%A Ovchinnikov,Alexander
%A Bobev,Svilen
%D 2020
%J Frontiers in Chemistry
%C
%F
%G English
%K Flux growth,pnictides,crystal structure,electronic structure,Metal clusters
%Q
%R 10.3389/fchem.2019.00909
%W
%L
%M
%P
%7
%8 2020-January-10
%9 Original Research
%#
%! Ba-V-Sb and Ba-V-As
%*
%<
%T Exploration of Multi-Component Vanadium and Titanium Pnictides Using Flux Growth and Conventional High-Temperature Methods
%U https://www.frontiersin.org/articles/10.3389/fchem.2019.00909
%V 7
%0 JOURNAL ARTICLE
%@ 2296-2646
%X The flux growth method was successfully employed to synthesize millimeter-sized single crystals of the ternary barium vanadium pnictides Ba5V12As19+x (x ≈ 0.02) and Ba5V12Sb19+x (x ≈ 0.36), using molten Pb and Sb, respectively. Both compositions crystallize in space group P4̄3m and adopt a structure similar to those of the barium titanium pnictides Ba5Ti12Pn19+x (Pn = Sb, Bi), yet with a subtly different disorder, involving the pnictogen and barium atoms. Attempts to obtain an arsenide analog of Ba5Ti12Pn19+x using a Pb flux technique yielded binary arsenides. High-temperature treatment of the elements Ba, Ti, and As in Nb or Ta tubes resulted in side reactions with the crucible materials and produced two isostructural compositions Ba8Ti13−xMxAs21 (M = Nb, Ta; x ≈ 4), representing a new structure type. The latter structure displays fcc-type metal clusters comprised of statistically distributed Ti and M atoms (M = Nb, Ta) with multi-center and two-center bonding within the clusters, as suggested by our first-principle calculations.