Raman and magnetic susceptibility evidence for a structural transition in (Eu(1.5-x)PrxCe(0.5))Sr2Cu2NbO10 compounds

Understanding the unique role that Pr hybridization plays in promoting both the suppression of superconductivity and the onset of complex magnetism in high-T-c cuprates continues to be a dynamic area of research. Complex magn etic behavior is well known to occur in the (Pr1.5Ce0.5)Sr2Cu2MO10 (M = Nb Or Ta) compounds. Previously, two temperature-dependent transitions have be en identified through magnetic susceptibility studies for the series of sol id solutions (Eu1.5-x PrxCe0.5)Sr2Cu2NbO10 (0.0 less than or equal to x les s than or equal to 1.5). In this paper, we present new measurements of the Raman-active modes and the magnetic susceptibility for these latter compoun ds. The data indicate a discontinuity in concentration space at a Pr doping level of x = 1.0, that we interpret as the signature of a subtle phase tra nsition. Copyright (C) 1999 John Wiley & Sons, Ltd.