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Substituent effects in aqueous solutions of carboxylate salts studied by x-ray absorption spectroscopy at the oxygen K-edge. J Chem Phys 2021; 155:014306. [PMID: 34241382 DOI: 10.1063/5.0053443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The present study aims at probing the influence of different substituents of sodium carboxylate salts R-COO-:Na+ in aqueous solutions, with R = H, CH3, C2H5, CH2Cl, CF3, and C6H5. X-ray absorption spectroscopy was used in the oxygen K-edge region to highlight the effect of R on the energy position of the O1s-to-πCOO* resonance of the carboxylate ion. Ab initio static exchange and ΔSCF calculations are performed and confirm the experimental observations. We qualitatively discuss the results on the basis of the polar properties of these groups as well as on the basis of the πCOO* orbital energy in the ground states, the oxygen 1s orbital ionization energy, and the O1s-to-πCOO* resonance energy.
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Morphology control in polymerised high internal phase emulsion templated via macro-RAFT agent composition: visualizing surface chemistry. Polym Chem 2018. [DOI: 10.1039/c7py01770g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of polymerized high internal phase emulsion (polyHIPE) materials have been prepared by using a water in oil emulsion stabilized by a macro-RAFT agent, 2-(butylthiocarbonothioylthio)-2-poly(styrene)-b-poly(acrylic acid), acting as a polymeric surfactant.
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Resonant inelastic x-ray scattering and photoemission measurement of O2: Direct evidence for dependence of Rydberg-valence mixing on vibrational states in O 1s → Rydberg states. J Chem Phys 2017; 147:044310. [DOI: 10.1063/1.4994895] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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4
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Core-multishell nanocarriers: Transport and release of dexamethasone probed by soft X-ray spectromicroscopy. J Control Release 2016; 242:64-70. [PMID: 27568290 DOI: 10.1016/j.jconrel.2016.08.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 08/16/2016] [Accepted: 08/23/2016] [Indexed: 11/26/2022]
Abstract
Label-free detection of core-multishell (CMS) nanocarriers and the anti-inflammatory drug dexamethasone is reported. Selective excitation by tunable soft X-rays in the O 1s-regime is used for probing either the CMS nanocarrier or the drug. Furthermore, the drug loading efficiency into CMS nanocarriers is determined by X-ray spectroscopy. The drug-loaded nanocarriers were topically applied to human skin explants providing insights into the penetration and drug release processes. It is shown that the core-multishell nanocarriers remain in the stratum corneum when applied for 100min to 1000min. Dexamethasone, if applied topically to human ex vivo skin explants using different formulations, shows a vehicle-dependent penetration behavior. Highest local drug concentrations are found in the stratum corneum as well as in the viable epidermis. If the drug is loaded to core-multishell nanocarriers, the concentration of the free drug is low in the stratum corneum and is enhanced in the viable epidermis as compared to other drug formulations. The present results provide insights into the penetration of drug nanocarriers as well as the mechanisms of controlled drug release from CMS nanocarriers in human skin. They are also compared to related work using dye-labeled nanocarriers and dyes that were used as model drugs.
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Visualizing chemical states and defects induced magnetism of graphene oxide by spatially-resolved-X-ray microscopy and spectroscopy. Sci Rep 2015; 5:15439. [PMID: 26481557 PMCID: PMC4612711 DOI: 10.1038/srep15439] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/02/2015] [Indexed: 11/23/2022] Open
Abstract
This investigation studies the various magnetic behaviors of graphene oxide (GO) and reduced graphene oxides (rGOs) and elucidates the relationship between the chemical states that involve defects therein and their magnetic behaviors in GO sheets. Magnetic hysteresis loop reveals that the GO is ferromagnetic whereas photo-thermal moderately reduced graphene oxide (M-rGO) and heavily reduced graphene oxide (H-rGO) gradually become paramagnetic behavior at room temperature. Scanning transmission X-ray microscopy and corresponding X-ray absorption near-edge structure spectroscopy were utilized to investigate thoroughly the variation of the C 2p(π*) states that are bound with oxygen-containing and hydroxyl groups, as well as the C 2p(σ*)-derived states in flat and wrinkle regions to clarify the relationship between the spatially-resolved chemical states and the magnetism of GO, M-rGO and H-rGO. The results of X-ray magnetic circular dichroism further support the finding that C 2p(σ*)-derived states are the main origin of the magnetism of GO. Based on experimental results and first-principles calculations, the variation in magnetic behavior from GO to M-rGO and to H-rGO is interpreted, and the origin of ferromagnetism is identified as the C 2p(σ*)-derived states that involve defects/vacancies rather than the C 2p(π*) states that are bound with oxygen-containing and hydroxyl groups on GO sheets.
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Selective Probing of the Penetration of Dexamethasone into Human Skin by Soft X-ray Spectromicroscopy. Anal Chem 2015; 87:6173-9. [DOI: 10.1021/acs.analchem.5b00800] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Site-specific intermolecular interaction in α-phase crystalline films of phthalocyanines studied by soft x-ray emission spectroscopy. J Chem Phys 2011; 135:034704. [DOI: 10.1063/1.3610530] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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[Thymoma with synchronous pulmonary metastasis; report of a case]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2010; 63:1090-1093. [PMID: 21066855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a resected case of thymoma with a solitary pulmonary metastasis. A 63-year-old woman had pointed out a solitary nodule in right lung field on chest X-ray. Computed tomography (CT) scan showed an anterior mediastinal tumor and a solitary lung nodule in the right lower lobe. Extended thymectomy and partial resection of right lung was performed. Pathological diagnosis showed an invasive thymoma (type B3) and a pulmonary metastasis. Post operative radiotherapy was administered and she is doing well 19 months following the resection. Thymoma with a solitary synclonous pulmonary metastasis is rare and is classified into Masaoka stage IVb. Generally, thymoma cases with distant metastasis are not indication for operation. But, if radical resection is possible, operation is recommended for good prognosis.
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Site-Dependent Spectral Shifts in Core-to-π* Excitations of Pyridine Clusters. J Phys Chem A 2008; 112:9192-9. [DOI: 10.1021/jp802068h] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Abstract
The C 1s -->pi* transition in molecular benzene and benzene clusters is investigated by photoion yields at high energy resolution. The vibrationally resolved band shows the same shape in clusters as in the bare molecule, but it is redshifted by 50 meV in small clusters, i.e. near the threshold of cluster formation. This redshift increases to 70 meV with increasing cluster size. The results are assigned in comparison with ab initio calculations on model structures of dimers, trimers, and tetramers. These indicate that different carbon sites in the molecular moieties give rise to distinct spectral shifts, where carbon sites that are pointing to the pi-system of another molecule show a larger redshift than the other ones. Such structural properties are found in solid benzene, so that the gas-to-solid shift of C 1s -->pi* excited benzene is derived to be a redshift which is of the order of 100-180 meV.
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Photoionization of small krypton clusters in the Kr 3d regime: Evidence for site-specific photoemission. J Chem Phys 2005; 123:154304. [PMID: 16252945 DOI: 10.1063/1.2060709] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Kr 3d ionization energies of small, variable size krypton clusters are investigated by photoelectron spectroscopy, where the size regime of clusters with an average size N< or =30 is studied. Characteristic shifts in Kr 3d ionization energies to lower binding energies are found compared to the bare atom. These are also different from those of large krypton clusters. Moreover, we find evidence for photoionization of the krypton dimer. Its 3d ionization energy is barely shifted relative to the atomic value. Results from model calculations considering different isomers and cluster sizes as well as defect sites give evidence that the experimental results can be related to photoionization from different surface sites in variable size krypton clusters. This can be related to site-specific photoemission in small Kr clusters. The results are compared to size effects in Kr 3d near-edge features of variable size Kr clusters as well as recent results on Kr 3d photoionization of large Kr clusters.
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Core excitation in O3 localized to one of two symmetry-equivalent chemical bonds: molecular alignment through vibronic coupling. J Chem Phys 2005; 122:154303. [PMID: 15945631 DOI: 10.1063/1.1881192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Core excitation from terminal oxygen OT in O3 is shown to be an excitation from a localized core orbital to a localized valence orbital. The valence orbital is localized to one of the two equivalent chemical bonds. We experimentally demonstrate this with the Auger-Doppler effect which is observable when O3 is core excited to the highly dissociative OT1s(-1)7a1 1 state. Auger electrons emitted from the atomic oxygen fragment carry information about the molecular orientation relative to the electromagnetic-field vector at the moment of excitation. The data together with analytical functions for the electron-peak profiles give clear evidence that the preferred molecular orientation for excitation only depends on the orientation of one bond, not on the total molecular orientation. The localization of the valence orbital "7a1" is caused by mixing of the valence orbital "5b2" through vibronic coupling of antisymmetric stretching mode with b2 symmetry. To the best of our knowledge, it is the first discussion of the localization of a core excitation of O3. This result explains the success of the widely used assumption of localized core excitation in adsorbates and large molecules.
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Electronic structure of bases in DNA duplexes characterized by resonant photoemission spectroscopy near the Fermi level. PHYSICAL REVIEW LETTERS 2004; 93:086403. [PMID: 15447209 DOI: 10.1103/physrevlett.93.086403] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2004] [Indexed: 05/24/2023]
Abstract
The electronic structure of bases in DNA duplexes was investigated by resonant photoemission spectroscopy near the Fermi level, in order to specify charge migration mechanisms. We observed a kinetic energy shift of N-KLL Auger electrons and an intensity enhancement of valence electrons on the resonant photoemission spectra for both poly(dG).poly(dC) and poly(dA).poly(dT) DNAs. These directly show the localized unoccupied states of the bases. We conclude that the charge hopping model is pertinent for electric conduction in a DNA duplex, when electrons pass through the unoccupied states.
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Abstract
Cluster size effects in core excitons below the N 1s ionization energy of nitrogen clusters are reported in the energy regime 405-410 eV. These results are compared to the molecular Rydberg states as well as the corresponding bulk excitons of condensed nitrogen. The experimental results are assigned using ab initio calculations. It is found that the lowest excitons (N 1s-->3ssigma and N 1s-->3ppi) are blueshifted relative to the molecular Rydberg transitions, whereas others (N 1s-->3dpi and N 1s-->4ppi) show a redshift. Results from ab initio calculations on (N(2))(13) clearly indicate that the molecular orientation within a cluster is critical to the spectral shift, where bulk sites as well as inner- and outer-surface sites are characterized by different inner-shell absorption energies. These results are compared to the experimental spectra as well as previous work on site-selectively excited atomic van der Waals clusters, providing an improved spectral assignment of core exciton states in weakly bound molecular clusters and the corresponding condensed phase.
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Sulfur 1s excitation of S2 and S8: Core–valence- and valence–valence–exchange interaction and geometry-specific transitions. J Chem Phys 2002. [DOI: 10.1063/1.1436482] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Nuclear motion driven by the Renner–Teller effect as observed in the resonant Auger decay to the X̃2Π electronic ground state of N2O+. J Chem Phys 2001. [DOI: 10.1063/1.1377890] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Resonant X-ray emission spectra of K2Ni(CN)4 x H2O at the Ni K-edge. JOURNAL OF SYNCHROTRON RADIATION 2001; 8:404-406. [PMID: 11512795 DOI: 10.1107/s0909049500015570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2000] [Accepted: 10/27/2000] [Indexed: 05/23/2023]
Abstract
Resonant X-ray emission spectra were measured at the Ni K-edge for a planar low-spin nickel complex K2Ni(CN)4 x H2O. In the Ni Kbeta emission spectra, a resonant X-ray Raman scattering was observed in the pre-edge region, showing linear energy dispersion of the emitted photon with the incident photon energy. No energy loss features corresponding to the ligand-to-metal charge-transfer (LMCT) was identified. The LMCT feature is characteristic of strongly correlated systems such as NiO; therefore, the LMCT effect proves to be significantly suppressed. This is consistent considering strong covalent character between low-lying pi* ligand and metal 3d (occupied) orbitals in low-spin nickel complexes.
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Mg and Al K-edge XAFS measurements with a KTP crystal monochromator. JOURNAL OF SYNCHROTRON RADIATION 2001; 8:351-353. [PMID: 11512777 DOI: 10.1107/s0909049500015995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2000] [Accepted: 10/30/2000] [Indexed: 05/23/2023]
Abstract
There has been a strong demand for monochromator crystals with a large lattice spacing in order to measure EXAFS spectra at the Mg and Al K-edges. We have introduced a pair of KTP crystal at BL1A of the UVSOR facility and examined its performance in the energy range between 1200 and 2000eV. This crystal monochromator can supply stable photon beams enough to measure the EXAFS spectra for the Mg and Al K-edges. Advantages of the KTP crystal are discussed in comparison with a YB66 crystal monochromator.
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The preferential expression of CD7 and CD34 in myeloid blast crisis in chronic myeloid leukemia. Blood 2000; 95:2188-9. [PMID: 10755822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
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24
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Polarized Ni K- and L-edge and S K-edge XANES study of [Ni(III)(mnt)2]1-. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:379-380. [PMID: 15263314 DOI: 10.1107/s0909049599002174] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 02/02/1999] [Indexed: 05/24/2023]
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25
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Tautomeric structure of N-salicylideneaniline derivatives studied by soft X-ray absorption spectroscopy and X-ray photoelectron spectroscopy. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:781-783. [PMID: 15263457 DOI: 10.1107/s0909049598017075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/1998] [Accepted: 12/09/1998] [Indexed: 05/24/2023]
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26
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Strong metal-to-ligand charge transfer bands observed in Ni K- and L-edge XANES of planar Ni complexes. JOURNAL OF SYNCHROTRON RADIATION 1999; 6:376-378. [PMID: 15263313 DOI: 10.1107/s0909049599001338] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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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Present Status of the UVSOR Facility - 1997. JOURNAL OF SYNCHROTRON RADIATION 1998; 5:1166-1169. [PMID: 15263779 DOI: 10.1107/s0909049597018311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 11/28/1997] [Indexed: 05/24/2023]
Abstract
The UVSOR has been operational for nearly 14 years. In recent years, improvements to accelerators and beamlines have been carried out to obtain better performance and new scientific achievements. For example, a new type of helical undulator and a resonance transverse kicker were installed into the straight sections of the storage ring, and about one-third of the beamlines were upgraded by installing new monochromators and an interferometer. In addition, instruments and equipment were improved for research studies, with many interesting results. The most up-to-date information of the UVSOR facility is presented.
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Electron-impact core excitation of SF6. I. S 2p, S 2s, and F 1s spectroscopy. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1995; 52:4665-4677. [PMID: 9912806 DOI: 10.1103/physreva.52.4665] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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32
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Dissociation dynamics of core-excited BF3 probed by the photoelectron—photoion—photoion coincidence. Chem Phys Lett 1995. [DOI: 10.1016/0009-2614(95)00382-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Experimental and theoretical studies of the (C 1s−1,π*)3Π state of CO: Momentum transfer dependence and vibrational structure. J Chem Phys 1994. [DOI: 10.1063/1.467923] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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35
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Observation of Rydberg-valence mixing in high-resolution symmetry-resolved oxygen K-edge spectra of O2. PHYSICAL REVIEW LETTERS 1994; 72:3961-3964. [PMID: 10056344 DOI: 10.1103/physrevlett.72.3961] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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36
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Electronic structure of the local-singlet insulator NaCuO2. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:7193-7204. [PMID: 10009456 DOI: 10.1103/physrevb.49.7193] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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37
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Origin of the band gap in the negative charge-transfer-energy compound NaCuO2. PHYSICAL REVIEW LETTERS 1991; 67:1638-1641. [PMID: 10044206 DOI: 10.1103/physrevlett.67.1638] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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38
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Cu K-edge x-ray-absorption near-edge structure and electronic structure of Nd2-xCexCuO4-y and La2-xSrxCuO4. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 41:131-137. [PMID: 9992746 DOI: 10.1103/physrevb.41.131] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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39
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Ru L edge x‐ray absorption studies of the electronic structure of Ru3(CO)12 adsorption and the formation of Ru–Cu bimetallics on Cu(111). J Chem Phys 1988. [DOI: 10.1063/1.454628] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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