Three hexafluoridoiridates(IV), Ca[IrF6]·2H2O, Sr[IrF6]·2H2O and Ba[IrF6]
摘要:
The structures of the hexafluoridoiridates(IV) of calcium, Ca[IrF6]center dot 2H(2)O [calcium hexafluoridoiridate(IV) dihydrate], strontium, Sr[IrF6]center dot 2H(2)O [strontium hexafluoridoiridate( IV) dihydrate], and barium, Ba[IrF6] [barium hexafluoridoiridate(IV)], have been determined by single-crystal X-ray analysis. The first two compounds are isomorphous. Their metal cations are eight-coordinated in a distorted square-antiprismatic coordination environment, and their anions are represented by an almost ideal octahedron. These two structures can be described as frameworks in which all atoms occupy general positions. Sr[RhF6] and Ba[ RhF6] have a different space group (R (3) over barm, from powder diffraction data) but similar cell dimensions. The structures are very close to that of Ba[IrF6]. The cation is in a cuboctahedral coordination. The metal atoms are located on special positions of (3) over bar symmetry, while the F atoms are in general positions.
在将各种铂金属混合物加热到400°C时,研究了它们的混合物(M = Ru,Os,Rh,Ir,Pd,Pt)与KBrF 4的反应。在所有情况下,分别观察到氧化态为+4或+ 5,K 2 M F 6或K M F 6的氟代氟化金属铂金的形成。测试所得产物在水中的稳定性。根据铂金属的不同,它们要么稳定,要么被还原为+4的氧化态,要么被水解为迄今无法识别的相。ķ 2 RUF 6,K 2 OSF 6,α-K 2 PDF 6,β-K通过单晶或粉末X射线衍射,拉曼光谱和IR光谱对2 PdF 6进行了结构重新研究,以前这些PdF 6以前的表征较差。前三种化合物在三角形中结晶为同型,后者在六方晶体体系中结晶。发现K 2 PdF 6的α→β相变是可重构的。量子化学计算被用来研究晶体结构。
Iridium is used as a hardening agent in several alloys and as a new-generation catalyst. Therefore, its recycling is a high-priority challenge. The reactions of various tetrafluorobromates MBrF4 (M = K, Rb, Cs) and M′(BrF4)2 (M′ = Ba) with Ir metal were investigated in order to transform the latter to an easily soluble form to facilitate the further recovery of the noble metal. The compositions of
Synthesis and characterization of [PW11O39Ir(H2O)]4−: successful incorporation of Ir into polyoxometalate framework and study of the substitutional lability at the Ir(iii) site
作者:Maxim N. Sokolov、Sergey A. Adonin、Dmitry A. Mainichev、Cristian Vicent、Nina F. Zakharchuk、Andrey M. Danilenko、Vladimir P. Fedin
DOI:10.1039/c1cc10912j
日期:——
The first Keggin-type heteropolyanion, [PW11O39Ir(H2O)]4â (1), was synthesized by hydrothermal reaction from two different polytungstate precursors and [IrF6]2â. It was isolated as (Bu4N)4[PW11O39Ir(H2O)] (1a), which was completely characterized by multinuclear 31P and 183W NMR, ESI-mass spectrometry and cyclic voltammetry. A rapid screening methodology to ascertain the intrinsic substitutional lability at the Ir site is also presented, based on ESI-MS.
LiRhF6, LiIrF6, Li2RhF6, and K2IrF6 were obtained again, but for the first time investigated by single crystal X-ray methods. Rubyred LiRhF6 and yellow LiIrF6 crystallize isostructural in the trigonal space group R(3) over bar - C-3i(2) (Nr.148) with the lattice parameters LiRhF6: a 502.018(7) pm, c = 1355.88(3) pm, Z = 3 and d(Rh-F) = 185.5(1) pm; LiIrF6: a = 506.148(4) pm, c = 1362.60(2) pm, Z = 3, d(Ir-F) = 187.5(3) pm (LiSbF6-Typ). Yellow Li2RhF6 14 crystallizes tetragonal in the space group P4(2)/mnm - D-4h(14) (Nr.136) with a = 463.880(8) pm, c = 905.57(2) pm, Z = 2 and d(Rh-F) = 190.3(4)-191.4(3) pm (Trirutil-Typ). Yellow K2IrF6 3 crystallizes trigonal in the space group P(3$) over bar m1 - D-3d(3) (Nr.164) with a = 578.88(7) pm, c = 465.06(5) pm, Z = 1 and d(Ir-F) 194.0(6) pm, isotypic with K2GeF6.