Hydrides of actinides, their magnetic, electronic, transport, and thermodynamic properties are discussed within a general framework of H impact on bonding, characterized by volume expansion, affecting mainly the 5states, and a charge transfer towards H, which influences mostly the 6and 7states. These general mechanisms have diverse impact on individual actinides, depending on the degree of localization of their 5states. Hydrogenation of uranium yields UHand UH, binary hydrides that are strongly magnetic due to the 5band narrowing and reduction of the 5-6hybridization.
View Article and Find Full Text PDFAnisotropy of bulk magnetic properties and magnetic structure studies of a TbPdIn single crystal by means of bulk magnetization methods and neutron diffraction techniques confirmed the antiferromagnetic order below the Néel temperature 29.5 K. The collinear magnetic structure of Tb magnetic moments aligned along the tetragonal-axis is characterized by a propagation vector= (1/4, 1/4, 1/2), yielding an equal-moment structure with alternating coupling between nearest as well as next-nearest Tb neighbors within the basal plane and antiferromagnetic coupling between the-axis neighbors.
View Article and Find Full Text PDFA new type of uranium binary hydride, UH, with the CaF crystal structure, was synthesized in a thin-film form using reactive sputter deposition at low temperatures. The material has a grain size of 50-100 nm. The lattice parameter a = (535.
View Article and Find Full Text PDFA single crystal of U3Fe2Ge7 was synthesized by the tin-flux method, and its structural and electronic properties were studied. The compound crystallizes in the orthorhombic crystal structure of La3Co2Sn7 type with two Wyckoff sites for the U atoms. U3Fe2Ge7 displays a ferromagnetic order below TC = 62 K.
View Article and Find Full Text PDFThe UFeB₄ phase present in different alloys of the B-Fe-U system was studied by powder X-ray diffraction (PXRD) and scanning electron microscopy complemented with energy-dispersive spectroscopy and electron backscattered diffraction (EBSD). The PXRD data showed that the ternary compound crystallized adopting essentially the YCrB₄-type structure. However, microstructural observations revealed that under high undercooling conditions the UFeB₄ phase exhibits a random distribution of defects parallel to, which are consistently associated with intense higher-order Laue zone rings in EBSD patterns.
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