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DOE OSTI · 1652492

Materials Data on Hg6P4PbCl6 by Materials Project

Abstract

Hg6PbP4Cl6 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are two inequivalent Hg+1.33+ sites. In the first Hg+1.33+ site, Hg+1.33+ is bonded to two P1- and four Cl1- atoms to form HgP2Cl4 octahedra that share corners with eight HgP2Cl4 octahedra, corners with two PHg3P tetrahedra, edges with two equivalent PbCl6 octahedra, and edges with four equivalent HgP2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 8–85°. Both Hg–P bond lengths are 2.50 Å. There are a spread of Hg–Cl bond distances ranging from 2.95–3.27 Å. In the second Hg+1.33+ site, Hg+1.33+ is bonded to two P1- and four Cl1- atoms to form distorted HgP2Cl4 octahedra that share corners with eight HgP2Cl4 octahedra, corners with two PHg3P tetrahedra, edges with two equivalent PbCl6 octahedra, and edges with four equivalent HgP2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 8–85°. Both Hg–P bond lengths are 2.49 Å. There are a spread of Hg–Cl bond distances ranging from 2.91–3.24 Å. Pb2+ is bonded to six Cl1- atoms to form PbCl6 octahedra that share edges with twelve HgP2Cl4 octahedra. There are three shorter (2.79 Å) and three longer (3.10 Å) Pb–Cl bond lengths. There are four inequivalent P1- sites. In the first P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 68°. The P–P bond length is 2.20 Å. In the second P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 69°. In the third P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 71°. The P–P bond length is 2.21 Å. In the fourth P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 69°. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded to four Hg+1.33+ and one Pb2+ atom to form distorted ClHg4Pb square pyramids that share corners with nine ClHg4Pb square pyramids, corners with four PHg3P tetrahedra, edges with four ClHg4Pb square pyramids, and edges with two PHg3P tetrahedra. In the second Cl1- site, Cl1- is bonded to four Hg+1.33+ and one Pb2+ atom to form distorted ClHg4Pb square pyramids that share corners with nine ClHg4Pb square pyramids, corners with four PHg3P tetrahedra, edges with four ClHg4Pb square pyramids, and edges with two PHg3P tetrahedra.

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2020-05-02. Materials Data on Hg6P4PbCl6 by Materials Project. https://doi.org/10.17188/1652492

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