High-field magnetization has been examined for valence fluctuating Eu-based
compounds. Eu(Pd1-xPtx)(2)Si-2 (0 less than or equal to x less than or equ
al to 0.15) exhibits a universal relation between valence transition field
H-v and temperature, which suggests a single energy scale associated with t
he valence transition. Substitution of Ge for Si in EuPd2Si2 lowers H-v mor
e strongly. However, this valence transition is smeared due to a concentrat
ion fluctuation. (C) 1999 Elsevier Science B.V. All rights reserved.