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Initial Processes of Proton Transfer in Salicylideneaniline Studied by Time-Resolved Photoelectron Spectroscopy  [cached]
Sekikawa Taro,Schalk Oliver,Wu Guorong,Boguslavskiy Andrey E.
EPJ Web of Conferences , 2013, DOI: 10.1051/epjconf/20134102031
Abstract: Excited state intramolecular proton transfer (ESIPT) in salicylideneaniline (SA) and selected derivatives substituted in para-position of the anilino group has been investigated by femtosecond time-resolved photoelectron spectroscopy (TRPES) and time-dependent density functional theory (TDDFT). The planarity of the molecule was found to be a key parameter to describe ESIPT.
Electronic structures of ferromagnetic superconductors $\mathrm{UGe}_2$ and $\mathrm{UCoGe}$ studied by angle-resolved photoelectron spectroscopy  [PDF]
Shin-ichi Fujimori,Takuo Ohkochi,Ikuto Kawasaki,Akira Yasui,Yukiharu Takeda,Tetsuo Okane,Yuji Saitoh,Atsushi Fujimori,Hiroshi Yamagami,Yoshinori Haga,Etsuji Yamamoto,Yoshichika Onuki
Physics , 2015, DOI: 10.1103/PhysRevB.91.174503
Abstract: The electronic structures of the ferromagnetic superconductors $\mathrm{UGe}_2$ and $\mathrm{UCoGe}$ in the paramagnetic phase were studied by angle-resolved photoelectron spectroscopy using soft X-rays ($h\nu =400-500$). The quasi-particle bands with large contributions from $\mathrm{U}~5f$ states were observed in the vicinity of $E_\mathrm{F}$, suggesting that the $\mathrm{U}~5f$ electrons of these compounds have an itinerant character. Their overall band structures were explained by the band-structure calculations treating all the $\mathrm{U}~5f$ electrons as being itinerant. Meanwhile, the states in the vicinity of $E_\mathrm{F}$ show considerable deviations from the results of band-structure calculations, suggesting that the shapes of Fermi surface of these compounds are qualitatively different from the calculations, possibly caused by electron correlation effect in the complicated band structures of the low-symmetry crystals. Strong hybridization between $\mathrm{U}~5f$ and $\mathrm{Co}~3d$ states in $\mathrm{UCoGe}$ were found by the $\mathrm{Co}~2p-3d$ resonant photoemission experiment, suggesting that $\mathrm{Co}~3d$ states have finite contributions to the magnetic, transport, and superconducting properties.
Doping-dependence of nodal quasiparticle properties in high-$T_{\rm c}$ cuprates studied by laser-excited angle-resolved photoemission spectroscopy  [PDF]
K. Ishizaka,T. Kiss,S. Izumi,M. Okawa,T. Shimojima,A. Chainani,T. Togashi,S. Watanabe,C. -T. Chen,X. Y. Wang,T. Mochiku,T. Nakane,K. Hirata,S. Shin
Physics , 2007, DOI: 10.1103/PhysRevB.77.064522
Abstract: We investigate the doping dependent low energy, low temperature ($T$ = 5 K) properties of nodal quasiparticles in the d-wave superconductor Bi$_{2.1}$Sr$_{1.9}$CaCu$_2$O$_{8+\delta}$ (Bi2212). By utilizing ultrahigh resolution laser-excited angle-resolved photoemission spectroscopy, we obtain precise band dispersions near $E_{F}$, mean free paths and scattering rates ($\Gamma$) of quasiparticles. For optimally and overdoped, we obtain very sharp quasiparticle peaks of 8 meV and 6 meV full-width at half-maximum, respectively, in accord with terahertz conductivity. For all doping levels, we find the energy-dependence of $\Gamma \sim |\omega |$, while $\Gamma$($\omega =0$) shows a monotonic increase from overdoping to underdoping. The doping dependence suggests the role of electronic inhomogeneity on the nodal quasiparticle scattering at low temperature (5 K $\lsim 0.07T_{\rm c}$), pronounced in the underdoped region.
Ab-initio angle and energy resolved photoelectron spectroscopy with time-dependent density-functional theory  [PDF]
U. De Giovannini,D. Varsano,M. A. L. Marques,H. Appel,E. K. U. Gross,A. Rubio
Physics , 2012, DOI: 10.1103/PhysRevA.85.062515
Abstract: We present a time-dependent density-functional method able to describe the photoelectron spectrum of atoms and molecules when excited by laser pulses. This computationally feasible scheme is based on a geometrical partitioning that efficiently gives access to photoelectron spectroscopy in time-dependent density-functional calculations. By using a geometrical approach, we provide a simple description of momentum-resolved photoe- mission including multi-photon effects. The approach is validated by comparison with results in the literature and exact calculations. Furthermore, we present numerical photoelectron angular distributions for randomly oriented nitrogen molecules in a short near infrared intense laser pulse and helium-(I) angular spectra for aligned carbon monoxide and benzene.
Excited state dynamics of liquid water near the surface  [cached]
Buchner Franziska,Ritze Hans-Hermann,Beutler Marcus,Schultz Thomas
EPJ Web of Conferences , 2013, DOI: 10.1051/epjconf/20134106006
Abstract: Time resolved photoelectron spectroscopy explores the excited state dynamics of liquid water in presence of cations close to the surface. A transient hydrated electroncation complex is observed.
Theoretical Investigation of Femtosecond-Resolved Photoelectron Spectrum of NaI Molecules

LIU Yu-Fang,ZHAI Hong-Sheng,GAO Ya-Li,LIU Rui-Qiong,

中国物理快报 , 2008,
Abstract: The time-resolved photoelectron spectra (TRPES) of NaI molecules are calculated by using the time-dependent wave packet method. Two different potential energy curves (adiabatic and diabatic) are adopted in the simulation. The third peak of the photoelectron spectra presented in the adiabatic calculation is induced by the reflection of the wave packet. The oscillating of the wave packet onto the diabatic energy curve is a decreasing process. The comparison of the photoelectron spectra between the two different calculations (adiabatic and diabatic) is presented.
Coherent wave packet dynamics in photo-excited Nal  [cached]
Leitner T.,Buchner F.,Luebcke A.,Rouzée A.
EPJ Web of Conferences , 2013, DOI: 10.1051/epjconf/20134102027
Abstract: Time and energy resolved photoelectron distributions of photo-excited Nal are presented. A splitting in the photo-excited state suggested by calculations of the intramolecular potential energy surfaces could be confirmed experimentally for the first time.
Nonstoichiometry in Studied by Ion Beam Methods and Photoelectron Spectroscopy
K. Zakrzewska
Advances in Materials Science and Engineering , 2012, DOI: 10.1155/2012/826873
Abstract: This paper treats a problem of nonstoichiometry in TiO2? thin films deposited by reactive sputtering at controlled sputtering rates. Ion beam techniques, Rutherford backscattering (RBS), and nuclear reaction analysis (NRA) along with X-ray photoelectron spectroscopy have been applied to determine a deviation from stoichiometry in the bulk and at the surface of TiO2? layers. The critical review of these experimental methods is given. Defect structure responsible for the electrical resistivity of rutile TiO2 is discussed.
Growth and spin-resolved photoelectron spectroscopy of the MgO/Fe(110) system  [PDF]
Yu. S. Dedkov,M. Fonin,U. Rüdiger,G. Güntherodt
Physics , 2004,
Abstract: Electronic and structural properties of ultrathin MgO layers grown on epitaxial Fe(110) films were investigated at room temperature by means of spin-resolved photoelectron spectroscopy, Auger-electron spectroscopy, and low energy electron diffraction. The spin polarization at the Fermi level of the Fe(110) film decreases abruptly with increasing thickness of MgO layer up to 7 \AA. This behavior is attributed to the formation of a thin FeO layer at the MgO(111)/Fe(110) interface, attenuating the intrinsic spin polarization.
Many-body theory for angular resolved photoelectron spectra of metal clusters  [PDF]
Andrey V. Solov'yov,Roman G. Polozkov,Vadim K. Ivanov
Physics , 2009,
Abstract: Angular resolved photoelectron spectra of metal clusters have been experimentally measured for the first time only recently. These measurements have been performed systematically for sodium clusters in a broad range of cluster sizes. This work attracted a lot of attention and was reported practically at all major international cluster conferences because it revealed a very non-trivial behavior of the angular anisotropy parameter with respect to photon energy and provided a method for probing the angular momentum character of the valence orbitals of free nanoclusters. Initial attempts to explain these observations within single particle approximations fail completely. In this Letter we present a consistent many-body theory for the description of angular resolved photoelectron spectra of metal clusters. Jellium model formalism is employed. Our calculations demonstrate the dominant role of the many-body effects in the formation of angular distributions of photoelectrons emitted from sodium clusters and are in a good agreement with experimental data reported in. The concrete comparison of theory and experiment has been performed for the photoionization of $Na_7^{-}$ and $Na_{19}^{-}$ anions being characterized by the entirely closed shells of delocalized electrons.
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