Materials Data on UAsS by Materials Project
UAsS is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. U5+ is bonded in a 5-coordinate geometry to four equivalent As3- and five equivalent S2- atoms. All U–As bond lengths are 3.06 Å. There are four shorter (2.79 Å) and one longer (2.80 Å) U–S bond lengths. As3- is bonded to four equivalent U5+ and four equivalent As3- atoms to form distorted AsU4As4 hexagonal bipyramids that share corners with four equivalent AsU4As4 hexagonal bipyramids, corners with twelve equivalent SU5 square pyramids, edges with four equivalent AsU4As4 hexagonal bipyramids, edges with four equivalent SU5 square pyramids, and faces with four equivalent AsU4As4 hexagonal bipyramids. All As–As bond lengths are 2.73 Å. S2- is bonded to five equivalent U5+ atoms to form distorted SU5 square pyramids that share corners with twelve equivalent AsU4As4 hexagonal bipyramids, corners with four equivalent SU5 square pyramids, edges with four equivalent AsU4As4 hexagonal bipyramids, and edges with eight equivalent SU5 square pyramids.