Materials Data on Hg3Pd8Se9 by Materials Project
Pd8Hg3Se9 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are three inequivalent Pd sites. In the first Pd site, Pd is bonded to one Hg and five Se atoms to form distorted PdHgSe5 octahedra that share a cornercorner with one SeHgPd3 tetrahedra and edges with two equivalent PdHgSe5 octahedra. The Pd–Hg bond length is 2.89 Å. There are four shorter (2.55 Å) and one longer (2.65 Å) Pd–Se bond lengths. In the second Pd site, Pd is bonded in a 6-coordinate geometry to two Hg and four Se atoms. There are one shorter (2.85 Å) and one longer (2.98 Å) Pd–Hg bond lengths. There are a spread of Pd–Se bond distances ranging from 2.53–2.58 Å. In the third Pd site, Pd is bonded in a 6-coordinate geometry to one Hg and five Se atoms. The Pd–Hg bond length is 2.76 Å. There are a spread of Pd–Se bond distances ranging from 2.53–3.04 Å. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a 5-coordinate geometry to four Pd and one Se atom. The Hg–Se bond length is 2.65 Å. In the second Hg site, Hg is bonded in a 4-coordinate geometry to four equivalent Pd atoms. There are four inequivalent Se sites. In the first Se site, Se is bonded in a 4-coordinate geometry to four Pd atoms. In the second Se site, Se is bonded in a 6-coordinate geometry to six Pd atoms. In the third Se site, Se is bonded to four Pd atoms to form distorted SePd4 trigonal pyramids that share corners with three equivalent SeHgPd3 tetrahedra, corners with three equivalent SePd4 trigonal pyramids, and edges with two equivalent SePd4 trigonal pyramids. In the fourth Se site, Se is bonded to three Pd and one Hg atom to form SeHgPd3 tetrahedra that share a cornercorner with one PdHgSe5 octahedra and corners with six equivalent SePd4 trigonal pyramids. The corner-sharing octahedral tilt angles are 76°.