Materials Data on KHg5Br11 by Materials Project
KHg5Br11 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of two KHg5Br11 sheets oriented in the (0, 1, 0) direction. K1+ is bonded in a 6-coordinate geometry to ten Br1- atoms. There are a spread of K–Br bond distances ranging from 3.50–4.07 Å. There are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to three Br1- atoms. There are a spread of Hg–Br bond distances ranging from 2.47–3.31 Å. In the second Hg2+ site, Hg2+ is bonded in a distorted linear geometry to six Br1- atoms. There are two shorter (2.47 Å) and four longer (3.53 Å) Hg–Br bond lengths. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Hg2+ atom. In the second Br1- site, Br1- is bonded in a distorted single-bond geometry to one K1+ and one Hg2+ atom. In the third Br1- site, Br1- is bonded to two equivalent K1+ and four equivalent Hg2+ atoms to form corner-sharing BrK2Hg4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth Br1- site, Br1- is bonded in a distorted single-bond geometry to one K1+ and two Hg2+ atoms.