MAGNETISM OF TERNARY COMPOUNDS RE6FE13X - RE=PR, ND - X=CU, AG, AU, ZN, CD, AND HG

Novel compounds RE6Fe13X (X=Cu, Ag, Au, Zn, Cd, Hg) have been synthesi zed by arc melting (Cu, Ag, Au) or by reaction sintering (Zn, Cd, Hg), followed by heat treatment at 550 or 600-degrees-C up to 350 h in eva cuated silica capsules. From room temperature x-ray powder diffraction analyses the alloys were found to crystallize with the ordered Nd6Fe1 3Si type. The CuTie point of all the compounds is found to lie around room temperature. Due to their low magnetization values a ferrimagneti c coupling within the Fe sublattice is suggested. A canted RE-spin str ucture cannot be ruled out. Fe-57 Mossbauer spectra were recorded from the samples with X=Ag and Au. Additionally, Au-197 spectra were taken from the two Au-containing compounds. The Fe-57 spectra are composed of various subpatterns, originating from the different Fe sites and we re found to be essentially unaffected by the specific element RE and X . In all cases under investigation the spectra could only be fitted un der the assumption of an easy axis of magnetization lying within the b asal plane. The Au-197 spectra reveal that the Au atoms predominantely occupy the 4a site.