Materials Data on NaLa2Se3 by Materials Project

Abstract

NaLa2Se3 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Na1+ is bonded to six equivalent Se2- atoms to form NaSe6 octahedra that share corners with six equivalent LaSe6 octahedra, edges with six equivalent NaSe6 octahedra, and edges with six equivalent LaSe6 octahedra. The corner-sharing octahedral tilt angles are 2°. All Na–Se bond lengths are 3.09 Å. La+2.50+ is bonded to six Se2- atoms to form LaSe6 octahedra that share corners with three equivalent NaSe6 octahedra, corners with three equivalent LaSe6 octahedra, edges with three equivalent NaSe6 octahedra, and edges with nine equivalent LaSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are three shorter (3.01 Å) and three longer (3.09 Å) La–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three equivalent Na1+ and three equivalent La+2.50+ atoms to form a mixture of corner and edge-sharing SeNa3La3 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the second Se2- site, Se2- is bonded to six equivalent La+2.50+ atoms to form a mixture of corner and edge-sharing SeLa6 octahedra. The corner-sharing octahedral tilt angles are 2°.