References of "European Physical Journal B -- Condensed Matter"
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See detailCapturing intensive and extensive DFT/TDDFT molecular properties with machine learning
Pronobis, Wiktor; Sch utt, Kristof; Tkatchenko, Alexandre UL et al

in European Physical Journal B -- Condensed Matter (2018), 91

Machine learning has been successfully applied to the prediction of chemical properties of small organic molecules such as energies or polarizabilities. Compared to these properties, the electronic ... [more ▼]

Machine learning has been successfully applied to the prediction of chemical properties of small organic molecules such as energies or polarizabilities. Compared to these properties, the electronic excitation energies pose a much more challenging learning problem. Here, we examine the applicability of two existing machine learning methodologies to the prediction of excitation energies from time-dependent density functional theory. To this end, we systematically study the performance of various 2- and 3-body descriptors as well as the deep neural network SchNet to predict extensive as well as intensive properties such as the transition energies from the ground state to the rst and second excited state. As perhaps expected current state-of-the-art machine learning techniques are more suited to predict extensive as opposed to intensive quantities. We speculate on the need to develop global descriptors that can describe both extensive and intensive properties on equal footing. [less ▲]

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See detailLongitudinal polarization analysis in small-angle neutron scattering
Honecker, Dirk UL; Ferdinand, A.; Döbrich, Frank UL et al

in European Physical Journal B -- Condensed Matter (2010), 76(2), 209-213

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See detailTime-resolved nuclear spin-dependent small-angle neutron scattering from polarised proton domains in deuterated solutions
van den Brandt, B.; Glättli, H.; Grillo, I. et al

in European Physical Journal B -- Condensed Matter (2006), 49(2), 157-165

We have investigated the process of dynamic proton polarisation by means of time-resolved polarised small-angle neutron scattering (SANS) on frozen solutions of EHBA-CrV molecules in glycerol-water ... [more ▼]

We have investigated the process of dynamic proton polarisation by means of time-resolved polarised small-angle neutron scattering (SANS) on frozen solutions of EHBA-CrV molecules in glycerol-water mixtures as a function of the concentration of EHBA-CrV and for different degrees of deuteration of the solvent. In the EHBA-CrV complex, the spins of the 20 protons which surround the paramagnetic CrV can be oriented using the method of dynamic nuclear polarisation (DNP), thereby offering the possibility to create locally a nuclear spin-dependent contrast for SANS. The time constants which describe the build-up of polarisation around the paramagnetic centre and the subsequent diffusion of polarisation in the solvent were determined by analysing the temporal evolution of the nuclear polarisation, which in turn was obtained by fitting a core-shell model to the time-dependent SANS curves. The results on the spin dynamics obtained using the scattering function of a core-shell could be independently confirmed by evaluating the integrated SANS intensity. A thermodynamic one-centre model is presented which is able to reproduce the observed dependence of the proton polarisation times on the proton concentration of the solvent. [less ▲]

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See detailOn the influence of anisotropy on the magnetic small-angle neutron scattering of superparamagnetic particles
Michels, Andreas UL; Weissmüller, J.

in European Physical Journal B -- Condensed Matter (2002), 26

This paper presents a calculation of the magnetic small-angle neutron scattering cross-section resulting from a dilute ensemble of superparamagnetic particles exhibiting uniaxial magnetic anisotropy. We ... [more ▼]

This paper presents a calculation of the magnetic small-angle neutron scattering cross-section resulting from a dilute ensemble of superparamagnetic particles exhibiting uniaxial magnetic anisotropy. We focus on the two experimentally relevant scattering geometries in which the incident neutron beam is perpendicular or parallel to an applied magnetic field, and we discuss several orientations of the anisotropy axes with respect to the field. Magnetic anisotropy has no influence on the magnetic small-angle neutron scattering when the particles are mobile, as is the case e.g. in ferrofluids, but, when the particles are embedded in a rigid non-magnetic matrix and the orientations of the anisotropy axes are fixed, significant deviations compared to the case of negligible anisotropy are expected. For the particluar situation in which the anisotropy axes are parallel to the applied field, closed-form expressions suggest that an effective anisotropy energy or anisotropy-energy distribution can be determined from experimental scattering data. [less ▲]

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See detailA lower bound for the volume-averaged mean-square magnetostatic stray field
Michels, Andreas UL; Weissmüller, J.; Birringer, R.

in European Physical Journal B -- Condensed Matter (2002), 29

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