Materials Data on UN2O7 by Materials Project
UN2O7 crystallizes in the orthorhombic Pbcn space group. The structure is one-dimensional and consists of two UN2O7 ribbons oriented in the (2, 0, -1) direction. U6+ is bonded in a distorted linear geometry to four O2- atoms. There are two shorter (1.79 Å) and two longer (2.51 Å) U–O bond lengths. N4+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both N–O bond lengths are 1.25 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent O2- atoms. Both O–O bond lengths are 2.96 Å. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one U6+, one N4+, and one O2- atom. In the third O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N4+ atom.