Structural disorder and magnetism in rare-earth (R) R117Co54+xSn112±y

摘要: Abstract The cubic R 117 Co 54+ x Sn 112± y compounds (  = La–Lu, except Pm, Eu, and Yb) have been synthesized characterized using X-ray diffraction magnetization measurements. existence of the with  = Ce, Pr, Sm, Gd, Tb, Dy has confirmed, while new  = Y, La, Nd, Ho, Er, Tm, Lu discovered. All studied phases adopt 57 112 -type crystal structures a giant cell  ∼ 30 A) when proper heat treatment regime was selected. lattice parameter decreases from La to Lu, in accordance lanthanide contraction indicating trivalent state for Ce 54.5 115.2 . Co/Sn compositional ratio increases size atoms decreases. A single investigation Gd 56.4 114.3 confirms extensive structural disorder, particularly around (1/2, 1/2, 1/2) location unit (4 b site). Such disorder leads an elongation thermal ellipsoids surrounding this location. magnetic measurements Tb indicate weak interactions non-collinear alignment moments ordered state. electrical resistivity shows interesting behavior change sign at T C d ρ /d parameter.