DOE OSTI2020
Th7S12 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are three inequivalent Th sites. In the first Th site, Th is bonded in a 9-coordinate geometry to nine S atoms. There are three shorter (2.79 Å) and six longer (3.08 Å) Th–S bond lengths. In the second Th site, Th is bonded in a 8-coordinate geometry to eight S atoms. There are a spread of Th–S bond distances ranging from 2.81–3.01 Å. In the third Th site, Th is bonded in a 8-coordinate geometry to eight S atoms. There are a spread of Th–S bond distances ranging from 2.76–3.01 Å. There are four inequivalent S sites. In the first S site, S is bonded to five Th atoms to form distorted STh5 trigonal bipyramids that share corners with five equivalent STh4 tetrahedra, corners with ten STh5 trigonal bipyramids, edges with two equivalent STh4 tetrahedra, and edges with eight STh5 trigonal bipyramids. In the second S site, S is bonded to five Th atoms to form distorted STh5 trigonal bipyramids that share corners with two equivalent STh4 tetrahedra, corners with thirteen STh5 trigonal bipyramids, edges with two equivalent STh4 tetrahedra, and edges with eight STh5 trigonal bipyramids. In the third S site, S is bonded to four Th atoms to form STh4 tetrahedra that share corners with four equivalent STh4 tetrahedra, corners with nine STh5 trigonal bipyramids, and edges with eight STh5 trigonal bipyramids. In the fourth S site, S is bonded to five Th atoms to form distorted STh5 trigonal bipyramids that share corners with two equivalent STh4 tetrahedra, corners with eleven STh5 trigonal bipyramids, edges with four equivalent STh4 tetrahedra, and edges with eight STh5 trigonal bipyramids.