%0 Journal Article %T Low-temperature physical properties of single crystal alpha-US1.82 %+ Institut des Sciences Chimiques de Rennes (ISCR) %A Tran, V. H. %A Noel, H. %< avec comité de lecture %@ 0925-8388 %J Journal of Alloys and Compounds %I Elsevier %V 694 %P 1175--1181 %8 2017-02 %D 2017 %R 10.1016/j.jallcom.2016.10.098 %K coqblin-schrieffer model %K 350 degrees k %K uranium chalcogenides %K magnetic-properties %K thermodynamic properties %K heat-capacities %K magnetoresistance %K resistivity %K diffraction %K transition %Z Chemical SciencesJournal articles %X We have studied a single crystal of alpha-US1.82 by measuring the magnetization M, electrical resistivity rho, magnetoresistance MR and specific heat C-p. Our experimental data establish that alpha-US1.82 is an antiferromagnet with T-N = 35 K and the easy magnetization is along the c-axis. Low-temperature properties of alpha-US1.82 are characterized also by an enhanced Sommerfeld coefficient gamma = 47 mJ/molK(2) and meta magnetic transition at mu H-0(cr) = 5.5 T. The latter behaviour accompanies with a huge MR of 52 % and abrupt collapse in the gamma(H) dependence, pointing to magnetic field-induced change of both magnetic superzone boundaries and density of states at the Fermi level. The temperature dependence of magnetic specific heat below 20 K is found to follow a function of thermally activated magnons: C-mag alpha T-exp(n)(-Delta/k(B)T), with Delta/k(B) = 3.5-6.9 K and n = 1.5-2.0. The observed exponent values seem to suggest the coexistence of ferromagnetic and antiferromagnetic interactions or two-dimensional anti ferromagnetic arrangements of magnetic uranium moments. The MR and C-p data show evidence of short-range interactions in the temperature range T-N- 2T(N), presumably caused by non-stoichiometric character of compound. The specific heat behaviour is discussed invoking the Kondo state with Kondo temperature T-K similar to 15 K and crystal electric field effect with splitting energy of 150-190 K. (C) 2016 Elsevier B.V. All rights reserved. %G English %L hal-01475461 %U https://univ-rennes.hal.science/hal-01475461 %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ ENSC-RENNES %~ ISCR %~ STATS-UR1 %~ UR1-SPM %~ INC-CNRS %~ UR1-UFR-SPM %~ UR1-HAL %~ UR1-SDLM %~ TEST-UNIV-RENNES %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ TEST-HALCNRS %~ UR1-MMS %~ TEST2-HALCNRS