Materials Data on U3TiS6 by Materials Project
U3TiS6 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are three inequivalent U+3.33+ sites. In the first U+3.33+ site, U+3.33+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of U–S bond distances ranging from 2.74–2.80 Å. In the second U+3.33+ site, U+3.33+ is bonded to seven S2- atoms to form distorted US7 pentagonal bipyramids that share corners with two equivalent US7 pentagonal bipyramids, edges with four US7 pentagonal bipyramids, and edges with four equivalent TiS7 pentagonal bipyramids. There are a spread of U–S bond distances ranging from 2.69–2.78 Å. In the third U+3.33+ site, U+3.33+ is bonded to seven S2- atoms to form distorted US7 pentagonal bipyramids that share corners with two equivalent US7 pentagonal bipyramids, corners with four equivalent TiS7 pentagonal bipyramids, edges with two equivalent TiS7 pentagonal bipyramids, and edges with four US7 pentagonal bipyramids. There are a spread of U–S bond distances ranging from 2.70–2.80 Å. Ti2+ is bonded to seven S2- atoms to form distorted TiS7 pentagonal bipyramids that share corners with four equivalent US7 pentagonal bipyramids, edges with six US7 pentagonal bipyramids, and faces with two equivalent TiS7 pentagonal bipyramids. There are a spread of Ti–S bond distances ranging from 2.53–2.89 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to two equivalent U+3.33+ and two equivalent Ti2+ atoms. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to four U+3.33+ atoms. In the third S2- site, S2- is bonded to five U+3.33+ atoms to form distorted SU5 square pyramids that share corners with eight SU3Ti2 square pyramids and edges with six SU4Ti square pyramids. In the fourth S2- site, S2- is bonded to three U+3.33+ and two equivalent Ti2+ atoms to form a mixture of distorted corner and edge-sharing SU3Ti2 square pyramids. In the fifth S2- site, S2- is bonded to three U+3.33+ and two equivalent Ti2+ atoms to form SU3Ti2 square pyramids that share corners with eight SU5 square pyramids and edges with six SU3Ti2 square pyramids. In the sixth S2- site, S2- is bonded to four U+3.33+ and one Ti2+ atom to form a mixture of distorted corner and edge-sharing SU4Ti square pyramids.