Materials Data on KTl(CoSe)4 by Materials Project

Abstract

KTl(CoSe)4 is alpha bismuth trifluoride-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. K1+ is bonded in a body-centered cubic geometry to eight equivalent Se2- atoms. All K–Se bond lengths are 3.41 Å. Co+1.50+ is bonded to four Se2- atoms to form a mixture of edge and corner-sharing CoSe4 tetrahedra. There are two shorter (2.34 Å) and two longer (2.35 Å) Co–Se bond lengths. Tl1+ is bonded in a body-centered cubic geometry to eight equivalent Se2- atoms. All Tl–Se bond lengths are 3.42 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to four equivalent Co+1.50+ and four equivalent Tl1+ atoms. In the second Se2- site, Se2- is bonded in a 8-coordinate geometry to four equivalent K1+ and four equivalent Co+1.50+ atoms.