MAGNETIC PROPERTIES OF U1-xYxMnAl SYSTEM

Abstract

The magnetic measurements on U 1-x Y x MnAl system were performed in the 4–600 K temperature range and fields up to 70 kOe. YMnAl presents spin fluctuation characteristics due to manganese atoms with a Curie–Weiss type behavior over the T* temperature. The gradual substitution of uranium for yttrium leads to similar behavior evidencing higher molar Curie constants and supporting a contribution due to uranium atom. The effective magnetic moment on uranium positions is that of U 3+ ion (3.1μB) and is composition-independent. The spin fluctuating state of manganese is characterized by the effective magnetic moment of 3μB/ Mn atom. The intrinsic Mn moment order is discussed in the critical Mn – Mn separation term.