Materials Data on K3NbSe4 by Materials Project
K3NbSe4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of K–Se bond distances ranging from 3.29–3.93 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of K–Se bond distances ranging from 3.37–3.74 Å. Nb5+ is bonded in a tetrahedral geometry to four Se2- atoms. There are three shorter (2.42 Å) and one longer (2.43 Å) Nb–Se bond lengths. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 1-coordinate geometry to five K1+ and one Nb5+ atom. In the second Se2- site, Se2- is bonded in a 1-coordinate geometry to six K1+ and one Nb5+ atom. In the third Se2- site, Se2- is bonded to five K1+ and one Nb5+ atom to form edge-sharing SeK5Nb octahedra.