Materials Data on U2Nb3Si4 by Materials Project

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

DOI:https://doi.org/10.17188/1723617· OSTI ID:1723617

U2Nb3Si4 crystallizes in the tetragonal P4_12_12 space group. The structure is three-dimensional. U+3.50+ is bonded to seven Si4- atoms to form distorted USi7 pentagonal bipyramids that share corners with four equivalent NbSi6 octahedra, corners with six equivalent USi7 pentagonal bipyramids, corners with five equivalent NbSi6 pentagonal pyramids, edges with three equivalent USi7 pentagonal bipyramids, edges with two equivalent NbSi6 pentagonal pyramids, faces with two equivalent NbSi6 octahedra, faces with two equivalent USi7 pentagonal bipyramids, and faces with four equivalent NbSi6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of U–Si bond distances ranging from 2.83–3.05 Å. There are two inequivalent Nb3+ sites. In the first Nb3+ site, Nb3+ is bonded to six Si4- atoms to form NbSi6 octahedra that share corners with four equivalent NbSi6 octahedra, corners with eight equivalent USi7 pentagonal bipyramids, corners with six equivalent NbSi6 pentagonal pyramids, faces with four equivalent USi7 pentagonal bipyramids, and faces with four equivalent NbSi6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 52°. There are a spread of Nb–Si bond distances ranging from 2.72–2.80 Å. In the second Nb3+ site, Nb3+ is bonded to six Si4- atoms to form distorted NbSi6 pentagonal pyramids that share corners with three equivalent NbSi6 octahedra, corners with five equivalent USi7 pentagonal bipyramids, corners with four equivalent NbSi6 pentagonal pyramids, edges with two equivalent USi7 pentagonal bipyramids, edges with four equivalent NbSi6 pentagonal pyramids, faces with two equivalent NbSi6 octahedra, and faces with four equivalent USi7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–43°. There are a spread of Nb–Si bond distances ranging from 2.61–2.69 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to three equivalent U+3.50+, five Nb3+, and one Si4- atom. The Si–Si bond length is 2.52 Å. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent U+3.50+, four Nb3+, and one Si4- atom.

• 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: 1723617
• Report Number(s): mp-1208053
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Nb-Si-U
U2Nb3Si4
crystal structure