Overview of the U3TGe5 family with T=Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta and W: Nine new members, phase formation, stability, structural and physical properties and electronic structures

摘要

Nine new ternary uranium transition metal germanides U3TGe5 with T=V, Cr, Mn, Zr, Nb, Mo, Hf, Ta and W have been discovered, in addition to the previously reported compound for T= Ti. These ten intermetallics adopt the anti-CuHf5Sn3-type of structure (hexagonal, P6(3)/mcm, Z = 2). Scanning electron microscopy images, energy dispersive spectroscopy, differential thermal analyses and X-ray data refinements were employed for chemical, thermal and structural characterizations. For the purest samples, obtained for T= Ti, V and Cr, the investigation of the magnetic and transport properties were analyzed revealing the subsequent influence of the 3d metals on the ground-state properties. Ab initio calculations of the band structure of these three U3TGe5 compounds were performed, showing nested Fermi surface which may be associated to the presence of Dirac cones for the magnetically ordered compounds, Le. for T = Ti and V.