ic951641b_si_001.pdf (342.3 kB)
Synthesis and Structure of the Layered Thorium Telluride CsTh2Te6
journal contribution
posted on 1996-06-19, 00:00 authored by Jason A. Cody, James A. IbersThe compound CsTh2Te6 has
been synthesized at 800 °C by the reaction of Th with a
Cs2Te3/Te melt as a
reactive flux. The compound crystallizes in the space group
-Cmcm of
the orthorhombic system with two
formula units in a cell of dimensions a = 4.367(2)
Å, b = 25.119(10) Å, c = 6.140(3)
Å, and V = 673.5(5) Å3
at T = 113 K. The structure of
CsTh2Te6 has been determined from
single-crystal X-ray data. The structure
comprises infinite, two-dimensional double layers of
ThTe8-bicapped trigonal prisms. The structural motif
of the
trigonal prisms resembles that found in UTe2.
Cs+ cations, disordered equally over two
crystallographically
equivalent sites, separate the layers and are coordinated by eight Te
atoms at the corners of a rectangular
parallelepiped. Short Te−Te distances of 3.052(3) and
3.088(3) Å form linear, infinite, one-dimensional
chains
within the layers. Simple formalisms describe neither the Te−Te
bonding in the chain nor the oxidation state of
Th. The compound shows weak semiconducting behavior along the
Th/Te layers perpendicular to the Te−Te
chain.