Evidence for a pressure-induced magnetic-nonmagnetic transition of Pr impurities in la

Abstract

The depression of the superconducting transition temperature of lanthanum due to the presence of praseodymium impurities shows a pronounced maximum as a function of pressure at 230 kbar. We conclude that the 4f2 shell of Pr delocalizes under such high pressure and hence demagnetizes in analogy to the familiar case of the 4f1 configuration of Ce impurities in La at low pressure. © 1981 The American Physical Society.