Authors: Funda Ersoy ATALAY, Ali BAYRI, Hüseyin GENCER
Abstract: Some of the first transition metal alloys show first--order antiferromagnetic phase transitions as a function of alloy concentration. The antiferromagnetism of materials can be classified into three different classes: type I, type II and type III. Although the neutron diffraction studies give information about the antiferromagnetism, it does not say anything about the type of magnetism. So, in order to understand the type of magnetism, one must perform magnetic diffuse scattering. Recently, we proposed that the square lattice may have a double--Q structure as well as single--Q . We showed that the alloying may cause a first order antiferromagnetic phase transition between these two structures. In order to show that this is the case, we will perform the magnetic diffuse scattering, and give more evidence that the alloying play the dominant role in this phase transition.