Materials Data on U3Ni2O9F16 by Materials Project
(U3Ni2(O3F8)2)2(O2)3 crystallizes in the orthorhombic Cmcm space group. The structure is two-dimensional and consists of four trioxidane molecules and two U3Ni2(O3F8)2 sheets oriented in the (0, 0, 1) direction. In each U3Ni2(O3F8)2 sheet, there are two inequivalent U sites. In the first U site, U is bonded in a 9-coordinate geometry to nine F atoms. There are a spread of U–F bond distances ranging from 2.12–2.35 Å. In the second U site, U is bonded in a 9-coordinate geometry to nine F atoms. There are a spread of U–F bond distances ranging from 2.11–2.40 Å. Ni is bonded in an octahedral geometry to three O and three F atoms. There is two shorter (1.89 Å) and one longer (1.90 Å) Ni–O bond length. All Ni–F bond lengths are 2.20 Å. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Ni atom. In the second O site, O is bonded in a single-bond geometry to one Ni atom. There are seven inequivalent F sites. In the first F site, F is bonded in a bent 120 degrees geometry to two U atoms. In the second F site, F is bonded in a bent 120 degrees geometry to two equivalent U atoms. In the third F site, F is bonded in a bent 150 degrees geometry to one U and one Ni atom. In the fourth F site, F is bonded in a bent 150 degrees geometry to one U and one Ni atom. In the fifth F site, F is bonded in a bent 120 degrees geometry to two U atoms. In the sixth F site, F is bonded in a bent 120 degrees geometry to two equivalent U atoms. In the seventh F site, F is bonded in a trigonal planar geometry to three U atoms.