6,929 research outputs found
Kondo effect and spin quenching in high-spin molecules on metal substrates
Using a state-of-the art combination of density functional theory and
impurity solver techniques we present a complete and parameter-free picture of
the Kondo effect in the high-spin () coordination complex known as
Manganese Phthalocyanine adsorbed on the Pb(111) surface. We calculate the
correlated electronic structure and corresponding tunnel spectrum and find an
asymmetric Kondo resonance, as recently observed in experiments. Contrary to
previous claims, the Kondo resonance stems from only one of three possible
Kondo channels with origin in the Mn 3d-orbitals, its peculiar asymmetric shape
arising from the modulation of the hybridization due to strong coupling to the
organic ligand. The spectral signature of the second Kondo channel is strongly
suppressed as the screening occurs via the formation of a many-body singlet
with the organic part of the molecule. Finally, a spin-1/2 in the 3d-shell
remains completely unscreened due to the lack of hybridization of the
corresponding orbital with the substrate, hence leading to a spin-3/2
underscreened Kondo effect.Comment: 5 pages, 2 figure
Viscoelastic vibration damping identification methods. Application to laminated glass.
Laminatedglass is composed of two glass layers and a thin intermediate PVB layer, strongly influencing PVB's viscoelastic behaviour its dynamic response. While natural frequencies are relatively easily identified even with simplified FE models, damping ratios are not identified with such an ease. In order to determine to what extent external factors influence dampingidentification, different tests have been carried out. The external factors considered, apart from temperature, are accelerometers, connection cables and the effect of the glass layers. To analyse the influence of the accelerometers and their connection cables a laser measuring device was employed considering three possibilities: sample without instrumentation, sample with the accelerometers fixed and sample completely instrumented. When the sample is completely instrumented, accelerometer readings are also analysed. To take into consideration the effect of the glass layers, tests were realised both for laminatedglass and monolithic samples. This paper presents in depth data analysis of the different configurations and establishes criteria for data acquisition when testing laminatedglass
Compromise Solutions for Bankruptcy Situations with References
This paper deals with bankruptcy situations in which in addition to the claims, an exogenously given reference point for the allocation of the estate is present.We introduce and analyse two types of compromise solutions and show that they coincide with the T value of two corresponding TU games.We apply our solutions to a real-life case of allocating university money to degree courses.bankruptcy;allocation;t-value;games
Localized basis sets for unbound electrons in nanoelectronics
It is shown how unbound electron wave functions can be expanded in a suitably
chosen localized basis sets for any desired range of energies. In particular,
we focus on the use of gaussian basis sets, commonly used in first-principles
codes. The possible usefulness of these basis sets in a first-principles
description of field emission or scanning tunneling microscopy at large bias is
illustrated by studying a simpler related phenomenon: The lifetime of an
electron in a H atom subjected to a strong electric field.Comment: 6 pages, 5 figures, accepted by J. Chem. Phys. (http://jcp.aip.org/
Anomalous Roughening of Viscous Fluid Fronts in Spontaneous Imbibition
We report experiments on spontaneous imbibition of a viscous fluid by a model
porous medium in the absence of gravity. The average position of the interface
satisfies Washburn's law. Scaling of the interface fluctuations provides a
dynamic exponent z \simeq 3, indicative of global dynamics driven by capillary
forces. The complete set of exponents clearly shows that interfaces are not
self-affine, exhibiting distinct local and global scaling, both for time
(b=0.64\pm 0.02, b* =0.33 \pm 0.03) and space (a=1.94 \pm 0.20, a_loc=0.94 \pm
0.10). These values are compatible with an intrinsic anomalous scaling
scenario.Comment: 4 pages, 5 figure
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