Neutron scattering experiments have been carried out on the heavy fermion antiferromagnetic (AFM) superconductor CePt 3 Si with T N = 2.2 K and T SC = 0.75 K. We observed clear AFM Bragg reflections with Q 0 = (001/2) below and above T SC , indicating microscopic coexistence of AFM order and heavy fermion superconductivity. The AFM structure, of two interleaved ferromagnetic sublattices of local Ce 4f moments, has inversion symmetry under simultaneous space-time reversal. However, hybridization with Pt and Si breaks this degeneracy and a combination of these two competing effects may be relevant to an understanding of the simultaneous occurrence of superconductivity and AFM order. The observed magnetic moment 0.16(1) µ B /Ce is strongly reduced from the Curie-Weiss effective moment 2.54 µ B /Ce. Clear crystal field excitations at 1 and 24 meV were observed. The magnetic susceptibility can be well explained in a level scheme assuming the 7 ground state, 6 and 7 first and second excited states, respectively.

The synthesis of multifunctional magnetic nanoparticles (MF-MPs) is one of the most active research areas in advanced materials as their multifunctional surfaces allow conjugation of biological and chemical molecules, thus making it possible to achieve target-specific diagnostic in parallel to therapeutics. We report here a simple strategy to integrate in a one-step reaction several reactive sites onto the particles. The preparation of MF-MPs is based on their simultaneous modification with differently functionalized dopamine derivatives using simple solution chemistry. The formed MF-MPs show comparable magnetic properties to those of naked nanoparticles with almost unaltered particle size of around 25 nm. The different termini, amine, azide and maleimide functions, enable further functionalization of MF-MPs by the grafting-on approach. Michael addition, Cu(i) catalyzed « click » chemistry and amidation reactions are performed on the MF-MPs integrating subsequently 6-(ferrocenyl)-hexanethiol, horseradish peroxidase (HRP) and mannose.

The hansport properties of intermetallic compounds RCo2 (R = Pr, Nd, Sm, Gd-Lu, Sc and U) in the temperahue range f" 4.2 up to 1000 K were studied and different contributions were determined. In the non-magnetic compounds the spin fluchlation conhibution to the elechical resistivity, p,f U ( T / Z f ) z , and themal resistivity. Wsf c( (T/Trf). were found to follow Ihe theoretical predictions. The spin disorder wnuibution arising f" the scattering of conduction elecImns on 4f moments was deduced and found to be proportional to the de Gennes factor. It is shown that the spin fluctuations m responsible for the low-temperame features of the kmperature-dependent thermopower, whereas the high-temperarure behaviour is mainly determined by the density of states function.In the paramagnetic region near the Curie tempen", the critical fluctuations cause a considerable enhancement of the electrical resistivity of the magnetic RCq compounds, which is manifested by pronounced upturns in p versus T dependences.[9, 101. In the following the most important results are summarized.Low temperatures, T c l;f:Electrical resistivity: psf = AT2, with A proportional to TX7'. Magnetoresistance: ( A p / p ) s f is negative and proportional to the square of the appliedThermal resistivity: Wsf = cT, with c proportional to q:'.Thennopower: the situation is not yet clear. In some calculations a minimum below Elevated temperatures:Electrical resistivity: psj saturates somewhat above G,.. According to [9], for high values of the Stoner enhancement factor the resistivity can go through a maximum above i " , followed by a negative slope towards the high-temperature region.Thermal resistivity: Wsf passes a maximum around Tsf and decreases proportional to T-' at higher temperatures. magnetic field. cf has been predicted 1111.. .

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