ic500599d_si_001.cif (53.74 kB)
Synthesis and Characterization of Two Quaternary Uranium Tellurides, RbTiU3Te9 and CsTiU3Te9
dataset
posted on 2014-08-04, 00:00 authored by Matthew D. Ward, Adel Mesbah, Minseong Lee, Christos D. Malliakas, Eun Sang Choi, James A. IbersBlack crystals of
RbTiU3Te9 and CsTiU3Te9 have been synthesized at 1223 and 1173 K, respectively, by high-temperature
solid-state routes. These compounds crystallize in a new structure
type in space group C2h2-P21/m of the monoclinic system. The structure,
which is similar to that of CsTiUTe5, consists of UTe2 layers connected into a three-dimensional framework by TiTe6 octahedra. The expanded UTe2 layers leave channels
that are filled by Rb or Cs atoms. Single-crystal resistivity measurements
on CsTiU3Te9 are consistent with semiconducting
behavior; the calculated activation energy is 0.30(1) eV. X-ray photoelectron
spectroscopic measurements on CsTiU3Te9 indicate
that the compound contains U4+. From single-crystal magnetic
measurements, CsTiU3Te9 is consistent with antiferromagnetic
coupling between magnetic U atoms. The very low value of the effective
magnetic moment of 0.56(2) μB is believed to arise
from a coexistence of magnetic and nonmagnetic U atoms.