Materials Data on Na6MnSe4 by Materials Project
Na6MnSe4 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four Se2- atoms to form distorted NaSe4 tetrahedra that share corners with two equivalent MnSe4 tetrahedra, corners with eight equivalent NaSe4 tetrahedra, and an edgeedge with one MnSe4 tetrahedra. There are a spread of Na–Se bond distances ranging from 2.88–3.06 Å. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five Se2- atoms. There are a spread of Na–Se bond distances ranging from 2.96–3.34 Å. Mn2+ is bonded to four Se2- atoms to form MnSe4 tetrahedra that share corners with six equivalent NaSe4 tetrahedra and edges with three equivalent NaSe4 tetrahedra. There are three shorter (2.53 Å) and one longer (2.54 Å) Mn–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 7-coordinate geometry to six Na1+ and one Mn2+ atom. In the second Se2- site, Se2- is bonded in a 8-coordinate geometry to seven Na1+ and one Mn2+ atom.