High pressure studies of a new ternary actinide compound, UV2Al20

A new uranium compound, UV2Al20, is reported. This CeCr2Al20-type structure compound (a=14.4775(5) Angstrom) exhibits a large interatomic U-U distance , d(u-u) = 6.34 Angstrom, well beyond the Hill limit. The morphology of thi s sample was examined by means of scanning electron microscopy (SEM) and en ergy dispersive spectroscopy (EDS). The susceptibility obeys the Curie-Weis s law in the temperature range of 80-300 K, with mu (eff)=2.3(3)mu (B)/f.u. No magnetic transitions were detected down to 1.7 K, as was supported by t he electrical resistivity measurements. The X-ray analysis determined that V/V-0 = 0.82 at 31.5 GPa with no crystallographic phase transition. The bul k modulus and the pressure derivative were derived as B-0 = 40(5) GPa and B -0' = 17(2), respectively. (C) 2001 Elsevier Science B.V. All rights reserv ed.