| Records |
| Author |
Tovar, M.; Sereni, J.G.; Pedrazzini, P.; Caneiro, A.; Prado, F.; Butera, A.; Causa, M.T. |
| Title |
Magnetization and specific heat of La doped Sr2FeMoO6 |
Type |
Journal Article |
| Year |
2004 |
Publication |
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
272 |
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Pages |
857-858 |
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| Abstract |
We present high-temperature magnetization and low-temperature specific heat measurements performed on the electron doped double perovskite Sr1.7La0.3FeMoO6. We have obtained the electronic contribution to C-p, gamma = 11.5(5) mJ/mol K-2. The electronic susceptibility, derived from the magnetic measurements in the paramagnetic regime (T > T-c = 390K), was chi(e)(0) =(4.9 +/- 1.5) x 10(-4) emu/mol. Anti ferromagnetic coupling between localized and itinerant moments was inferred from the data, with a coupling constant lambda = -(475 +/- 50)mol/emu, that results in a ferromagnetic-like Curie-Weiss susceptibility with Theta = 390(5) K. These results are compared with those obtained for the undoped material. (C) 2003 Published by Elsevier B.V. |
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0304-8853 |
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ISI:000222236700045 |
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BT @ hernan @ |
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63 |
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KAPPLER, J.P.; SCHMERBER, G.; SERENI, J.G. |
| Title |
CERIUM MAGNETIC-BEHAVIOR IN CE(PD,M) WITH M = CO, NI, RH, IR, PT, CU, AG AND AU |
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Journal Article |
| Year |
1988 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
76-7 |
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185-186 |
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0304-8853 |
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ISI:A1988T046300057 |
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no |
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BT @ hernan @ |
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124 |
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Sereni, J.G.; Nieva, G.; Kappler, J.P. |
| Title |
ANOMALOUS CRYSTAL-FIELD EFFECTS IN THE SPECIFIC-HEAT OF CE-HEAVY FERMION COMPOUNDS |
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Journal Article |
| Year |
1987 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
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63-64 |
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101-103 |
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0304-8853 |
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ISI:A1987G356900031 |
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no |
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BT @ hernan @ |
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128 |
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Sereni, J.G.; Nieva, G.; Huber, J.G.; Braun, E.; Oster, F.; Bruck, E.; Roden, B.; Wohlleben, D. |
| Title |
Evidence for 4f-instability of dilute terbium in thorium |
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Journal Article |
| Year |
1987 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
63-64 |
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597-599 |
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We have measured the specific heat of dilute Th1?xTbx alloys (0.44 < x < 2.15 a/o), which rises linearly between 0.4 and 0.9 K with a slope of ?C/T ? 450 mJ/K2molTb followed by a Schottky anomaly with a maximum near 3.8 K. The high temperature ??T product was found to be 4% lower than that of Tb3+. The resistivity shows no minimum at low temperatures. Discussion is made in terms of non-integral valence of Tb. |
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0304-8853 |
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ISI:A1987G356900173 |
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no |
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BT @ hernan @ |
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129 |
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Betancourth, D.; Facio, J.I.; Pedrazzini, P.; Jesus, C.B.R.; Pagliuso, P.G.; Vildosola, V.; Cornaglia, P.S.; García, D. J.; Correa, V. F. |
| Title |
Low Temperature magnetic properties of GdCoIn5 |
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Journal Article |
| Year |
2015 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
374 |
Issue |
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Pages |
744-747 |
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A comprehensive experimental and theoretical study of the low temperature properties of GdCoIn5 was performed. Specific heat, thermal expansion, magnetization and electrical resistivity were measured in good quality single crystals down to 4He temperatures. All the experiments show a second-order-like phase transition at 30 K probably associated with the onset of antiferromagnetic order. The magnetic susceptibility shows a pronounced anisotropy below T N with an easy magnetic axis perpendicular to the crystallographic ĉ-axis. Total energy GGA+U calculations indicate a ground state with magnetic moments localized at the Gd ions and allowed a determination of the Gd-Gd magnetic interactions. Band structure calculations of the electron and phonon contributions to the specific heat together with Quantum Monte Carlo calculations of the magnetic contributions show a very good agreement with the experimental data. Comparison between experiment and calculations suggests a significant anharmonic contribution to the specific heat at high temperature (View the MathML sourceT≳100K). |
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BT @ victor.correa @ |
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701 |
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Facio, J.I.; Betancourth, D.; Cejas Bolecek, N.R.; Jorge, G.A.; Pedrazzini, P.; Correa, V.F.; Cornaglia, P.S.; Vildosola, V.; García D.J. |
| Title |
Lattice specific heat for the RMIn5 (R=Gd, La,Y; M=Co, Rh) compounds: Non-magnetic contribution subtraction |
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Journal Article |
| Year |
2016 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
407 |
Issue |
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Pages |
406-4011 |
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BT @ victor.correa @ |
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730 |
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Franco, D.G.; Carbonio, R.E.; Kaul, E.E.; Nieva, G. |
| Title |
Tailoring the ground state of the ferrimagnet La2Ni(Ni1/3Sb2/3)O6 |
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Journal Article |
| Year |
2013 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
346 |
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Pages |
196-202 |
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Ferrimagnetic; Double perovskite; Magnetic frustration; Superexchange and super-superexchange interaction; Magnetic oxide |
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We report on the magnetic and structural properties of La2Ni(Ni1/3Sb2/3)O6 in polycrystal, single crystal and thin film samples. We found that this material is a ferrimagnet ( T c ≈ 100 K ) which possesses a very distinctive and uncommon feature in its virgin curve of the hysteresis loops. We observe that bellow 20 K it lies outside the hysteresis cycle, and this feature was found to be an indication of a microscopically irreversible process possibly involving the interplay of competing antiferromagnetic interactions that hinder the initial movement of domain walls. This initial magnetic state is overcome by applying a temperature dependent characteristic field. Above this field, an isothermal magnetic demagnetization of the samples yield a ground state different from the initial thermally demagnetized one. |
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0304-8853 |
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no |
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BT @ pedrazp @ |
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666 |
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| Author |
Vildosola, V.L.; Llois, A.M.; Weissmann, M.; Sereni, J.G. |
| Title |
Magnetic behaviour of Ce(Pd1-xMx) compounds (M = Rh, Ni and Ag) within the LDA approximation |
Type |
Journal Article |
| Year |
2001 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
236 |
Issue |
1-2 |
Pages |
6-8 |
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Ce intermetallic compounds have been intensively studied in the last few decades due to the large variety of behaviours they exhibit. In particular, two ways of demagnetizing Ce have been experimentally tried within the ferromagnetic systems Ce(Pd1-xMx), namely through electronic concentration variations (M=Rh) and volume reductions (M=Ni). On the other hand, when Pd is substituted by Ag, a transformation from a ferromagnetic to an antiferromagnetic ground state has been observed. In this work, we analyse the evolution of the magnetism of Ce in the above-mentioned family of compounds by calculating the spin contribution to magnetism that results from spin polarised LDA calculations. (C) 2001 Elsevier Science B.V. All rights reserved. |
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0304-8853 |
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ISI:000171670100004 |
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no |
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BT @ hernan @ |
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75 |
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Fraga, G.L.F.; Brandao, D.E.; Sereni, J.G. |
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Specific heat of X2MnSn (X = Co, Ni, Pd, Cu), X2MnIn (X = Ni, Pd) and Ni2MnSb Heusler compounds |
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Journal Article |
| Year |
1991 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
102 |
Issue |
1-2 |
Pages |
199-207 |
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Results of low-temperature specific heat measurements (1.5-8.0 K) on X2MnSn (X = Co, Ni, Pd, Cu), X2Mnln (X = Ni, Pd) and Ni2MnSb Heusler compounds are presented. All the compounds, except the cobalt based one, exibit a lattice spectrum anomaly described by an Einstein's term (soft-phonons). For all but one compound, the experimental values of the electronic specific heat coefficients are, at least, twice as big as the theoretical estimates. For two compounds it was possible to determine the magnetic effective field on Mn nuclei. |
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0304-8853 |
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ISI:A1991GX03900034 |
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no |
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BT @ hernan @ |
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117 |
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Sereni, J.G.; Trovarelli, O.; Schmerber, G.; Kappler, J.P. |
| Title |
Coexistence of magnetic order and heavy fermion behavior in Ce7X3 |
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Journal Article |
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1992 |
Publication |
Journal of Magnetism and Magnetic Materials |
Abbreviated Journal |
J. Magn. Magn. Mater. |
| Volume |
108 |
Issue |
1-3 |
Pages |
183-184 |
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Low temperature specific heat and magnetic susceptibility measurements on Ce7X3 (X = Rh, Ni) compounds are reported. Ce7Rh3 shows an onset of spontaneous magnetization at 7.2 K. About 40% of the expected R ln 2 entropy gain is found in the paramagnetic phase, related to a gamma(HT) = 1.1 J/K2 mol specific heat coefficient. In Ce7Ni3 an antiferromagnetic transition is observed at 1.7 K, superimposed to a large C(p)/T electronic contribution, described by a gamma(HT) = 0.9 J/K2 mol coefficient for T > 10 K. These results are interpreted in terms of the three different crystal sublattices of Ce. The entropy gain related to each transition allows to identify the behaviour of each sublattice. In the case of Ce7Ni3 one sublattice behaves as a heavy fermion system, with a value of C(p)/T = 3.3 J/K2 Ce at. Such a behaviour is confirmed under an applied magnetic field. |
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0304-8853 |
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ISI:A1992HH32900075 |
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BT @ hernan @ |
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113 |
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