DOI: 10.17188/1744431
title: Materials Data on K12Sn4Au21 by Materials Project

description: K12Au21Sn4 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are six inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 12-coordinate geometry to two K1+ and ten Au1- atoms. There are one shorter (3.51 Å) and one longer (3.64 Å) K–K bond lengths. There are a spread of K–Au bond distances ranging from 3.41–3.99 Å. In the second K1+ site, K1+ is bonded in a 12-coordinate geometry to two equivalent K1+ and twelve Au1- atoms. There are a spread of K–Au bond distances ranging from 3.47–3.88 Å. In the third K1+ site, K1+ is bonded in a 1-coordinate geometry to one K1+ and ten Au1- atoms. The K–K bond length is 3.62 Å. There are a spread of K–Au bond distances ranging from 3.28–3.84 Å. In the fourth K1+ site, K1+ is bonded in a 3-coordinate geometry to ten Au1- atoms. There are a spread of K–Au bond distances ranging from 3.27–4.00 Å. In the fifth K1+ site, K1+ is bonded in a 8-coordinate geometry to two equivalent K1+ and eight Au1- atoms. There are four shorter (3.83 Å) and four longer (3.91 Å) K–Au bond lengths. In the sixth K1+ site, K1+ is bonded in a 12-coordinate geometry to twelve Au1- atoms. There are a spread of K–Au bond distances ranging from 3.60–3.73 Å. There are eight inequivalent Au1- sites. In the first Au1- site, Au1- is bonded to six K1+ and six Au1- atoms to form AuK6Au6 cuboctahedra that share corners with two equivalent AuK6Au6 cuboctahedra, a cornercorner with one SnAu4 trigonal pyramid, edges with two equivalent AuK6Au6 cuboctahedra, and a faceface with one AuK6Au6 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.85–3.09 Å. In the second Au1- site, Au1- is bonded in a 1-coordinate geometry to six K1+, three Au1-, and one Sn+2.25+ atom. There are a spread of Au–Au bond distances ranging from 2.83–2.85 Å. The Au–Sn bond length is 2.70 Å. In the third Au1- site, Au1- is bonded in a 12-coordinate geometry to six K1+ and six Au1- atoms. There are a spread of Au–Au bond distances ranging from 2.84–2.95 Å. In the fourth Au1- site, Au1- is bonded in a 4-coordinate geometry to four K1+ and four Sn+2.25+ atoms. There are two shorter (2.82 Å) and two longer (2.89 Å) Au–Sn bond lengths. In the fifth Au1- site, Au1- is bonded in a 10-coordinate geometry to six K1+, three Au1-, and one Sn+2.25+ atom. The Au–Sn bond length is 2.70 Å. In the sixth Au1- site, Au1- is bonded to six K1+ and six Au1- atoms to form AuK6Au6 cuboctahedra that share corners with two equivalent AuK6Au6 cuboctahedra, corners with two equivalent SnAu4 trigonal pyramids, and edges with four AuK6Au6 cuboctahedra. Both Au–Au bond lengths are 2.83 Å. In the seventh Au1- site, Au1- is bonded in a 10-coordinate geometry to six K1+, three Au1-, and one Sn+2.25+ atom. The Au–Au bond length is 2.80 Å. The Au–Sn bond length is 2.71 Å. In the eighth Au1- site, Au1- is bonded in a 1-coordinate geometry to six K1+, three Au1-, and one Sn+2.25+ atom. The Au–Sn bond length is 2.70 Å. There are two inequivalent Sn+2.25+ sites. In the first Sn+2.25+ site, Sn+2.25+ is bonded to four Au1- atoms to form distorted SnAu4 trigonal pyramids that share corners with three AuK6Au6 cuboctahedra and a cornercorner with one SnAu4 trigonal pyramid. In the second Sn+2.25+ site, Sn+2.25+ is bonded in a rectangular see-saw-like geometry to four Au1- atoms.