Materials Data on NaEuSe2 by Materials Project

Abstract

NaEuSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with six equivalent NaSe6 octahedra, edges with four equivalent NaSe6 octahedra, and edges with eight equivalent EuSe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.99 Å) and four longer (3.03 Å) Na–Se bond lengths. Eu3+ is bonded to six Se2- atoms to form EuSe6 octahedra that share corners with six equivalent EuSe6 octahedra, edges with four equivalent EuSe6 octahedra, and edges with eight equivalent NaSe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.99 Å) and four longer (3.03 Å) Eu–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two equivalent Na1+ and four equivalent Eu3+ atoms to form a mixture of corner and edge-sharing SeNa2Eu4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Se2- site, Se2- is bonded to four equivalent Na1+ and two equivalent Eu3+ atoms to form SeNa4Eu2 octahedra that share corners with six equivalent SeNa4Eu2 octahedra and edges with twelve SeNa2Eu4 octahedra. The corner-sharing octahedral tilt angles are 0°.