| Abstract Scope |
In the last two decades growing research efforts have focused on the development of magnetocaloric materials. Materials that show a sizeable magnetocaloric effect near room temperature are excellently suited for magnetic cooling and energy conversion applications. For systems that show a ferromagnetic transition that is accompanied by latent heat a giant magnetocaloric effect is found. In the (Fe,Mn)2(P,X) compounds (X = As, Ge, Si) attention has focused on optimizing the magnetocaloric materials properties and on the fundamental understanding of the origin of the unusual magnetoelastic transition. Compositional tuning allows for a detailed control of the operating temperatures and performance characteristics. Synchrotron X-ray studies, combined with density functional theory calculations, provide a detailed insight in the nature of the giant magnetocaloric effect. They reveal information on subtle changes in the electronic charge redistribution, the element-specific magnetic moments and the phonon density of states across the ferromagnetic transition. |