Materials Data on Cr2NiH20(NO7)2 by Materials Project
NiH2(CrNHO4)2(H2)4(H2O2)2(H2O)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight hydrogen molecules, two nickel dihydride molecules, four water molecules, eight water molecules, and four CrNHO4 clusters. In each CrNHO4 cluster, Cr6+ is bonded in a 3-coordinate geometry to one N3- and four O2- atoms. The Cr–N bond length is 1.86 Å. There are a spread of Cr–O bond distances ranging from 1.60–2.02 Å. N3- is bonded in a distorted L-shaped geometry to one Cr6+ and one O2- atom. The N–O bond length is 1.24 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Cr6+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Cr6+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Cr6+ and one N3- atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Cr6+ and one H1+ atom.