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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Pureur, P., G. L. Fraga, D. E. Brandao, R. Caudron, H. Safa, and G. Nieva. "Specific heat measurements in scandium-rare earth anisotropic spin glasses." Journal of Magnetism and Magnetic Materials 68, no. 2 (1987): 213–217.
Abstract: We report on specific heat measurements at low temperature of the anisotropic spin glass alloys ScDy 3 at%, ScEr 4.25 at% and ScEr 10 at%. We find that at the lowest temperature range the data indicate the occurrence of an anisotropy induced gap around zero frequency in the density of states of the magnetic excitations. Moreover, some of our specific heat curves present a maximum coinciding with Tg, raising thus the question of thermal signs for a spin glass phase transition in anisotropic systems.
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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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Sereni, J. G., G. Nieva, J. G. Huber, E. Braun, F. Oster, E. Bruck, B. Roden, and D. Wohlleben. "Evidence for 4f-instability of dilute terbium in thorium." Journal of Magnetism and Magnetic Materials 63-64 (1987): 597–599.
Abstract: 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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SERENI, J. G. "The role of “p-like†orbitals in Ce valence instabilities." Journal of Magnetism and Magnetic Materials 47-48, no. FEB (1985): 228–230.
Abstract: From the analysis of spectroscopical data of atomic Ce, the [f(dsp)] configuration is found to be the least energetic when the metallization enthalpy is taken into account. The p-character of the band in Ce IV compounds is discussed and the p-f hybridization proposed.
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