La2USe3S2: A Serendipitously Grown Lanthanide/Actinide Chalcogenide from a Eutectic Halide Flux
La2USe3S2, exact composition La2USe2.96S2.04, crystallized from a reaction between USe2 and La2S3 in a molten CsCl/KCl eutectic flux and was characterized by single crystal X-ray diffraction. La2USe3S2 crystallizes in the orthorhombic space group Pnma in the U3S5 structure type with lattice parameters a = 12.3284(3) Å, b = 8.4028(2) Å, and c = 7.3452(2) Å. In La2USe3S2 all the anion sites have mixed S and Se occupancy and, henceforth, will be simply referred to as Q sites. The compound exhibits sigmoidal sheets built from LaQ8 (Q = S, Se) bicapped trigonal prisms that edge-share down the a-axis forming rectangular-shaped channels or tunnels. These tunnels are occupied by UQ6 (Q = S, Se) octahedra that edge-share to form infinite, one-dimensional chains running down the b-axis.
KeywordsLa2USe3S2 Single crystal Flux growth Chalcogenide
This research was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE-SC0018739.
- 4.Slovyanskikh VK, Kuznetsov NT (1990) Russ J Inorg Chem 35:447Google Scholar
- 5.Demoncy P, Khodadad P (1970) Ann Chim (Paris) 5:341–356Google Scholar
- 6.Potel M, Brochu R, Padiou J, Grandjean D (1972) C R Seances Acad Sci C 275:1419–1421Google Scholar
- 13.Bruker AXS, Inc. (2016) APEX3 version 2016.5-0 and SAINT + version 8.37A. Bruker AXS, Inc., MadisonGoogle Scholar
- 15.Sheldrick GM (2015) Acta Cryst A71:3–8Google Scholar
- 16.Sheldrick GM (2015) Acta Cryst C71:3–8Google Scholar
- 18.Marcon JP, Pascard R (1968) Rev Int Hautes Temp Refract 5:51Google Scholar
- 24.Slovyanskikh VK, Kusnetsov NT, Gracheva NV (1984) Russ J Inorg Chem 29(7):960–962Google Scholar