Materials Data on K3UF7 by Materials Project

Dataset · Wed Apr 29 04:00:00 EDT 2020

DOI:https://doi.org/10.17188/1189796· OSTI ID:1189796

K3UF7 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six F1- atoms to form KF6 octahedra that share corners with six equivalent UF7 pentagonal bipyramids. All K–F bond lengths are 2.67 Å. In the second K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share corners with four equivalent UF7 pentagonal bipyramids and edges with two equivalent UF7 pentagonal bipyramids. There are four shorter (2.71 Å) and four longer (2.79 Å) K–F bond lengths. In the third K1+ site, K1+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of K–F bond distances ranging from 2.63–3.25 Å. U4+ is bonded to seven F1- atoms to form UF7 pentagonal bipyramids that share corners with two equivalent KF8 hexagonal bipyramids, corners with three equivalent KF6 octahedra, and an edgeedge with one KF8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 0–37°. There are a spread of U–F bond distances ranging from 2.18–2.30 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a 4-coordinate geometry to three K1+ and one U4+ atom. In the second F1- site, F1- is bonded in a 3-coordinate geometry to four K1+ and one U4+ atom. In the third F1- site, F1- is bonded in a 2-coordinate geometry to five K1+ and one U4+ atom. In the fourth F1- site, F1- is bonded to three K1+ and one U4+ atom to form a mixture of distorted edge and corner-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: 1189796
• Report Number(s): mp-13897
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
F-K-U
K3UF7
crystal structure