Materials Data on Na2US3 by Materials Project
Na2US3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with six NaS6 octahedra, edges with six NaS6 octahedra, and edges with six equivalent US6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are four shorter (2.91 Å) and two longer (2.92 Å) Na–S bond lengths. In the second Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with two equivalent NaS6 octahedra, corners with four equivalent US6 octahedra, edges with four equivalent US6 octahedra, and edges with eight NaS6 octahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are two shorter (2.83 Å) and four longer (3.02 Å) Na–S bond lengths. In the third Na1+ site, Na1+ is bonded to six S2- atoms to form NaS6 octahedra that share corners with two equivalent NaS6 octahedra, corners with four equivalent US6 octahedra, edges with four equivalent US6 octahedra, and edges with eight NaS6 octahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of Na–S bond distances ranging from 2.87–3.04 Å. U4+ is bonded to six S2- atoms to form US6 octahedra that share corners with six NaS6 octahedra, edges with three equivalent US6 octahedra, and edges with nine NaS6 octahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of U–S bond distances ranging from 2.70–2.72 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to four Na1+ and two equivalent U4+ atoms to form a mixture of edge and corner-sharing SNa4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the second S2- site, S2- is bonded to four Na1+ and two equivalent U4+ atoms to form a mixture of edge and corner-sharing SNa4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–8°.