ic8b01314_si_001.pdf (194.19 kB)
Synthesis, Structure, and Electrical Properties of the Single Crystal Ba8Cu16As30
journal contribution
posted on 2018-07-11, 18:56 authored by Kaya Wei, Artem R. Khabibullin, Dean Hobbis, Winnie Wong-Ng, Tieyan Chang, SuYin G. Wang, Igor Levin, Yu-Sheng Chen, Lilia M. Woods, George S. NolasSingle
crystals of clathrate-I Ba8Cu16As30 have been synthesized and their structure and electronic properties
determined using synchrotron-based X-ray diffraction and first-principles
calculations. The structure is confirmed to be Pm3̅n (No. 223), with lattice parameter a = 10.4563(3) Å, and defined by a tetrahedrally bonded
network of As and Cu that forms two distinct coordination polyhedra,
with Ba residing inside these polyhedra. All crystallographic positions
are fully occupied with no vacancies or superstructure with the Cu
atoms, while occupying all framework sites in the network, exhibiting
a preference for the 6c site. Agreement between the experimental and
theoretically predicted structures was achieved after accounting for
spin–orbit coupling. Our calculated Fermi surface, electron
localization, and charge transfer, as well as a comparison with the
results for elemental As46, provide insight into the fundamental
properties of this clathrate-I material.