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1.
On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.  相似文献   

2.
The reaction of o-C6H4(AsMe2)2 with VCl4 in anhydrous CCl4 produces orange eight-coordinate [VCl4{o-C6H4(AsMe2)2}2], whilst in CH2Cl2 the product is the brown, six-coordinate [VCl4{o-C6H4(AsMe2)2}]. In dilute CH2Cl2 solution slow decomposition occurs to form the VIII complex [V2Cl6{o-C6H4(AsMe2)2}2]. Six-coordination is also found in [VCl4{MeC(CH2AsMe2)3}] and [VCl4{Et3As)2]. Hydrolysis of these complexes occurs readily to form vanadyl (VO2+) species, pure samples of which are obtained by reaction of [VOCl2(thf)2(H2O)] with the arsines to form green [VOCl2{o-C6H4(AsMe2)2}], [VOCl2{MeC(CH2AsMe2)3}(H2O)] and [VOCl2(Et3As)2]. Green [VOCl2(o-C6H4(PMe2)2}] is formed from [VOCl2(thf)2(H2O)] and the ligand. The [VOCl2{o-C6H4(PMe2)2}] decomposes in thf solution open to air to form the diphosphine dioxide complex [VO{o-C6H4(P(O)Me2)2}2(H2O)]Cl2, but in contrast, the products formed from similar treatment of [VCl4{o-C6H4(AsMe2)2}x] or [VOCl2{o-C6H4(AsMe2)2}] contain the novel arsenic(V) cation [o-C6H4(AsMe2Cl)(μ-O)(AsMe2)]+. X-ray crystal structures are reported for [V2Cl6{o-C6H4(AsMe2)2}2], [VO(H2O){o-C6H4(P(O)Me2)2}2]Cl2, [o-C6H4(AsMe2Cl)(μ-O)(AsMe2)]Cl·[VO(H2O)3Cl2] and powder neutron diffraction data for [VCl4{o-C6H4(AsMe2)2}2].  相似文献   

3.
The photochemical reaction of piperazine with C70 produces a mono‐adduct (N(CH2CH2)2NC70) in high yield (67 %) along with three bis‐adducts. These piperazine adducts can combine with various Lewis acids to form crystalline supramolecular aggregates suitable for X‐ray diffraction. The structure of the mono‐adduct was determined from examination of the adduct I2N(CH2CH2)2NI2C70 that was formed by reaction of N(CH2CH2)2NC70 with I2. Crystals of polymeric {Rh2(O2CCF3)4N(CH2CH2)2NC70}n?nC6H6 that formed from reaction of the mono‐adduct with Rh2(O2CCF3)4 contain a sinusoidal strand of alternating molecules of N(CH2CH2)2NC70 and Rh2(O2CCF3)4 connected through Rh?N bonds. Silver nitrate reacts with N(CH2CH2)2NC70 to form black crystals of {(Ag(NO3))4(N(CH2CH2)2NC70)4}n?7nCH2Cl2 that contain parallel, nearly linear chains of alternating (N(CH2CH2)2NC70 molecules and silver ions. Four of these {Ag(NO3)N(CH2CH2)2NC70}n chains adopt a structure that resembles a columnar micelle with the ionic silver nitrate portion in the center and the nearly non‐polar C70 cages encircling that core. Of the three bis‐adducts, one was definitively identified through crystallization in the presence of I2 as 12{N(CH2CH2)2N}2C70 with addends on opposite poles of the C70 cage and a structure with C2v symmetry. In 12{I2N(CH2CH2)2N}2C70, individual 12{I2N(CH2CH2)2N}2C70 units are further connected by secondary I2???N2 interactions to form chains that occur in layers within the crystal. Halogen bond formation between a Lewis base such as a tertiary amine and I2 is suggested as a method to produce ordered crystals with complex supramolecular structures from substances that are otherwise difficult to crystallize.  相似文献   

4.
Reactions of R4Sb2 (R = Me, Et) with (Me3SiCH2)3M (M = Ga, In) and Crystal Structures of [(Me3SiCH2)2InSbMe2]3 and [(Me3SiCH2)2GaOSbEt2]2 The reaction of (Me3SiCH2)3In with Me2SbSbMe2 gives [(Me3SiCH2)2InSbMe2]3 ( 1 ) and Me3SiCH2SbMe2. [(Me3SiCH2)2GaOSbEt2]2 ( 2 ) is formed by the reaction of (Me3SiCH2)3Ga with Et2SbSbEt2 and oxygen. The syntheses and the crystal structures of 1 and 2 are reported.  相似文献   

5.
Ten organotin derivatives with dithiocarbamates of the formulae (4‐NCC6H4CH2)2Sn(S2CNEt2)2 (1), (4‐NCC6H4CH2)2Sn(S2CNBz2)2 (2), (4‐NCC6H4CH2)2Sn[S2CN(CH2CH2)2NCH3]2 (3), (2‐ClC6H4CH2)2 Sn(S2CNEt2)2 (4), (2‐ClC6H4CH2)2Sn(S2CNBz2)2 (5), (4‐NCC6H4CH2)2Sn(Cl)S2CNEt2 (6), (4‐NCC6H4CH2)2Sn(Cl)S2CNBz2 (7), (4‐NCC6H4CH2)2Sn(Cl)S2CN(CH2CH2)2NCH3 (8), (2‐ClC6H4CH2)2 Sn(Cl)S2CNEt2 (9) and (2‐ClC6H4CH2)2Sn(Cl)S2CNBz2 (10) have been prepared. All complexes were characterized by elemental analyses, IR and NMR. The crystal structures of complexes 1 and 10 were determined by X‐ray single crystal diffraction. For complex 1, the central tin atom exists in a skew‐trapezoidal planar geometry defined by two asymmetrically coordinated dithiocarbamate ligands and two 4‐cyanobenzyl groups. In addition, because of the presence of close intermolecular non‐bonded contacts, complex 1 is a weakly‐bridged dimer. In complex 10, the central tin atom is rendered pentacoordinated in a distorted trigonal bipyramidal configuration by coordinating with S atoms derived from the dithiocarbamate ligand. In vitro assays for cytotoxicity against five human tumor cell lines (MCF‐7, EVSA‐T, WiDr, IGROV and M226) furnished the significant toxicities of the title complexes. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

6.
On the refluxing ofM(II) oxalate (M=Mn, Co, Ni, Cu, Zn or Cd) and 2-ethanolamine in chloroform, the following complexes were obtained: MnC2O4·HOCH2CH2NH2·H2O, CoC2O4·2HOCH2CH2NH2, Ni2(C2O4)2·5HOCH2CH2NH2·3H2O, Cu2(C2O4)2·5HOCH2CH2NH2, Zn2(C2O4)2·5HOCH2CH2NH2·2H2O and Cd2(C2O4)2·HOCH2CH2NH2·2H2O. Following the reaction ofM(II) oxalate with 2-ethanolamine in the presence of ethanolammonium oxalate, a compound with the empirical formula ZnC2O4·HOCH2CH2NH2·2H2O1 was isolated. The complexes were identified by using elemental analysis, X-ray powder diffraction patterns, IR spectra, and thermogravimetric and differential thermal analysis. The IR spectra and X-ray powder diffraction patterns showed that the complexes obtained were not isostructural. Their thermal decompositions, in the temperature interval between 20 and about 900°C, also take place in different ways, mainly through the formation of different amine complexes. The DTA curves exhibit a number of thermal effects.  相似文献   

7.
The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance.  相似文献   

8.
A cobalt‐containing monodentate phosphine [(μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)4][μ2‐η2‐PhC≡CP(i‐Pr)2] 2f , was prepared from the reaction of (μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)6 1 with PhC≡CP(i‐Pr)2. It was accompanied by an oxidized compound, [(μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)4][μ2‐η2‐PhC≡CP(=O)(i‐Pr2)] 2fo during the chromatographic process. Further reaction of 2f with Mo(CO)6 resulted in the formation of a 2f ‐ligated molybdenum complex 4 , [(μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)4][μ2‐η2‐PhC≡CP(i‐Pr2)‐κP]‐Mo(CO)5.  相似文献   

9.
The mass spectra of the following acetylenic derivatives of iron, ruthenium and osmium carbonyls are reported: the iron compounds Fe2(CO)6[C2(C6H5)s2]2, Fe2(CO)6[C2(CH3)2]2 and Fe2(CO)6[C2(C2H5)2]2, the ruthenium compounds Ru2(CO)6[C2(C6H5)2]2, and Ru2(CO)6[C2(CH3)2]2 and the osmium compounds Os2(CO)6[C2(C6H5)2]2, Os2(CO)6[C2HC6H5]2 and Os2(CO)6[C2(CH3)2]2. Iron compounds exhibit breakdown schemes where binuclear, mononuclear and hydrocarbon ions are present. On the other hand, ruthenium and osmium compounds fragment in a similar way and give rise to singly and doubly charged binuclear ions. Phenylic derivatives of ruthenium and osmium also give weak triply charged ions. The results are discussed in terms of relative strengths of the metal-metal and metal-carbon bonds.  相似文献   

10.
Hydrolysis reactions of di- and trinuclear organotin halides yielded large novel cage compounds containing Sn−O−Sn bridges. The molecular structures of two octanuclear tetraorganodistannoxanes showing double-ladder motifs, viz., [{Me3SiCH2(Cl)SnCH2YCH2Sn(OH)CH2SiMe3}2(μ-O)2]2 [ 1 , Y=p-(Me)2SiC6H4-C6H4Si(Me)2] and [{Me3SiCH2(I)SnCH2YCH2Sn(OH)CH2SiMe3}2(μ-O)2]2 ⋅ 0.48 I2 [ 2⋅ 0.48 I2, Y=p-(Me)2SiC6H4-C6H4Si(Me)2], and the hexanuclear cage-compound 1,3,6-C6H3(p-C6H4Si(Me)2CH2Sn(R)2OSn(R)2CH2Si(Me)2C6H4-p)3C6H3-1,3,6 ( 3 , R=CH2SiMe3) are reported. Of these, the co-crystal 2⋅ 0.48 I2 exhibits the largest spacing of 16.7 Å reported to date for distannoxane-based double ladders. DFT calculations for the hexanuclear cage and a related octanuclear congener accompany the experimental work.  相似文献   

11.
The complexes [Pd(Me2PO2)2]3 and Pd(Me2AsO2)2 were prepared from the corresponding acids and palladium(II) acetate. Their structures were deduced by IR and NMR spectroscopy. Addition of pyridine and 2,2′‐bipyridine to [Pd(Me2PO2)2]3 gave the adducts Pd(Me2PO2)2py2 and Pd(Me2PO2)2bipy, which were characterized by 1H NMR spectroscopy. Addition of nicotinic acid and nicotinamide in water gave the adducts Pd(Me2PO2)2L2, whereas in methanol the adducts Pd(Me2PO2)2L were obtained. The cacodylate containing complex formed the adducts Pd(Me2AsO2)2py and Pd(Me2AsO2)2bipy1/2, which are unstable in CDCl3. Triphenylphosphine deoxygenated both Pd(Me2MO2)2 complexes, but the palladium(II) containing products could not be isolated. The expected Pd(Me2P–O)2 reacted further and gave many products, whereas the anticipated Pd(Me2As–O)2 did not bind triphenylphosphine.  相似文献   

12.
The reaction of [Pt2(μ-S)2(P-P)2] (P-P=2PPh3, 2PMe2Ph, dppf) [dppf=1,1-bis(diphenylphosphino)ferrocene] with cis-[M(C6F5)2(PhCN)2] (M=Ni, Pd) or cis-[Pt(C6F5)2(THF)2] (THF=tetrahydrofuran) afforded sulfide aggregates of the type [{Pt23-S)2(P-P)2}M(C6F5)2] (M=Ni, Pd, Pt). X-ray crystal analysis revealed that [{Pt23-S)2(dppf)2}Pd(C6F5)2], [{Pt23-S)2(PPh3)2}Ni(C6F5)2], [{Pt23-S)2(PPh3)2}Pd(C6F5)2] and [{Pt23-S)2(PMe2Ph)2}Pt(C6F5)2] have triangular M3S2 core structures capped on both sides by μ3-sulfido ligands. The structural features of these polymetallic complexes are described. Some of them display short metal-metal contacts.  相似文献   

13.
The reaction of PtCl2L (L = diphosphine) with the appropriate diphosphine L′ in ethanol followed by reduction with aqueous sodium borohydride leads to either disproportionation to give mixtures of the bis(diphosphine) complexes PtL2 and PtL′2 or to the formation of the mixed ligand complex PtLL′ depending on the diphosphines. Mixed ligand complexes are obtained when L=Ph2P(CH2)2PPh2, L′ = Ph2P(CH2PPh2cis-Ph2PCH CHPPh2, Ph2P(CH2)2AsPh2, Ph2- P(CH2)4PPh2, o-Ph2PC6H4PPh2; and L=(C6H11)2P(CH22P(C6H11)2, L′= Ph2P(CH2)PPh2, Ph2P(CH2)2PPh2cis-Ph2PCHCHPPh2, (2S,3S)-Ph2PCH- (CH3)CH(CH3)PPh2, (R)-Ph2PCH(CH3)CH2PPh2. When L=Ph2P(CH2)4PPh2 L′= Ph2P(CH23PPh2 or cis-Ph2PCHCHRPh2 the mixed ligand complexes are obtained but extensive disproportionation also occurs.  相似文献   

14.
Treatment of Au2(Ph2PCH2CH2PPh2)Cl2 with one equivalent of the [Ru5C(CO)14]2− dianion in the presence of TlPF6 gives Ru5C(CO)14Au2(Ph2PCH2CH2PPh2) (1) in good yield and the [{Ru5C(CO)14}2Au2(Ph2PCH2CH2PPh2)]2− (2) anion in low yield. Complex 2 becomes the major product if 2 equivalents of [Ru5C(CO)14]2− are used. Reaction of [Au2(Ph2PCH2CH2PPh2)Cl2] with 3 equivalents of [H3Os4(CO)12] anion in the presence of TlPF6 affords {H3Os4(CO)12}2Au2(Ph2PCH2CH2PPh2) (3) in reasonable yield. X-ray diffraction studies of 1 and 3 show that they contain the [Au2(Ph2PCH2CH2PPh2)]2+ fragment in different coordination modes.  相似文献   

15.
Chloroselenates with Di- and Tetravalent Selenium: 77Se-NMR-Spectra, Syntheses, and Crystal Structures of (PPh4)2SeCl6 · 2 CH2Cl2, (NMe3Ph)2SeCl6, (K-18-crown-6)2SeCl6 · 2 CH3CN, PPh4Se2Cl9, (NEt4)2Se2Cl10, (PPh4)2Se3Cl8 · CH2Cl2, and (PPh4)2Se4Cl12 · CH2Cl2 The title compounds were obtained from reactions of selenium and selenium tetrachloride with PPh4Cl, NEt4Cl, NMe3PhCl, or (K-18-crown-6)Cl in dichloromethane or acetonitrile. (PPh4)2Se3Cl8 · CH2Cl2 was also formed from GeSe, PPh4Cl and chlorine in acetonitrile. The 77Se-NMR spectra of the solutions show the presence of dynamical equilibria which, depending on composition, mainly contain SeCl2, SeCl4, Se2Cl2, SeCl62–, Se2Cl62–, and/or Se2Cl102–. Solutions of AsCl3 and (PPh4)2Se4 in acetonitrile upon chlorination with Cl2 or PPh4AsCl6 yielded (PPh4)2Se2Cl6, while (PPh4)2As2Se4Cl12 was the product after chlorination with SOCl2. According to the X-ray crystal structure analyses the ions SeCl62–, Se2Cl9, and Se2Cl102– have the known structures with octahedral coordination of the Se atoms. The structure of the Se3Cl82– ion corresponds to that of Se3Br82– consisting of three SeCl2 molecules associated via two Cl ions. (PPh4)2Se4Cl12 · CH2Cl2 is isotypic with the corresponding bromoselenate and contains anions in which three SeCl2 molecules are attached to a SeCl62– ion; there is a peculiar Se–Se interaction.  相似文献   

16.
(NEt4)2[WIVO(S2C2(CN)2)2] (1), isolated by reaction of Na2 WO4, Na2S2C2(CN)2 (Na2mnt) in acidified (pH5.5) aqueous medium in the presence of excess of sodium dithionite and NEt4Br, reduces CO2/HCO 3 (pH 7.5) to yield HCOO and (NEt4)2[WVIO2(S2C2(CN)2)2] (2) mimicking tungsten-formate dehydrogenase (W-FDH) activity. (1) reacts with Na2MoO4 in acidic medium to produce [MoIvO(S2C2(CN)2)2]2− implicating the displacement of tungsten by molybdenum from the cofactor complex in W-FDH.  相似文献   

17.
Reactions of CrO2F2 with MF or MF2 gave the corresponding M2CrO2F4 and MCrO2F4 fluorochromates. With the Lewis Acids (SO3, TaF5, SbF5) and (CF3CO)2O known and new chromyl compounds [CrO2(CF3COO)2, CrO2(SO3F)2, CrO2FTaF6, CrO2FSbF6, CrO2FSb2F11] were produced. Chromyl fluoride and inorganic salts (CF3COONa and NaNO3) produced the following complexes - Na2CrO2F2(CF3COO)2 and Na2CrO2F2(NO3)2. Unusual solid products were obtained with CrO2F2 and NO, NO2, SO2.A new method of preparing CrO2F2 is also presented.  相似文献   

18.
Molybdenum(VI) and tungsten(VI) dioxodiazide, MO2(N3)2 (M=Mo, W), were prepared through fluoride–azide exchange reactions between MO2F2 and Me3SiN3 in SO2 solution. In acetonitrile solution, the fluoride–azide exchange resulted in the isolation of the adducts MO2(N3)2⋅2 CH3CN. The subsequent reaction of MO2(N3)2 with 2,2′‐bipyridine (bipy) gave the bipyridine adducts (bipy)MO2(N3)2. The hydrolysis of (bipy)MoO2(N3)2 resulted in the formation and isolation of [(bipy)MoO2N3]2O. The tetraazido anions [MO2(N3)4]2− were obtained by the reaction of MO2(N3)2 with two equivalents of ionic azide. Most molybdenum(VI) and tungsten(VI) dioxoazides were fully characterized by their vibrational spectra, impact, friction, and thermal sensitivity data and, in the case of (bipy)MoO2(N3)2, (bipy)WO2(N3)2, [PPh4]2[MoO2(N3)4], [PPh4]2[WO2(N3)4], and [(bipy)MoO2N3]2O by their X‐ray crystal structures.  相似文献   

19.
Organotin derivatives of dimethyldithioarsinic (dithocacodylic) acid have been obtained from the appropriate organotin chloride and the sodium salt of the latter. Tin(IV) chloride and NaS2AsMe2 · 2 H2O yielded only two products, namely Cl2Sn(S2AsMe2)2 and Sn (S2AsMe2)4, regardless of the reagent ratio. Spectroscopic characterization of the compounds (infrared and1H NMR) provides structural information suggesting that the dimethyldithioarsinato group behaves as monodentate (or anisobidentate) ligand in Me2Sn(S2AsMe2)2, Bu2Sn-(S2AsMe2)2 and Cy3Sn(S2AsMe2), as bidentate in Ph2Sn(S2AsMe2)2, Ph3Sn(S2AsMe2) and Cl2As(S2AsMe2)2, whereas Sn(S2AsMe2)4 contains both mono- and bidentate ligands, presumably in a six-coordinate structure.  相似文献   

20.
One-, two- and three-dimensional CN-bridged metal complex structures made up of building blocks such as linear [Ag(CN)2], square planar [Ni(CN)4]2– or tetrahedral [Cd(CN)4]2–, and of the complementary ligands such as ammonia, water, unidentate amine, bidentate a,w- diaminoalkane, etc., are reviewed with an emphasis on their behaviour as hosts to afford clathrate inclusion compounds with guest molecules and as self-assemblies to form supramolecular structures with or without guests. The historical background is explained for Prussian blue and Hofmann's benzene clathrate based on their single crystal structure determinations. The strategies the author and coworkers have been applying to develop varieties of clathrate inclusion compounds from the Hofmann-type are demonstrated with the features observed for the developed structures determined by single crystal X-ray diffraction methods.Abbreviations for Ligands and Guests mma NMeH2 - dma NMe2H - tma NMe3 - mea NH2(CH2)2OH - en NH2(CH2)2NH2 - pn NH2CHMeCH2NH2 - tn NH2(CH2)3NH2 - dabtn NH2(CH2)4NH2 - daptn NH2(CH2)5NH2 - dahxn NH2(CH2)6NH2 - dahpn NH2(CH2)7NH2 - daotn NH2(CH2)8NH2 - danon NH2(CH2)9NH2 - dadcn NH2(CH2)10NH2 - mtn NMeH(CH2)3NH2 - dmtn NMe2(CH2)3NH2 - detn NEt2(CH2)3NH2 - temtn NMe2(CH2)3NMe2 - dien NH2(CH2)2NH(CH2)2NH2 - pXdam p-C6H4(NH2CH2)2 - rnXdam m-C6H4(NH2CH2)2 - py C5H5N pyridine - ampy NH2C5H4N aminopyridine - Clpy CIC5H4N chloropyridine - Mepy MeC5H4N methylpyridine - dmpy Me2C5H3N dimethylpyridine - bpy NC5H4C5H4N bipyridine - quin C7H9N quinoline - iquin iso-C7H9N isoquinoline - qxln C8H6N2 quinoxaline - Pe C5H11-pentyl imH: C3N2H4 imidazole - pyrz N(CHCH)2N pyrazine - Mequin MeC7H8N methylquinoline - bppn C13H14N2 1,3-bis(4-pyridyl)propane - bpb C14H8N2 1,4-bis(4-pyridyl)butadiyne - N-Meim C3N2H3Me N-methylimidazole - 2-MeimH C3N2H3Me 2-methylimidazole - dmf HOCNMe2 dimethylformamide - hmta C6H12N4 hexamethylenetetramine - o-phen C12H8N2 1,10-phenanthroline - den HN(CH2CH2)2NH piperazine - morph HN(CH2CH2)2O morpholine - ten N(CH2CH2)3N 1,4-diazabicyclo[2.2.2]octane - ameden NH2(CH2)2N(CH2CH2)2NH N-(2-aminoethyl)piperazine Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.  相似文献   

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