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Braghta, A., G. Schmerber, A. Derory, J. G. Sereni, and J. P. Kappler. "Magnetic and thermal properties of Ce2Pd2Sn." Journal of Magnetism and Magnetic Materials 320, no. 6 (2008): 1141–1145.
Abstract: X-ray diffraction, susceptibility and specific heat studies on ternary Ce2Pd2Sn intermetallic compound and on its isostructural nonmagnetic compound La2Pd2Sn are reported. On Ce2Pd2Sn in absence of magnetic field, we confirm the existence of two magnetic transitions at T-N = 4.8K (antiferromagnetic transition) and T-C = 2.2K (ferromagnetic transition) and the specific heat results, measured down to 0.5 K, allow to recognize the transition at 2.2K as a first-order transition. A description based on molecular field calculations for the S = 1/2 resonant level model leads to a characteristic Kondo T-K of about 3K. (C) 2007 Elsevier B.V. All rights reserved.
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Tovar, M., J. G. Sereni, P. Pedrazzini, A. Caneiro, F. Prado, A. Butera, and M. T. Causa. "Magnetization and specific heat of La doped Sr2FeMoO6." JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 272 (2004): 857–858.
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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Vildosola, V. L., A. M. Llois, M. Weissmann, and J. G. Sereni. "Magnetic behaviour of Ce(Pd1-xMx) compounds (M = Rh, Ni and Ag) within the LDA approximation." Journal of Magnetism and Magnetic Materials 236, no. 1-2 (2001): 6–8.
Abstract: 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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Kappler, J. P., G. Schmerber, and J. G. Sereni. "Magnetic and thermal properties of Ce5Rh3." Journal of Magnetism and Magnetic Materials 115, no. 2-3 (1992): 241–244.
Abstract: Magnetic susceptibility, high field magnetization and specific heat measurements on Ce5Rh3 are reported. Two antiferromagnetic transitions are observed at T(N)=4.5 K and T(N)'=2.6 K. The magnetization curve at 1.5 K reveals a nontrivial magnetic structure in this compound, with a saturation magnetization of 0.72mu(B). The high temperature Curie constant (0.64 emu K/mol), the Curie-Weiss constant (THETA(p)=-45 K) and the entropy related with the magnetic transitions (DELTAS(m)=0.8 R In 2) indicate the presence of a Kondo-type component in the ground state of Ce5Rh3.
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Sereni, J. G., and J. P. Kappler. "Magnetic and thermal properties of CeCu." Journal of Magnetism and Magnetic Materials 109, no. 2-3 (1992): 349–352.
Abstract: Magnetic susceptibility, high field magnetization and specific heat measurements on CeCu are presented. An antiferromagnetic transition is observed at T(N) = 313 K, with some evidences of low dimensionality of the order parameter. The saturation magnetization. M(s) = 1.16-mu(B), implies that the crystalline electric field (CEF) ground state doublet is strongly magnetic, in agreement with the low temperature Curie constant C = 0.46 emu K/mol. In the high temperature limit (T > 50 K), the obtained Curie constant is C = 0.65 emu K/mol, which suggests an overall CEF splitting larger than 200 K. The entropy gain at the magnetic transition is 72% of the expected R in 2. The missing entropy is related to a specific heat anomaly with a maximum at approximately 13 K, which is attributed to magnetic fluctuations in the Ce chains. The transition temperature and the high temperature broad maximum in the specific heat are weakly affected by an applied magnetic field of 1 T.
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Sereni, J. G., O. Trovarelli, G. Schmerber, and J. P. Kappler. "Coexistence of magnetic order and heavy fermion behavior in Ce7X3." Journal of Magnetism and Magnetic Materials 108, no. 1-3 (1992): 183–184.
Abstract: 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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Pureur, P., J. G. Sereni, and J. Schaf. "Specific heat and magnetic susceptibility in YNd alloys." Journal of Magnetism and Magnetic Materials 104, no. 3 (1992): 1632–1634.
Abstract: We report on the specific heat and dc magnetic susceptibility measurements of the YNd 4.5, 6.8 and 9.0 at % alloys. These systems present long-range SDW order just below the critical temperature. For temperatures well below T(C), the spin glass type of behavior is manifest. An interpretation is given in terms of a disorder- and frustration-induced breaking of the SDW coherence into small domains.
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Fraga, G. L. F., D. E. Brandao, and J. G. Sereni. "Specific heat of X2MnSn (X = Co, Ni, Pd, Cu), X2MnIn (X = Ni, Pd) and Ni2MnSb Heusler compounds." Journal of Magnetism and Magnetic Materials 102, no. 1-2 (1991): 199–207.
Abstract: 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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KAPPLER, J. P., G. SCHMERBER, and J. G. SERENI. "CERIUM MAGNETIC-BEHAVIOR IN CE(PD,M) WITH M = CO, NI, RH, IR, PT, CU, AG AND AU." Journal of Magnetism and Magnetic Materials 76-7 (1988): 185–186.
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Sereni, J. G., G. Nieva, and J. P. Kappler. "ANOMALOUS CRYSTAL-FIELD EFFECTS IN THE SPECIFIC-HEAT OF CE-HEAVY FERMION COMPOUNDS." Journal of Magnetism and Magnetic Materials 63-64 (1987): 101–103.
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