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Updated: Aug 2, 2025
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Published on: April 14, 2020
Cs2Ln3CuS8 (Ln = La-Nd, Sm-Tb): Synthesis, Crystal Structure, and Magnetic and Optical Properties
Tatiana A Pomelova1, Charlène Delacotte2, Natalia V Kuratieva1
1Nikolaev Institute of Inorganic Chemistry SB RAS, 3, Akad. Lavrentiev Ave., 630090 Novosibirsk, Russian Federation.
Abstract:
This work reports the preparation of new quaternary sulfides Cs2Ln3CuS8 (Ln = La-Nd, Sm-Tb), their original crystal and electronic structures, and their magnetic properties. The sulfides were prepared using a reactive flux method from mixtures of Ln2S3 (EuS), Cs2S6, Cu2S, and S. They crystallize in a new type of structure (C2/m space group) and exhibit a layer-like crystal structure, which is a hybrid of those of the ACe2CuS6 series (A = Cs, K) and that of K2CeCu2S4. The values of the optical band gap calculated by the Kubelka-Munk equation are in the range of 1.2-2.62 eV depending on the nature of the Ln ion. The Cs2Gd3CuS8 compound displays relatively great magnetic refrigerating properties at cryogenic temperature with the mass entropy change (-ΔSM) reaching 19.5 J kg-1 K-1 at 3.5 K for ΔH = 5 T.
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