BaLn2Se4 (Ln = Er, Tm and Yb).

Area of Science:

• Solid State Chemistry
• Inorganic Chemistry
• Materials Science

Background:

• The CaFe2O4 structure type is a common motif for complex oxides and related compounds.
• Understanding the structural properties of rare-earth chalcogenides is crucial for developing new materials.

Purpose of the Study:

• To investigate the crystal structure of barium rare-earth tetraselenides (BaLn2Se4).
• To characterize the coordination environments and framework of these novel compounds.

Main Methods:

• Single-crystal X-ray diffraction was used to determine the crystal structure.
• Analysis of atomic coordination and polyhedral arrangements.

Main Results:

• Compounds BaLn2Se4 (Ln = Er, Tm, Yb) crystallize in the orthorhombic Pnma space group, adopting the CaFe2O4 structure type.
• A 3D framework of corner- and edge-sharing LnSe6 octahedra forms channels.
• Barium atoms are coordinated by eight Se atoms in a bicapped trigonal prism and reside within these channels.

Conclusions:

• The BaLn2Se4 compounds exhibit a robust 3D channel structure.
• The specific coordination of rare-earth and barium atoms dictates the overall framework architecture.
• This structural motif offers potential for further materials design and property tuning.