| 1. |
- Nyholm, R., et al.
(författare)
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The surface core-level shift of the Pd(100) single-crystal surface
- 1992
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Ingår i: Journal of Physics: Condensed Matter. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 4:1, s. 277-283
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Tidskriftsartikel (refereegranskat)abstract
- The surface core-level shift of the Pd(100) single-crystal surface has been measured from high-resolution Pd 3d core-level spectra. The surface atoms are found to have 0.44+or-0.03 eV lower binding energy than the bulk atoms. The result is compared with theoretical estimates.
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| 2. |
- Petrashov, V. T., et al.
(författare)
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Electric field effects and screening in mesoscopic bismuth wires
- 1991
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Ingår i: Journal of Physics Condensed Matter. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 3:Copyright 1992, IEE, s. 9705-11
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Tidskriftsartikel (refereegranskat)abstract
- Large time-independent conduction fluctuations were observed as a function of transverse electric field in thin (25 nm) and narrow (60 nm) bismuth wires. The conduction of leads far away from a gate capacitor was influenced by changes in the gate voltage. The effects are interpreted as being due to a variation in the Fermi wavelength caused by gate-induced changes in the charge concentration of the leads rather than an electrostatic Aharonov-Bohm-type interference. The screening of charge is strongly reduced in narrow wires
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| 3. |
- Sandell, A., et al.
(författare)
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THE INNER VALENCE REGION OF CO ADSORBED ON PD(100)
- 1994
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 26:19, s. 10659-10668
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Tidskriftsartikel (refereegranskat)abstract
- The inner valence region of CO/Pd(100) p(2square-root2 x square-root2)R45-degrees has been studied by angular resolved photoemission at the Pd 4d Cooper minimum, and with resonant Auger spectroscopy at photon energies corresponding to the C 1s and O 1s x-ray absorption (XA) maxima of the unoccupied parts of the 2pi*-Pd 4d hybrid (2pi(un)). Previously unobserved inner valence states are revealed in the direct photoemission and are compared with resonant Auger results. The interpretation and assignment of the different spectral features to different main final state configurations are based on energy, symmetry and intensity arguments, as well as comparisons with previous results.
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| 4. |
- Andersson, Staffan, 1952-, et al.
(författare)
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Thermal conductivity and heat capacity of amorphous SiO2 : pressure and volume dependence
- 1992
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Ingår i: Journal of Physics. - : Institute of Physics (IOP). - 0953-8984 .- 1361-648X. ; 4:29, s. 6209-6216
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Tidskriftsartikel (refereegranskat)abstract
- The thermal conductivity (lambda) and heat capacity per unit volume (rho-c(p)) of amorphous SiO2 have been measured under hydrostatic pressure up to 1 GPa at room temperature using a transient two-strip method. The thermal conductivity was found to decrease slightly with increasing pressure. For the volume dependence of lambda expressed by the Bridgman parameter, g = -(partial derivative ln lambda/partial derivative ln V)T, we obtained g = -1.5. The experimental value of g is discussed in conjunction with predicted g-values based on theoretical models of lambda(T). The specific heat capacity (c(p)) calculated from measured rho-c(p) was found to be almost constant with increasing pressure.
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| 5. |
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| 6. |
- Chen, W., et al.
(författare)
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Structure determination of Pt3Ti(111) by automated tensor LEED
- 1993
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 5, s. 4585-4594
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Tidskriftsartikel (refereegranskat)abstract
- An analysis of low-energy electron diffraction (LEED) I-V spectra from the clean Pt3Ti(111) surface was performed by comparing measured intensities with data calculated using an automated tensor LEED program, which employs a directed search optimization procedure. It was found that the topmost layer is pure Pt and that the other layers have the bulk composition. The first and second interlayer spacings are 2.23+or-0.03 AA and 2.21+or-0.03 AA respectively, corresponding to a contraction of 0.9% and 1.8% of the bulk value. The perpendicular buckling is 0.04 AA +or-0.05 AA in the top layer and 0.15 AA +or-0.04 AA in the second layer. The results are in full accordance with previous investigations of the physical and chemical properties of this surface.
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| 7. |
- Hammar, Mattias, 1961-, et al.
(författare)
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Scanning tunnelling microscopy studies of Pt80Fe 20(110)
- 1993
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Ingår i: Journal of Physics: Condensed Matter. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 5:18, s. 2837-2842
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Tidskriftsartikel (refereegranskat)abstract
- Results of scanning tunnelling microscopy (STM) show that two different kinds of surface structures coexist on the (110) surface of Pt 80Fe20. The predominant structure corresponds well to the missing row type (1*2) reconstruction previously observed on, for example Pt(110), whereas the minority domains show a faintly buckled structure with approximately (1*1) geometry. Based on the STM images, the authors propose that the two domains have different surface chemical compositions and correspond to two different metallurgical phases known for the PtFe system at this composition.
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| 8. |
- Hanson, Maj, et al.
(författare)
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The influence of magnetic anisotropy on the magnetization of small ferromagnetic particles
- 1993
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Ingår i: Journal of Physics: Condensed Matter. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 5, s. 725-732
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Tidskriftsartikel (refereegranskat)abstract
- The authors calculated the magnetization of small ferromagnetic particles with uniaxial anisotropy. The numerical data were compared with experimental results for a magnetic liquid consisting of small amorphous Fe 0.75C0.25 particles in decalin. From the comparison an anisotropy K approximately=3*105 J m-3 was estimated.
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| 9. |
- Karlsson, Krister, 1961-, et al.
(författare)
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Chemical shifts for monovalent, divalent and trivalent Cu compounds
- 1992
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Ingår i: Journal of Physics. - : Institute of Physics Publishing (IOPP). - 0953-8984 .- 1361-648X. ; 4:3, s. 895-909
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Tidskriftsartikel (refereegranskat)abstract
- The authors study the chemical shift of the Cu 2p core level for Cu 2O, CuO and NaCuO2, where Cu is formally monovalent, divalent and trivalent, respectively. They find that the binding energy increases with the valence, as expected, although the variation in the number of 3d electrons is small and the trivalent Cu atom is found to have a smaller net positive charge than the monovalent or divalent Cu. The origin of the calculated chemical shifts is analysed and the relation with the chemical valence is discussed.
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| 10. |
- Karlsson, Krister, 1961-, et al.
(författare)
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Shape of the Cu 2p core level photoemission spectrum for monovalent, divalent and trivalent Cu compounds
- 1992
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Ingår i: Journal of Physics. - : Institute of Physics Publishing (IOPP). - 0953-8984 .- 1361-648X. ; 4:11, s. 2801-2816
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Tidskriftsartikel (refereegranskat)abstract
- We calculate the shape of the 2p core level photoemission spectrum for Cu2O, CuO and NaCuO2, where Cu is formally mono-, di- and trivalent, respectively. Although the number of 3d electrons is similar in the three compounds, there is a large variation in the strength of the d9-like satellite and in the width of the main line. We relate the differences between Cu2O and CuO to the difference in the valence, while for NaCuO2 the detailed form of the hopping matrix elements is also found to be important. © 1992 IOP Publishing Ltd.
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