Hydrothermal synthesis of (C6N2H14)2(UVI2UIVO4F12,), a mixed-valent one-dimensional uranium oxyfluoride

被引:61
作者
Allen, S
Barlow, S
Halasyamani, PS
Mosselmans, JFW
O'Hare, D
Walker, SM
Walton, RI
机构
[1] Univ Oxford, Inorgan Chem Lab, Oxford OX1 3QR, England
[2] SERC, Daresbury Lab, CLRC, Warrington WA4 4AD, Cheshire, England
关键词
D O I
10.1021/ic000193r
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
A new hybrid organic-inorganic mixed-valent uranium oxyfluoride, (C6N2H14)(2)(U3O4F12), UFO-17, has been synthesized under hydrothermal conditions using uranium dioxide as the uranium source, hydrofluoric acid as mineralizer, and 1,4-diazabicyclo[2.2.2]octane as template. The single-crystal X-ray structure was determined. Crystals of UFO-17 belonged to the orthorhombic space group Cmcm (no. 63), with a = 14.2660(15) Angstrom, b = 24.5130(10) Angstrom, c = 7.201(2) Angstrom, and Z = 4. The structure reveals parallel uranium-containing chains of two types: one type is composed of edge-sharing UO2F5 units; the other has a backbone of edge-sharing UF8 units, each sharing an edge with a pendant UO2F5 unit. Bond-valence calculations suggest the UF8 groups contain UN, while the UO2F5 groups contain U-VI. EXAFS data give results consistent with the single-crystal X-ray structure determination, while comparison of the uranium L-III-edge XANES of UFO-17 with that of related U-IV and U-VI compounds supports the oxidation-state assignment. Variable-temperature magnetic susceptibility measurements on UFO-17 and a range of related hybrid organic-inorganic uranium(IV) and uranium(VI) fluorides and oxyfluorides further support the formulation of UFO-17 as a mixed-valent U-IV/U-VI compound.
引用
收藏
页码:3791 / 3798
页数:8
相关论文
共 41 条
[1]  
AHRLAND S, 1975, CHEM ACTINIDES
[2]  
ALKER SM, 1999, UNPUB
[3]   Aminoguanidinium fluorozirconates:: Improved synthesis and thermal decomposition of CN4H8ZrF6, CN4H8ZrF6.1/2H2O, CN4H8ZrF6.H2O, (CN4H7)2ZrF6, and CN4H7ZrF5 [J].
Bauer, MR ;
Ross, CR ;
Nielson, RM ;
Abrahams, SC .
INORGANIC CHEMISTRY, 1999, 38 (05) :1028-1030
[4]   U(UO2)((PO4)2, A NEW MIXED-VALENCE URANIUM ORTHOPHOSPHATE - AB-INITIO STRUCTURE DETERMINATION FROM POWDER DIFFRACTION DATA AND OPTICAL AND X-RAY PHOTOELECTRO SPECTRA [J].
BENARD, P ;
LOUER, D ;
DACHEUX, N ;
BRANDEL, V ;
GENET, M .
CHEMISTRY OF MATERIALS, 1994, 6 (07) :1049-1058
[5]   ELECTRONIC-STRUCTURE OF ACTINIDE COMPOUNDS FROM LIII-EDGE X-RAY ABSORPTION [J].
BERTRAM, S ;
KAINDL, G ;
JOVE, J ;
PAGES, M ;
GAL, J .
PHYSICAL REVIEW LETTERS, 1989, 63 (24) :2680-2683
[6]  
BINSTED N, 1991, EXAFS DATA ANAL PROG
[7]   BOND-VALENCE PARAMETERS FOR SOLIDS [J].
BRESE, NE ;
OKEEFFE, M .
ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE, 1991, 47 :192-197
[8]  
Burns PC, 1997, CAN MINERAL, V35, P1551
[9]  
Cascarano G., 1993, J APPL CRYSTALLOGR, V26, P343
[10]  
Cheetham AK, 1999, ANGEW CHEM INT EDIT, V38, P3268, DOI 10.1002/(SICI)1521-3773(19991115)38:22<3268::AID-ANIE3268>3.0.CO