Combined experimental and quantum chemical study of new complex boride magnets with three-dimensional magnetic networks

本课题采用实验和理论相结合的方法，一方面设计制备了Th7Fe3型和双钙钛矿型新型磁性硼化物，并对其进行了表征和理论分析。该项目的目标是潜在的磁体，即铁磁体、亚铁磁体或反铁磁体。实验和理论工作将首先集中在一些新的金属间化合物系列，MT6-Nt‘Nb3(M=3d磁活性元素；T=4d过渡金属；T’=5d过渡金属；n=1-6)，其中将研究具有大自旋-轨道耦合(T‘)的元素对磁性的影响。第二，随着寻找新的三元和四元成员，具有通式M2T6-Nb(M=早期过渡金属；T=4d过渡金属；T‘=磁性过渡金属；n=0-6)的双钙钛矿硼化物家族将被扩展，特别关注电和磁性能。在这两个体系中，理论将指导实验探索，目的是设计出尽可能好的功能材料。在这个项目中，凝聚态系统的实验和理论的结合为研究生和博士后提供了一个真正的跨学科问题--他们将清楚地了解不同的科学学科和模型如何影响其他领域，从而学习现代固态化学研究的实验和理论部分。

This project combines experiment and theory towards the designed preparation, subsequent characterization and theoretical analysis of new magnetic borides crystallizing with the Th7Fe3 structure type on the one hand and with the double perovskite-type on the other hand. The project targets potential magnets, i.e., ferromagnets, ferrimagnets or antiferromagnets. Experimental and theoretical efforts will first focus on some new intermetallic series, MT6-nT´nB3 (M = 3d magnetically active element; T = 4d transition metal; T´= 5d transition metal; n = 1 - 6), in which the effect of the elements with large spin-orbit-coupling (T´) on the magnetic properties will be studied. Second, the family of double perovskite boride with the general formula M2T6-nT´nB (M = early transition metal; T = 4d transition metal; T´= magnetically active transition metal; n = 0 - 6) will be extended with the search of new ternary and quaternary members, with a particular focus on electrical and magnetic properties. In the two systems theory will guide the experimental exploration, with the aim of designing the best possible functional material. The combination of experiment and theory for condensed matter systems in this project provides the graduate student and postdoctoral associate a truly interdisciplinary problem -- They will clearly learn how different scientific subjects and models impact other areas, thereby learning both experimental and theoretical components of research in modern solid-state chemistry.