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51.
Highly Axial Magnetic Anisotropy in a N3O5 Dysprosium(III) Coordination Environment Generated by a Merocyanine Ligand 下载免费PDF全文
Pramila Selvanathan Gang Huang Thierry Guizouarn Dr. Thierry Roisnel Dr. Guglielmo Fernandez‐Garcia Dr. Federico Totti Dr. Boris Le Guennic Dr. Guillaume Calvez Dr. Kévin Bernot Dr. Lucie Norel Prof. Stéphane Rigaut 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15222-15226
A spiropyran‐based switchable ligand isomerizes upon reaction with lanthanide(III) precursors to generate complexes with an unusual N3O5 coordination sphere. The air‐stable dysprosium(III) complex shows a hysteresis loop at 2 K and a very strong axial magnetic anisotropy generated by the merocyanine phenolate donor. 相似文献
52.
Inside Back Cover: Weak Ligand‐Field Effect from Ancillary Ligands on Enhancing Single‐Ion Magnet Performance (Chem. Eur. J. 36/2016) 下载免费PDF全文
53.
Magnetic domain structures of precipitation-hardened SmCo 2:17-type sintered magnets: Heat treatment effect 下载免费PDF全文
The typical magnetic domains of Sm(CObalFe0.25Cuo.07Zr0.02)7.4 magnets quenched through various heattreatment steps have been revealed by using magnetic force microscopy (MFM). For the specimens in which the nominal c-axis is perpendicular to the imaging plane, the domain configurations change from plate-like for the as-sintered magnet to corrugation and spike-like for the homogenized one, and then to a coarse and finally to a finer domain structure when isothermally aged at 830℃ and then annealed at 400℃. However, only plate-like domains can be detected on the surfaces with the nominal c-axis parallel to the imaging plane. The finer domain (so-called interaction domain) is a characteristic magnetic domain pattern of the SmCo 2:IT-type magnets with high coercivities. Domain walls in a zigzag shape are revealed by means of MFM in final bulk SraCo 2:17-type sintered magnets. 相似文献
54.
The design of the China Spallation Neutron Source (CSNS) low-energy beam transport (LEBT) line, which locates between the ion source and the radio-frequency quadrupole (RFQ), has been completed with the TRACE3D code. The design aims at perfect matching, primary chopping, a small emittance growth and sufficient space for beam diagnostics. The line consists of three solenoids, three vacuum chambers, two steering magnets and a pre-chopper. The total length of LEBT is about 1.74 m. This LEBT is designed to transfer 20 mA of H-pulsed beam from the ion source to the RFQ. An induction cavity is adopted as the pre-chopper.The electrostatic octupole steerer is discussed as a candidate. A four-quadrant aperture for beam scraping and beam position monitoring is designed. 相似文献
55.
M. Sasaki V. Dupuis J.-P. Bouchaud E. Vincent 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(3):469-479
We study the deviations from perfect memory in negative temperature cycle spin glass experiments. It is known that the a.c.
susceptibility after the temperature is raised back to its initial value is superimposed to the reference isothermal curve
for large enough temperature jumps ΔT (perfect memory). For smaller ΔT, the deviation from this perfect memory has a striking non monotonous behavior: the `memory anomaly' is negative for small ΔT's, becomes positive for intermediate ΔT's, before vanishing for still larger ΔT's. We show that this interesting behavior can be reproduced by simple Random Energy trap models. We discuss an alternative
interpretation in terms of droplets and temperature chaos.
Received 23 May 2002 Published online 14 October 2002
RID="a"
ID="a"e-mail: sasaki@ipno.in2p3.fr 相似文献
56.
C. Djurberg K. Jonason P. Nordblad 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,10(1):15-21
Experiments on the temperature and time dependence of the response function and the field cooled magnetisation of a Cu(Mn)
spin glass at temperatures below the zero field spin glass temperature are used to explore the non-equilibrium nature of the
underlying spin configuration. The results imply that a certain spin configuration is imprinted on the system as the temperature
is decreased at a constant cooling rate. The cooling rate governs the magnitude of the FC magnetisation ((H,T)). Any intermittent halt at a constant temperature, , imprints an extended spin configuration, a process that is reflected e.g. in a downward relaxation of . On continued cooling at the same rate, the magnitude of (T) remains at a lower level than that of a continuous cooling curve. These results are put into the context of the corresponding
behaviour of the response function as observed in measurements of the relaxation of the zero field cooled magnetisation.
Received 27 October 1998 and Received in final form 30 November 1998 相似文献
57.
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59.
J.A. Hodges P. Bonville A. Forget J.P. Sanchez P. Vulliet M. Rams K. Królas 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,33(2):173-181
Using 170Yb and 155Gd M?ssbauer measurements down to ∼ 0.03 K, we have examined the semiconducting pyrochlore Yb2Mo2O7 where the Mo intra-sublattice interaction is anti-ferromagnetic and the metallic pyrochlore Gd2Mo2O7 where this interaction is ferromagnetic. Additional information was obtained from susceptibility, magnetisation and 172Yb perturbed angular correlation measurements. The microscopic measurements evidence lattice disorder which is important in
Yb2Mo2O7 and modest in Gd2Mo2O7. Magnetic irreversibilities occur at 17 K in Yb2Mo2O7 and at 75 K in Gd2Mo2O7 and below these temperatures the rare earths carry magnetic moments which are induced through couplings with the Mo sublattice.
In Gd2Mo2O7, we observe the steady state Gd hyperfine populations at 0.027 K are out of thermal equilibrium, indicating that Gd and Mo
spin fluctuations persist at very low temperatures. Frustration is thus operative in this essentially isotropic pyrochlore
where the dominant Mo intra-sublattice interaction is ferromagnetic.
Received 13 January 2003 Published online 4 June 2003
RID="a"
ID="a"e-mail: hodges@drecam.saclay.cea.fr 相似文献
60.
Sigmund EE Calder ES Thomas GW Mitrović VF Bachman HN Halperin WP Kuhns PL Reyes AP 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2001,148(2):309-313
We have studied the temporal instability of a high field resistive Bitter magnet through nuclear magnetic resonance (NMR). This instability leads to transverse spin decoherence in repeated and accumulated NMR experiments as is normally performed during signal averaging. We demonstrate this effect via Hahn echo and Carr--Purcell--Meiboom--Gill (CPMG) transverse relaxation experiments in a 23-T resistive magnet. Quantitative analysis was found to be consistent with separate measurements of the magnetic field frequency fluctuation spectrum, as well as with independent NMR experiments performed in a magnetic field with a controlled instability. Finally, the CPMG sequence with short pulse delays is shown to be successful in recovering the intrinsic spin--spin relaxation even in the presence of magnetic field temporal instability. 相似文献