We report the crystal structure and magnetic properties of new ternary actinide compounds. A series of compounds having AnPd5Al2 composition crystallize in the body-center tetragonal ZrNi2Al 5-type tetragonal structure (/4/mmm). Although the magnetic susceptibility of both compounds follows the Curie-Weiss behavior at high temperature, no magnetic phase transition was observed. UPd5Al 2 has a nonmagnetic ground state where the magnetic susceptibility saturates at low temperature, while NpPd5Al2 superconducts below 4.9 K as reported recently. Another new ternary uranium intermetallic compound U 2/3Pd2Al5 crystallizes in the hexagonal structure (P63/mmc) with the lattice parameters 4.3278 and c = 16.2870 Å. The composition analysis and the single crystal X-ray diffraction revealed the peculiar disordered structure where 1/3 of uranium atoms are replaced by three aluminum atoms. The similar structure is reported previously for the compound in U-Fe-Si system. Magnetization as well as specific heat measurements revealed a low temperature anomaly corresponding to the magnetic phase transition.
|ジャーナル||Journal of Optoelectronics and Advanced Materials|
|出版ステータス||Published - 2008 7月|
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