| 1. |
- Myneni, S., et al.
(författare)
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Spectroscopic probing of local hydrogen-bonding structures in liquid water
- 2002
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 14:8, s. L213-L219
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Tidskriftsartikel (refereegranskat)abstract
- We have studied the electronic structure of liquid water using x-ray absorption spectroscopy at the oxygen K edge. Since the x-ray absorption process takes less than a femtosecond, it allows probing of the molecular orbital structure of frozen, local geometries of water molecules at a timescale that has not previously been accessible. Our results indicate that the electronic structure of liquid water is significantly different from that of the solid and gaseous forms, resulting in a pronounced pre-edge feature below the main absorption edge in the spectrum. Theoretical calculations of these spectra suggest that this feature originates from specific configurations of water, for which the H-bond is broken on the H-donating site of the water molecule. This study provides a fingerprint for identifying broken donating H-bonds in the liquid and shows that an unsaturated H-bonding environment exists for a dominating fraction of the water molecules.
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| 2. |
- Denecke, R, et al.
(författare)
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Beamline I511 at MAX II, capabilities and performance
- 1999
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Ingår i: JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA. - : ELSEVIER SCIENCE BV. - 0368-2048. ; 103, s. 971-977
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The new undulator beamline I511 at MAX-lab, now under commissioning, has been optimized for X-ray emission and photoelectron spectroscopies. Using an SX-700 high flux monochromator the accessible photon energy range is from 90 eV to about 1500 eV. The per
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| 3. |
- Fohlisch, A, et al.
(författare)
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Franck-Condon breakdown in core-level photoelectron spectroscopy of chemisorbed CO
- 1999
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Ingår i: CHEMICAL PHYSICS LETTERS. - : ELSEVIER SCIENCE BV. - 0009-2614. ; 315:3-4, s. 194-200
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Tidskriftsartikel (refereegranskat)abstract
- The photon energy dependence of the vibrational fine structure in the Cls and Ols X-ray photoelectron main lines of chemisorbed CO on Ni(100) and Ru(0001) has been measured from 6 to 150 eV above the core-level thresholds. Significant deviations from the
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| 4. |
- Sundin, S, et al.
(författare)
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Imaging properties of beam line optics for undulator based third generation synchrotron facilities
- 1999
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Ingår i: REVIEW OF SCIENTIFIC INSTRUMENTS. - : AMER INST PHYSICS. - 0034-6748. ; 70:1, s. 14-17
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Beam line optics for synchrotron facilities are generally designed from geometric calculations wherein the bending magnet, undulator, or wiggler photon source is approximated by a high divergence point source. In this article we will, however, show that i
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| 5. |
- Triguero, L., et al.
(författare)
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Direct experimental measurement of donation/back-donation in unsaturated hydrocarbon bonding to metals
- 2000
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 122:49, s. 12310-12316
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Tidskriftsartikel (refereegranskat)abstract
- Using resonant and off-resonant X-ray emission spectroscopy, in combination with ground-state density functional calculations, we examine the electronic structure of chemisarbed ethylene and benzene on thr Cu(110) surface to investigate the suitability of the donation/back-donation bonding model given by Dewar(1) and Chart and Duncanson(2) (DCD) for the interaction of unsaturated hydrocarbons with metal surfaces. We give an experimental verification of the DCD model and find donation/back-donation to be twice as large for ethylene as for benzene. In particular, the degree of sigma-pi mixing (rehybridization) is found to correspond to the amount of donation/back-donation, which is put in relation to the aromatic and nonaromatic pi characters of benzene and ethylene, respectively.
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| 6. |
- Triguero, L, et al.
(författare)
-
Direct experimental measurement of donation/back-donation in unsaturated hydrocarbon bonding to metals
- 2000
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Ingår i: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY. - : AMER CHEMICAL SOC. - 0002-7863. ; 122:49, s. 12310-12316 Language: English
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Tidskriftsartikel (refereegranskat)abstract
- Using resonant and off-resonant X-ray emission spectroscopy, in combination with ground-state density functional calculations, we examine the electronic structure of chemisarbed ethylene and benzene on thr Cu(110) surface to investigate the suitability of
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| 7. |
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