Materials Data on K2CaCu(NO2)6 by Materials Project
K2Ca(NO2)6Cu crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional and consists of four copper molecules and one K2Ca(NO2)6 framework. In the K2Ca(NO2)6 framework, K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share edges with six equivalent KO12 cuboctahedra and faces with four equivalent CaO12 cuboctahedra. There are a spread of K–O bond distances ranging from 3.04–3.14 Å. Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share faces with eight equivalent KO12 cuboctahedra. There are four shorter (2.62 Å) and eight longer (2.71 Å) Ca–O bond lengths. There are three inequivalent N3+ sites. In the first N3+ site, N3+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both N–O bond lengths are 1.26 Å. In the second N3+ site, N3+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both N–O bond lengths are 1.27 Å. In the third N3+ site, N3+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both N–O bond lengths are 1.26 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+, one Ca2+, and one N3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+, one Ca2+, and one N3+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+, one Ca2+, and one N3+ atom.