Materials Data on K3U2O6F7 by Materials Project

Dataset · Sat Jan 12 04:00:00 EST 2019

DOI:https://doi.org/10.17188/1710747· OSTI ID:1710747

K3U2O6F7 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded to two O and four F atoms to form distorted KO2F4 octahedra that share corners with four equivalent UO2F5 pentagonal bipyramids. There are one shorter (2.81 Å) and one longer (2.93 Å) K–O bond lengths. There are two shorter (2.58 Å) and two longer (2.69 Å) K–F bond lengths. In the second K site, K is bonded in a 7-coordinate geometry to three O and four F atoms. There are two shorter (2.79 Å) and one longer (2.93 Å) K–O bond lengths. There are two shorter (2.68 Å) and two longer (2.81 Å) K–F bond lengths. In the third K site, K is bonded in a distorted body-centered cubic geometry to four O and four F atoms. There are two shorter (2.94 Å) and two longer (3.09 Å) K–O bond lengths. There are two shorter (2.65 Å) and two longer (2.86 Å) K–F bond lengths. U is bonded to two O and five F atoms to form UO2F5 pentagonal bipyramids that share corners with two equivalent KO2F4 octahedra, a cornercorner with one UO2F5 pentagonal bipyramid, and an edgeedge with one UO2F5 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 58–61°. There is one shorter (1.81 Å) and one longer (1.83 Å) U–O bond length. There are a spread of U–F bond distances ranging from 2.22–2.38 Å. There are four inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two K atoms. In the second O site, O is bonded in a distorted single-bond geometry to one K and one U atom. In the third O site, O is bonded in a distorted single-bond geometry to one K and one U atom. In the fourth O site, O is bonded in a T-shaped geometry to three K atoms. There are four inequivalent F sites. In the first F site, F is bonded in a trigonal planar geometry to one K and two equivalent U atoms. In the second F site, F is bonded in a bent 150 degrees geometry to two equivalent U atoms. In the third F site, F is bonded in a trigonal planar geometry to two K and one U atom. In the fourth F site, F is bonded to three K and one U atom to form a mixture of distorted corner and edge-sharing FK3U tetrahedra.

• Research Organization: LBNL Materials Project; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Contributing Organization: The Materials Project; MIT; UC Berkeley; Duke; U Louvain
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1710747
• Report Number(s): mp-1212160
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
F-K-O-U
K3U2O6F7
crystal structure