Impurity doping to molecular spin ladders: Magnetic properties of p-EPYNN+· [Ni(dmit)2]-1−x[Au(dmit)2]-x

We studied impurity effects on the magnetic properties of p-EPYNN+ · [Ni(dmit)2]-(p-EPYNN+=p-N)-ethylpyridinium nitronylnitroxide and [Ni(dmit)2] (dmit=1,3-dithiol-2-thione-4,5-dithiolate), whose crystal involved a molecular spin ladder of [Ni(dmit)2]− sandwiched by side-by-side and head-to-tail stacking chains of p-EPYNN+, by means of partial replacement of paramagnetic [Ni(dmit)2]− with non-magnetic [Au(dmit)2]−. In the solid solutions, p EPYNN+· [Nidmit)2]-1−x[Au(dmit)2]-x, an increase in x results in an increase of paramagnetic lattice defects on the spin ladder of [Ni(dmit)2]−, which become pathes of an antiferromagnetic interaction between the ferromagnetic chains of p-EPYNN+.