Schoenes, JWithers, RaymondHulliger, F2015-12-070304-8853http://hdl.handle.net/1885/23504Diamagnetic ThAsSe and ferromagnetic UAsSe display negative temperature coefficients of the electrical resistivity over extended temperature ranges. Electron-diffraction studies show that As-As dimerizations within the As layers cause this Kondo-like behavior in ThAsSe and do also contribute in UAsSe. We suggest that a coupling between neighboring As layers at the lowest temperatures may be at the origin of a second Kondo-like regime below ≈15 K.Keywords: Actinides; Dimerization; Electric conductivity; Electron diffraction; Ferromagnetic materials; Kondo effects; Lowest temperatures; Negative temperature coefficients; Temperature ranges; Uranium compounds Actinides; Dimerization; Kondo effect; Superstructures200710.1016/j.jmmm.2006.10.6722015-12-07