Precise magnetization measurement and magneto striction of dense-Kondo compound CeNi2Al5

The precise magnetization at 400 mK and magnetostriction at 1.2 K of a magn etic dense-Kondo compound CeNi2 Al-5 with a complex magnetic phase diagram are presented. Obvious anomalies corresponding to the phase transitions hav e been observed, involving stepwise changes of magnetization occurring at B -i = 3.52 T, B-e = 6.58 T, B-h = 5.67 T and B-f = 6.36 T. At these fields, stepwise changes of magnetostriction are also observed. Only the field Bi i ncreases with increasing temperature, contrary to the other transition fiel ds. We contend that not only the Kondo effect but also magnetoelastic and/o r quadrapolar effects must be taken into account to explain these complex p hase transitions. (C) 2001 Elsevier Science B.V. All rights reserved.