Materials Data on Bi2Se2Cl7 by Materials Project
Bi2Cl7(Se)2 crystallizes in the tetragonal P4/n space group. The structure is two-dimensional and consists of eight selenium molecules and one Bi2Cl7 sheet oriented in the (0, 0, 1) direction. In the Bi2Cl7 sheet, Bi+2.50+ is bonded in a 8-coordinate geometry to eight Cl1- atoms. There are a spread of Bi–Cl bond distances ranging from 2.63–3.37 Å. There are five inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Bi+2.50+ atom. In the second Cl1- site, Cl1- is bonded in a square co-planar geometry to four equivalent Bi+2.50+ atoms. In the third Cl1- site, Cl1- is bonded in a distorted tetrahedral geometry to four equivalent Bi+2.50+ atoms. In the fourth Cl1- site, Cl1- is bonded in a distorted water-like geometry to three equivalent Bi+2.50+ atoms. In the fifth Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent Bi+2.50+ atoms.