| 1. |
- Kurmaev, E. Z., et al.
(författare)
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Spectroscopic observation of polaron-lattice band structure in the conducting polymer polyaniline
- 2001
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 13:17, s. 3907-3912
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Tidskriftsartikel (refereegranskat)abstract
- We present the results of soft x-ray emission measurements for undoped and protonated polyemeraldine. We show that the polaron-lattice band structure fully accounts for the observed x-ray transitions. A finite spectral intensity of C Kα and N Kα XES is observed at the Fermi level for protonated polyemeraldine, supporting the applicability of the polaronic-metal model for highly conducting polymers.
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| 2. |
- Butorin, SM, et al.
(författare)
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Low-energy d-d excitations in MnO studied by resonant x-ray fluorescence spectroscopy
- 1996
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - 0163-1829. ; 54:7, s. 4405-4408
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We measured the Mn L(alpha,beta) x-ray fluorescence spectra of MnO excited by selected photon energies near the L(2,3) absorption edges. The resulting resonant inelastic x-ray scattering spectra probe low-lying electronic excited states, due to dd and cha
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| 3. |
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| 4. |
- Butorin, S. M., et al.
(författare)
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Low-Energy d-d Excitations in MnO Studied by Resonant X-ray Fluorescence Spectroscopy
- 1997
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Ingår i: Advanced Light Source. - Berkely : Ernest Orlando Lawrence Berkeley National Laboratory University of California Berkeley, California. ; , s. 135-136
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Resonant soft X-ray emission spectroscopy has been demonstrated to possess interesting abilities for studies of electronic structure in various systems, such as symmetry probing, alignment and polarization dependence, sensitivity to channel interference, etc. (see other abstracts in this Annual Report). In the present abstract we focus on the feasibility of resonant soft X-ray emission to probe low energy excitations by means ofresonant electronic X-ray Raman scattenng....
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| 5. |
- Butorin, S. M., et al.
(författare)
-
Low-energy d-d excitations in MnO studied by resonant x-ray fluorescence spectroscopy
- 1996
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 54, s. 4405-4408
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Tidskriftsartikel (refereegranskat)abstract
- We measured the Mn Lα,β x-ray fluorescence spectra of MnO excited by selected photon energies near the L2,3 absorption edges. The resulting resonant inelastic x-ray scattering spectra probe low-lying electronic excited states, due to dd and charge-transfer excitations. Using a two-step model and a purely atomic approximation, we reproduce both energies and varying intensities of dd excitations relative to the electronic recombination peak. Our results show that strongly varying line shapes in resonant x-ray emission need not be due to channel interference effects.
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| 6. |
- Butorin, S. M., et al.
(författare)
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Resonant inelastic soft X-ray scattering at the 4d edge of Ce-based heavy fermion materials
- 1999
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Ingår i: Journal of Electron Spectroscopy and Related Phenomena. - 0368-2048 .- 1873-2526. ; 101-103, s. 783-786
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Tidskriftsartikel (refereegranskat)abstract
- Resonant X-ray scattering measurements were performed on CeB6, CeAl, γ-Ce, and α-Ce at various incident-photon energies near the Ce 4d threshold. A pronounced inelastic scattering structure which has 4f character is observed at about 4 eV below the elastic peak. The structure shows a distinct resonant behavior as well as a dependence on the degree of 4f hybridization and can therefore be attributed to charge-transfer excitations to the 4f0 state. The intensity of the elastic peak increases when going from the systems with low Kondo temperature TK to those with high TK which is consistent with a Kondo scale behavior. By analyzing the scattering data, a controversial issue on the validity of a single-impurity Anderson model in heavy-fermion materials is addressed.
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| 7. |
- Butorin, S. M., et al.
(författare)
-
Resonant inelastic soft-x-ray scattering from valence-band excitations in 3d0 compounds
- 1997
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 55, s. 4242-4249
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Tidskriftsartikel (refereegranskat)abstract
- Ti and Mn Lα,Β x-ray fluorescence spectra of FeTiO3 and KMnO4 were measured with monochromatic photon excitation on selected energies across the L2,3 absorption edges. The resulting inelastic x-ray-scattering structures and their changes with varying excitation energies are interpreted within the framework of a localized, many-body approach based on the Anderson impurity model, where the radiative process is characterized by transitions to low-energy interionic-charge-transfer excited states. Sweeping the excitation energy through the metal 2p threshold enhances the fluorescence transitions to the antibonding states pushed out of the band of continuous states due to strong metal 3d–ligand 2p hybridization and matching the low-photon-energy satellites in the spectra. Based on the energy position of these charge-transfer satellites with respect to the recombination peak the effective metal 3d–ligand 2p hybridization strength in the ground state of the system can be estimated directly from the experiment.
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| 8. |
- Butorin, SM, et al.
(författare)
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Resonant inelastic soft-X-ray scattering at the 4d edge of Ce-based heavy-fermion materials
- 1999
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Ingår i: JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA. - 0368-2048. ; 103, s. 783-786
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Resonant X-ray scattering measurements were performed on CeB6, CeAl, gamma-Ce, and alpha-Ce at various incident-photon energies near the Ce 4d threshold. A pronounced inelastic scattering structure which has 4f character is observed at about 4 eV below th
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| 9. |
- Butorin, SM, et al.
(författare)
-
Resonant inelastic soft-x-ray scattering from valence-band excitations in 3d(0) compounds
- 1997
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - 0163-1829. ; 55:7, s. 4242-4249
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Ti and Mn L(alpha,beta) x-ray fluorescence spectra of FeTiO3 and KMnO4 were measured with monochromatic photon excitation on selected energies across the L(2,3) absorption edges. The resulting inelastic x-ray-scattering structures and their changes with v
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| 10. |
- Chowdhury, Susmita, et al.
(författare)
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Thermoelectric properties and electronic structure of Cr(Mo,V)Nx thin films studied by synchrotron and lab-based x-ray spectroscopy
- 2023
-
Ingår i: Physical Review B. - : AMER PHYSICAL SOC. - 2469-9950 .- 2469-9969. ; 108:20
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Tidskriftsartikel (refereegranskat)abstract
- Chromium-based nitrides are used in hard, resilient coatings and show promise for thermoelectric applications due to their combination of structural, thermal, and electronic properties. Here, we investigate the electronic structures and chemical bonding correlated to the thermoelectric properties of epitaxially grown chromium-based multicomponent nitride Cr(Mo,V)Nx thin films. The small amount of N vacancies causes Cr 3d and N 2p states to appear at the Fermi level and reduces the band gap in Cr0.51N0.49. Incorporating holes by alloying of V in N-deficient CrN results in an enhanced thermoelectric power factor with marginal change in the charge transfer of Cr to N compared with Cr0.51N0.49. Further alloying of Mo, isoelectronic to Cr, increases the density of states at the Fermi level due to hybridization of the (Cr, V) 3d and Mo 4d-N 2p states in Cr(Mo,V)Nx. This hybridization and N off-stoichiometry result in more metal-like electrical resistivity and reduction in Seebeck coefficient. The N deficiency in Cr(Mo,V)Nx also depicts a critical role in reduction of the charge transfer from metal to N site compared with Cr0.51N0.49 and Cr0.50V0.03N0.47. In this paper, we envisage ways for enhancing thermoelectric properties through electronic band engineering by alloying and competing effects of N vacancies.
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