Materials Data on Ba2HfS4 by Materials Project
Ba2HfS4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine S2- atoms. There are a spread of Ba–S bond distances ranging from 3.11–3.53 Å. Hf4+ is bonded to six S2- atoms to form corner-sharing HfS6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.48 Å) and two longer (2.57 Å) Hf–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to five equivalent Ba2+ and one Hf4+ atom to form distorted SBa5Hf octahedra that share corners with seventeen SBa5Hf octahedra, edges with eight equivalent SBa5Hf octahedra, and faces with four equivalent SBa4Hf2 octahedra. The corner-sharing octahedra tilt angles range from 0–54°. In the second S2- site, S2- is bonded to four equivalent Ba2+ and two equivalent Hf4+ atoms to form distorted SBa4Hf2 octahedra that share corners with fourteen SBa5Hf octahedra, edges with two equivalent SBa4Hf2 octahedra, and faces with eight SBa5Hf octahedra. The corner-sharing octahedra tilt angles range from 0–54°.