Materials Data on TmAgS2 by Materials Project

Abstract

TmAgS2 crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with four equivalent TmS6 octahedra, corners with three equivalent AgS5 trigonal bipyramids, edges with four equivalent TmS6 octahedra, and edges with six equivalent AgS5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 11–13°. There are a spread of Tm–S bond distances ranging from 2.69–2.74 Å. Ag1+ is bonded to five S2- atoms to form AgS5 trigonal bipyramids that share corners with three equivalent TmS6 octahedra, corners with eight equivalent AgS5 trigonal bipyramids, and edges with six equivalent TmS6 octahedra. The corner-sharing octahedra tilt angles range from 0–75°. There are a spread of Ag–S bond distances ranging from 2.70–2.83 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent Tm3+ and three equivalent Ag1+ atoms to form STm3Ag3 octahedra that share corners with four equivalent STm3Ag3 octahedra, corners with three equivalent STm3Ag2 trigonal bipyramids, edges with four equivalent STm3Ag3 octahedra, and edges with six equivalent STm3Ag2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 7–11°. In the second S2- site, S2- is bonded to three equivalent Tm3+ and two equivalent Ag1+ atoms to form distorted STm3Ag2 trigonal bipyramids that share corners with three equivalent STm3Ag3 octahedra, corners with eight equivalent STm3Ag2 trigonal bipyramids, and edges with six equivalent STm3Ag3 octahedra. The corner-sharing octahedra tilt angles range from 0–75°.