. [PMID: 17155645 DOI: 10.1103/physrevlett.97.196101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 05/31/2006] [Indexed: 05/12/2023]
Abstract
Carrier (electron or hole) injection from a scanning tunneling microscope tip causes various surface modifications on the molecular scale. We report that injection into C60 close-packed layers forms a ring-shaped distribution of C60 polymers. This can be explained on the basis of the radial propagation and energy dissipation of carriers. Subsequent electron or hole injections enlarge the ring, showing that both carriers can induce both polymerization and depolymerization. Furthermore, we demonstrate visualization of carrier scattering by injecting carriers into C60 layers with grain boundaries.
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Kou J, Mori T, Kumar SVK, Haruyama Y, Kubozono Y, Mitsuke K. Double photoionization of C(60) and C(70) in the valence region. J Chem Phys 2006; 120:6005-9. [PMID: 15267482 DOI: 10.1063/1.1651478] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Photoion yields from gaseous fullerenes, C(60) and C(70), for production of singly and doubly charged ions are measured by mass spectrometry combined with tunable synchrotron radiation at hnu=25-150 eV. Since the signal of triply or highly charged ions is very weak, the total photoionization yield curve can be estimated from the sum of the yields of the singly and doubly charged ions. A distinct feature appears in the resultant curve of C(60) which is absent in the calculated total photoabsorption cross section previously reported. This difference is attributed to C(60) (2+) ions chiefly produced by spectator Auger ionization of the shape resonance states followed by tunneling of the trapped electron or by cascade Auger ionization. Ratios between the yields of doubly and singly charged ions for C(60) and C(70) are larger than unity at hnu>50 eV. These ratios are quite different from those reported in the experiments using electron impact ionization.
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Fujiki S, Masunari K, Nouchi R, Sugiyama H, Kubozono Y, Fujiwara A. Nanoscale patterning by manipulation of single C60 molecules with a scanning tunneling microscope. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2005.12.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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56
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Mitsuke K, Mori T, Kou J, Haruyama Y, Kubozono Y. 4d→4f dipole resonance of the metal atom encapsulated in a fullerene cage: Ce@C82. J Chem Phys 2005; 122:064304. [PMID: 15740369 DOI: 10.1063/1.1846674] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The yield curves for photoions from Ce@C(82) are measured by using synchrotron radiation in the photon energy range from 90 to 160 eV. Parent Ce@C(82) (z+) and fragment ions C(60) (z+) and C(70) (z+) are observed in a mass spectrum (z=1 and 2). The yield curves for doubly charged ionic species exhibit broad resonance in the photon energy region of from 120 to 140 eV which is ascribed to the 4d-->4f giant dipole resonance of the encapsulated Ce atom. The total photoabsorption cross section of Ce@C(82) was determined from partial photoionization cross sections for formation of the parent and fragment ions to be 5.3(-1.1) (+1.8) and 19.6(-3.9) (+6.5) Mb at photon energies of 110 and 130 eV, respectively.
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Kou J, Mori T, Kubozono Y, Mitsuke K. Photofragmentation of C60in the extreme ultraviolet: statistical analysis on the appearance energies of C60−2nz+(n ≥ 1, z = 1–3). Phys Chem Chem Phys 2005. [DOI: 10.1039/b416503a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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58
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Rikiishi Y, Kubozono Y, Hosokawa T, Shibata K, Haruyama Y, Takabayashi Y, Fujiwara A, Kobayashi S, Mori S, Iwasa Y. Structural and Electronic Characterizations of Two Isomers of Ce@C82. J Phys Chem B 2004. [DOI: 10.1021/jp049787w] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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59
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Takabayashi Y, Haruyama Y, Rikiishi Y, Hosokawa T, Shibata K, Kubozono Y. Preferred location of the Dy ion in the minor isomer of Dy@C82 determined by Dy LIII-edge EXAFS. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.02.065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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60
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Kanbara T, Shibata K, Fujiki S, Kubozono Y, Kashino S, Urisu T, Sakai M, Fujiwara A, Kumashiro R, Tanigaki K. N-channel field effect transistors with fullerene thin films and their application to a logic gate circuit. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.07.025] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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61
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Kou J, Mori T, Ono M, Haruyama Y, Kubozono Y, Mitsuke K. Molecular- and atomic-like photoionization of C60 in the extreme ultraviolet. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)00613-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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62
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Takenobu T, Chi DH, Margadonna S, Prassides K, Kubozono Y, Fitch AN, Kato KI, Iwasa Y. Synthesis, structure, and magnetic properties of the fullerene-based ferromagnets Eu3C70 and Eu9C70. J Am Chem Soc 2003; 125:1897-904. [PMID: 12580617 DOI: 10.1021/ja0288690] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Intercalation of C(70) with europium affords two kinds of magnetic compounds, a canted antiferromagnet Eu(x)C(70) (x approximately 3) and a ferromagnet Eu(x)C(70) (x approximately 9) with transition temperatures (T(C)) of 5 and 38 K, respectively. The Curie constants in the paramagnetic phase and the saturation moment in the ferromagnetic phase are both understood by the full moment of Eu(2+) for both systems. The structure of Eu(3)(-)(delta)C(70) (delta approximately 0.27) is pseudo-monoclinic, derived by a simple deformation of the parent face-centered cubic (fcc) structure. Eu(9)(-)(delta)C(70) (delta approximately 0.2) forms an fcc structure, in which cuboctahedral clustering of Eu(2+) ions is observed in the enhanced size octahedral holes. The observed T(C) of the Eu(9)(-)(delta)C(70) ferromagnet is comparable to or larger than those of simple binary Eu-based ferromagnets, such as Eu chalcogenides or carbides, despite the low atomic ratio of Eu in the chemical formulas. This can be understood by the short Eu(2+)-Eu(2+) distances and high coordination numbers permitted by the multiple occupation by Eu(2+) ions of the expanded octahedral interstitial sites in higher fullerene-based solids.
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Neretin IS, Slovokhotov YL, Kubozono Y, Kashino S. Rotational disorder of fullerenes: analysis of structural data. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302097854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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64
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Hieu Chi D, Iwasa Y, Chen X, Takenobu T, Ito T, Mitani T, Nishibori E, Takata M, Sakata M, Kubozono Y. Bridging fullerenes with metals. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00297-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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65
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Ishida H, Nakai T, Kumagae N, Kubozono Y, Kashino S. Crystal structure and phase transition in tert -butylammonium tetrafluoroborate studied by single crystal X-ray diffraction. J Mol Struct 2002. [DOI: 10.1016/s0022-2860(01)00899-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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66
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Iida S, Kubozono Y, Slovokhotov Y, Takabayashi Y, Kanbara T, Fukunaga T, Fujiki S, Emura S, Kashino S. Structure and electronic properties of Dy@C82 studied by UV–VIS absorption, X-ray powder diffraction and XAFS. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00234-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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67
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Fujiki S, Kubozono Y, Takabayashi Y, Kashino S, Emura S. XAFS study on a pressure-induced superconductor Cs3C60 under high pressure. JOURNAL OF SYNCHROTRON RADIATION 2001; 8:725-727. [PMID: 11512910 DOI: 10.1107/s0909049501000218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2000] [Accepted: 01/02/2001] [Indexed: 05/23/2023]
Abstract
Cs K-edge XAFS of Cs3C60 which is a pressure-induced superconductor were measured at 21 and 34 kbar by using a diamond anvil cell (DAC) in order to obtain the structural information under high pressure, and to clarify the origin of the pressure-induced superconductivity. The distances and the mean square displacements between the Cs and C atoms are consistent with those determined by X-ray powder diffraction. Consequently, the high-pressure XAFS can give the reliable structural-information on a fullerene superconductor under high pressure. We also show the procedure of the analysis of high-pressure XAFS with DAC in detail.
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Kubozono Y, Inoue T, Takabayashi Y, Fujiki S, Kashino S, Akasaka T, Wakahara T, Inakuma M, Kato H, Sugai T, Shinohara H, Emura S. XAFS study on metal endohedral fullerenes. JOURNAL OF SYNCHROTRON RADIATION 2001; 8:551-553. [PMID: 11512848 DOI: 10.1107/s0909049500017155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2000] [Accepted: 11/10/2000] [Indexed: 05/23/2023]
Abstract
Structure of metal endohedral fullerenes is studied by XAFS and XANES. The Sc-Sc distance of 2.23(1) A determined from Sc K-edge XAFS supports the formation of a triangular Sc3 cluster in Sc3@C82 as is found by MEM analysis for the X-ray diffraction. Gd L(III)-edge XAFS of Gd@C82 shows that the first and the second neigboring Gd-C distances are 2.51(2) and 2.85(4) A, respectively. The La-La distance of La2@C80 has been determined to be 3.90(1) A at 40 K. This value does not change when increasing temperature [3.90(2) A at 240 K]. The position and the valenece of the Eu atom in Eu@C60 are also discussed based on Eu L(III)-edge XAFS and XANES.
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69
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Kubozono Y, Takabayashi Y, Kashino S, Kondo M, Wakahara T, Akasaka T, Kobayashi K, Nagase S, Emura S, Yamamoto K. Structure of La2@C80 studied by La K-edge XAFS. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00048-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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70
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Inoue T, Kubozono Y, Kashino S, Takabayashi Y, Fujitaka K, Hida M, Inoue M, Kanbara T, Emura S, Uruga T. Electronic structure of Eu@C60 studied by XANES and UV–VIS absorption spectra. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(99)01309-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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71
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Takahashi M, Harada M, Watanabe I, Uruga T, Tanida H, Yoneda Y, Emura S, Tanaka T, Kimura H, Kubozono Y, Kikkawa S. Eu K-XAFS of europium dioxymono-cyanamide with the conversion He+ ion yield method. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:222-224. [PMID: 15263256 DOI: 10.1107/s0909049599001491] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 01/26/1999] [Indexed: 05/24/2023]
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72
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Uruga T, Tanida H, Yoneda Y, Takeshita K, Emura S, Takahashi M, Harada M, Nishihata Y, Kubozono Y, Tanaka T, Yamamoto T, Maeda H, Kamishima O, Takabayashi Y, Nakata Y, Kimura H, Goto S, Ishikawa T. The XAFS beamline BL01B1 at SPring-8. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:143-145. [PMID: 15263227 DOI: 10.1107/s0909049598016173] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 11/30/1998] [Indexed: 05/24/2023]
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73
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Kubozono Y, Mimura K, Takabayashi Y, Maeda H, Kashino S, Emura S, Nishihata Y, Uruga T, Tanaka T, Takahashi M. XAFS study on RbC60. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:564-566. [PMID: 15263381 DOI: 10.1107/s0909049598016021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 11/26/1998] [Indexed: 05/24/2023]
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74
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Nishihata Y, Emura S, Maeda H, Kubozono Y, Harada M, Uruga T, Tanida H, Yoneda Y, Mizuki J, Emoto T. XAFS spectra in the high-energy region measured at SPring-8. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:149-151. [PMID: 15263229 DOI: 10.1107/s0909049598016781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 12/07/1998] [Indexed: 05/24/2023]
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75
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Inoue T, Kubozono Y, Hiraoka K, Mimura K, Maeda H, Kashino S, Emura S, Uruga T, Nakata Y. XAFS study on Eu@C60. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:779-780. [PMID: 15263456 DOI: 10.1107/s0909049598016288] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 12/01/1998] [Indexed: 05/24/2023]
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