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1.
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   

2.
Summary Typical precipitation curves of various metal phosphates have been obtained using the turbidimetric technique. The following systems have been investigated: Al(NO3)3-K3PO4, Al(NO3)3-KH2PO4, Al(NO3)3NaH2PO4, FeCl3-K3PO4, FeCl3-(NH4)2HPO4, FeCl3K2HPO4, FeCl3-KH2PO4, FeCl3-NaH2PO4, La(NO3)3K3PO4,La(NO3)3-K2HPO4,La(NO3)3-KH2PO4,La(NO3)3NaH2PO4 and Th(NO3)4-K2HPO4. Typical precipitation curves indicated concentration ranges of phosphate precipitation and of complex solubility.
Zusammenfassung Typische F?llungskurven verschiedener Metallphosphate, die mittels Trübungsmessungen erhalten wurden, wurden graphisch dargestellt. Die folgenden Systeme wurden untersucht: Al(NO3)3-K3PO4,Al(NO3)3KH2PO4, Al(NO3)3-NaH2PO4, FeCl3-K3PO4, FeCl3(NH4)2HPO4, FeCl3-K2HPO4, FeCl3-KH2PO4, FeCl3NaH2PO4, La(NO3)3-K3PO4, La(NO3)3-K2HPO4, La(NO3)3-KH2PO4, La(NO3)3-NaH2PO4 und Th(NO3)4K2HPO4. Typische F?llungskurven zeigten Konzentrationsgebiete, in welchen die Metallphosphate gef?llt werden, sowie Konzentrationen, die zur Komplexbildung führten.

Supported in part by the U.S. Army Research Office, Contract No. DA-ORD-10.  相似文献   

3.
The tertiary phosphine π-C5H5Fe(CO)2P(C6H5)2 reacts with a suspension of Fe2(CO)9 in benzene to give the dinuclear complex π-C5H5Fe2P(C6H5)2(CO)6. This compound is also obtained by nucleophilic attack of [π-C5H5Fe(CO)2]− on Fe(CO)4-[P(C6H5)2Cl] in tetrahydrofuran. Irradiation of a benzene solution of π-C5H5Fe2-P(C6H5)2(CO)6 with ultraviolet light affords π-C5H5Fe2P(C6H5)2(CO)5 which contains both a bridging carbonyl and a bridging phosphido group. The unstable bridged sulphido derivatives π-C5H5Fe2SR(CO)6 (R = CH3 and C6H5) and π-C5H5Fe2(t-C4H9S)(CO)5 are similarly obtained employing π-C5H5Fe(CO)2SR as ligand. The reactions of π-C5H5Fe2P(C6H5)2(CO)5 with tertiary phosphines and phosphites yield three types of products depending on the reaction conditions and the ligand involved. Examples include π-C5H5Fe2P(C6H5)2(CO)4P(C6H5)3, a mono-substituted derivative of π-C5H5Fe2P(C6H5)2(CO)5, and π-C5H5Fe2P(C6H5)2(CO)5P(C2H5)3 and π-C5H5Fe2P(C6H5)2(CO)4[P(OCH)3)3]2, mono- and bis-substituted derivatives of π-C5H5Fe2P(C6H5)2(CO)6, respectively. The reaction of π-C5H5Fe2P(C6H52(CO)5 with (C6H5)2PCH2P(C6H5)2 in benzene under reflux affords [π-C5H5Fe2P(C6H5)2(CO)4](C6H5)2PCH2P(C6H5)2 in which the ditertiary phosphine bridges two iron atoms.  相似文献   

4.
The dinuclear cobalt complex [CH2(C5H4)2][Co(PMe3)2]2 (2), which is prepared from CoCl(PMe3)3 and [CH2(C5H4)2]Li2, reacts with NH4PF6 and CH3I to form the protonated and methylated dications {[CH2(C5H4)2][CoR(PMe3)2]2}2+ (R = H, CH3). Treatment of {[CH2(C5H4)2][CoCH3(PMe3)2]2}I2 (4) with LiCH3 affords the neutral compound [CH2(C5H4)2][Co(CH3)2(PMe3)]2 (5). Ligand substitution of [CH2(C5H4)2][Co(CO)2]2 (6) with P2Me4 and 1,2-C2H4(PMe2)2(dmpe) gives the doubly-bridged complexes [CH2(C5H4)2][Co2(CO)2(μ-P2Me4)] (7) and [CH2(C5H4)2][Co2(CO)2(μ-dmpe)] (8), respectively. Similarly, [CH2(C5H4)2][Co-(CO)(PMe3)]2 (9) is obtained from the reaction of 6 with PMe3. Oxidation of 6 with iodine gives [CH2(C5H4)2][Co(CO)I2]2 (11) which is transformed via {[CH2(C5H4)2][Co(PMe2H)3]2}I4 (12) into the triply-bridged cobalt(II) complex [CH2(C5H4)2][CO2(μ-PMe2)2] (13).  相似文献   

5.
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   

6.
The ditertiary phosphines (C6H5)2P(CH2)nP(C6H5)2 (n = 1 and 2), cis(C6H5)2PC2H2P(C6H5)2 and (C6H5)2PN(C2H5)P(C6H52 and the ditertiary arsines (C6H5)2As(CH2)nAs(C6H5)2 (n = 1 and 2) react with [Fe(CO)3SC6H5]2 to give a wide range of products, the nature of which depends on the reaction conditions and the ligand involved. Examples of the different types of comp isolated include, (i) Fe2(CO)5[(C6H5)2PCH2P(C6H5)2](SC6H5)2, in which the ligand acts as a monodentate, (ii) {[Fe(CO)2SC6H5]2[(C6H5)2PC2H4P(C6H5)2]}2, in which two [Fe(CO)2SC6H5]2 moieties are bridged by two diphosphine ligands, (iii) [Fe(CO)2SC6H5]2[(C6H5)2PN(C2H5)P(C6H5)2], in which the ligand bridges the two iron atoms, and (iv) Fe(CO)3(SC6H5)2Fe(CO)[(C6H5)2PC2H2P(C6H5)2], which contains the ligand chelated to a single iron atom. The tertiary phosphines PR3 (R=C2H5 and C6H5), phosphites P(OR′)3(R′ = CH3, C2H5, i-C3H7 and C6H5) and the stibine Sb(C6H5)3 bring about mono-, bis- or tris-substitution in [Fe(CO)3SC6H5]2 depending on the reaction conditions and the ligand involved. Whereas in solution [Fe(CO)2L(SC6H5)]2 [L = PR3 (R = C2H5 and C6H5), P(OC6H5)3 and Sb(C6H5)3] exist as a single isomer, [Fe(CO)2L′(SC6H5)]2 [L′=P(OR′)3 (R'=CH3, C2H5 and i-C3H7)] occur as a mixture of isomers.  相似文献   

7.
Diphenylphosphorylazide N3P(O)(OPh)2 reacts with Pt(PPh3)3, Pt(PPh3)2(C2H4), trans-RhCl(CO)(PPh3)2, Ru(CO)3(PPh3)2, CoCl2(PPh3)2 and CuCl(PPh3)2 to give the azido complexes Pt(PPh3)2(N3)R, Pt(PPh3)2(N3)2R2, the urylene complex RhCl(PPh3)2(RNCONR) and the phosphine imine complexes Ru(CO)3(RPPh3)2, CoCl2(RNPPh3)2, CuCl(RNPPh3)2, respectively, (RP(O)(OPh)2). The oxidative addition of n-C6F13SO2N3 to Pt(PPh3)4 and Pt(PPh3)2(C2H4) affords the complexes Pt(PPh3)2(N3)R and Pt(PPh3)2(N3)2R2, respectively, (RSO2C6F13. The compounds are characterized by elemental analysis and by their IR spectra.  相似文献   

8.
New Phosphido-bridged Multinuclear Complexes of Ag and Zn. The Crystal Structures of [Ag3(PPh2)3(PnBu2tBu)3], [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2, PnPr3), [Ag4(PPh2)4(PEt3)4]n, [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2, PnBu3, PEt2Ph), [Zn4(PhPSiMe3)4Cl4(C4H8O)2] and [Zn4(PtBu2)4Cl4] AgCl reacts with Ph2PSiMe3 in the presence of tertiary Phosphines (PnBu2tBu, PMenPr2, PnPr3 and PEt3) to form the multinuclear complexes [Ag3(PPh2)3(PnBu2tBu)3] 1 , [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2 2 , PnPr3 3 ) and [Ag4(PPh2)4(PEt3)4]n 4 . In analogy to that ZnCl2 reacts with Ph2PSiMe3 and PRR′2 to form the multinuclear complexes [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2 5 , PnBu3 6 , PEt2Ph 7 ). Further it was possible to obtain the compounds [Zn4(PhPSiMe3)4Cl4(C4H8O)2] 8 and [Zn4(PtBu2)4Cl4] 9 by reaction of ZnCl2 with PhP(SiMe3)2 and tBu2PSiMe3, respectively. The structures were characterized by X-ray single crystal structure analysis. Crystallographic data see “Inhaltsübersicht”.  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.
Adducts of cucurbit[6]uril with Ca2+ and trinuclear cluster chloroaquacomplexes (H9O4)2(H7O3)2[(Ca(H2O)5)2(C36H36N24O12)]Cl8·0.67H2O (1) and [(Ca(H2O)5)2(C36H36N24O12)]× [Mo3O2S2Cl6(H2O)3]2·13H2O (2) are obtained and structurally characterized. The structures of both compounds contain polymeric [Ca(H2O) n ]22 CB[6]∞ cations that form infinite columns; the space between them is filled with Cls- (1) and [Mo3O2S2Cl6(H2O)3]2s- (2). A new (H7O3)2(H5O2)× [Mo3S4Cl6.25Br0.25(H2O)2](C36H36N24O12)·CH2Cl2·6H2O complex (3) is also obtained and structurally characterized.  相似文献   

11.
The reaction of 1,1,1-tris(diiodarsinomethyl)ethane, CH3C(CH2AsI2)3 (I), with i-C3H7NH2, n-C4H9NH2, C6H5NH2, p-CH3C6H4NH2 and [(CH3)3Si]2NH in the presence of (C2H5)3N as auxiliary base in THF gives the adamantane cage compounds CH3C(CH2AsNC3H7)3 (III), CH3C(CH2AsNC4H9)3 (IV), CH3C(CH2AsNC6H5)3 (V), CH3C(CH2AsNC6H4CH3)3 (VI) and CH3C[CH2AsNSi(CH3)3]3 (VII). VII is also obtained in the reaction of I with NaN[Si(CH3)3]2. The by-product (CH3)3SiO(CH2)4I (VIII) could be isolated in both syntheses of VII. All compounds have been characterized by mass spectrometry and infrared, Raman and 1H NMR spectroscopy.  相似文献   

12.
Phase ratios in the three-component oxide system K2O-V2O4-SO3 in the region of the sulfur trioxide concentrations corresponding to its concentrations in the active component of vanadium catalysts for SO2 to SO3 conversion have been studied using powder X-ray diffraction, IR spectroscopy, microscopy, and chemical analysis. Four individual compounds (K2VO(SO4)2, K2(VO)2(SO4)3, K2VO(SO4)2S2O7, and K2(VO)2(SO4)2S2O7) and K2(VO)2(SO4)2S2O7 and VOSO4-base solid solutions of composition K2(VO)2+x (SO4)2+x S2O7 (0 ≤ x ≤ 1.5) were found in the system. K2VO(SO4)S2O7 and K2(VO)2(SO4)2S2O7 lose their sulfur trioxide when heated above 350°C under an inert atmosphere, and convert to K2VO(SO4)2 and K2(VO)2(SO4)3, respectively. This implies that K2VO(SO4)2S2O7 and K2(VO)2(SO4)2S2O7, as well as K2(VO)2+x (SO4)2+x S2O7 solid solution, cannot exist in the active component of real industrial catalysts.  相似文献   

13.
The triphenylsiloxy-substituted cyclotriphosphazenes, N3P3Cl5OSiPh3, gem-N3P3Cl4(OSiPh3)2, N3P3(OSiPh3)6, and N3P3(OPh)5OSiPh3, have been prepared. The synthesis of gem-N3P3Cl4(OSiPh3)2 involves the reaction of (NPCl2)3 with Ph3SiONa to form the intermediates gem-N3P3Cl4(OSiPh3)2(ONa) and gem-N3P3Cl4(ONa)2, which yield gem-N3P3Cl4(OSiPh3)2 when treated with Ph3SiCl. The compounds N3P3Cl5OSiPh3 and N3P3(OSiPh3)0 are formed by the condensation reactions of N3P3Cl5OBun and N3P3(OBun)6, respectively, with Ph3SiCl. The compound N3P3(OPh)5OSiPh3 is synthesized by the reaction between N3P3(OPh)5Cl and Et3SiONa to first give the intermediate N3P3(OPh)5ONa, which yields N3P3(OPh)5OSiPh3 when reacted with Ph3SiCl. The structural characterization and properties of these compounds are discussed. The crystal and molecular structure of gem-N3P3Cl4(OSiPh3)2 has been investigated by single-crystal X-ray diffraction techniques. The crystals are monoclinic with the space group P21/c with a = 16.850(8), b = 12.829(4), c = 18.505(15) Å, and β = 101.00(6)° with V = 3927 Å3 and Z = 4. © 1996 John Wiley & Sons, Inc.  相似文献   

14.
Variation of the reaction conditions with AgC??CR (R?=?Ph, t Bu), t BuPO3H2, (Et4N)VO3 and AgNO3 as starting materials afforded three isostructural globular neutral silver(I)-ethynide clusters incorporating the [( t BuPO3)4V4O8]4? unit as an integral shell component, namely {(NO3)2@Ag16(C??CPh)4[( t BuPO3)4V4O8]2(DEF)6(NO3)2}, {(NO3)2@Ag16(C??C t Bu)4[( t BuPO3)4V4O8]2(DMF)6(NO3)2}·DMF·2H2O and {(NO3)2@Ag16(C??C t Bu)4[( t BuPO3)4V4O8]2(DMF)6(NO3)2}·{(NO3)2@Ag16(C??C t Bu)4[( t BuPO3)4V4O8]2(DMF)4(py)2(NO3)2}·DMF·5H2O, in which the central cavity of each Ag16 cluster is occupied by two nitrate ions that function as a template. Furthermore, from the reaction of AgC??C t Bu with (NH4)4[V2O4(d,l-citrate)2]·4H2O, we isolated a new high-nuclearity silver(I)-ethynide cluster [(VO4)2@Ag34(C??C t Bu)22(NO3)6]·8H2O that encapsulates a pair of templating orthovanadate ions.  相似文献   

15.
Reactions of the Cycloheptatrienyl Complexes [η7-C7H7W(CO)3]BF4 and η7-C7H7Mo(CO)2Br with Neutral Ligands and the Electrochemical Reduction of the Wolfram Complex Compounds of the type [η7-C7H7M(CO)2L][BF4] (L = P(C6H5)3, As(C6H5)3, Sb(C6H5)3 for M = W and L = N2H4 for M = Mo) were synthesized and characterisized. The iodide η7-C7H7W(CO)2I reacts with the diphosphine ((C6H5)2PCH2)2 to give the trihapto complex η3-C7H7 W(CO)2I((C6H5)2PCH2)2. In the case of η7-C7H7Mo(CO)2 Br reaction with hydrazine leads to the substitution product [η7-C7H7 Mo(CO)2N2H4]⊕, which can be stabilized by large anions. The binuclear complex [C7H7W(CO)3]2 has been synthesized electrochemically.  相似文献   

16.
The Formation of Disilylphosphino-Element Compounds of C, Si, P The reactions of (me3Si)2PLi · OR2 a (OR2 = 1 monoglyme or 2 THF; me = CH3) with CH3Cl, CH2Cl2, ClCH2CH2Cl and ClCH2? C6H5 give the compounds (me3Si)2Pme, (me3Si)2P? CH2? P(Sime3)2, (me3Si)2P? CH2CH2Cl, (me3Si)2P? CH2CH2? P(Sime3)2 and (me3Si)2P? CH2C6H5 respectively. In the same manner a reacts with me2SiCl2 in a molar ratio 1:1 to (me3Si)2P? Sime2Cl and in a molar ratio 2:1 to (me3Si)2P? Sime2? P(Sime3)2 b . The compound b decomposes to [me3SiP? Sime2]2 and (me3Si)3P at 220°C. In the reactions of a with ClP(C6H5)2 and ClPme2 the compounds (me3Si)2P? P(C6H5)2 and (me3Si)2P? Pme2, respectively, are obtained. a reacts with HgCl2 to (me3Si)2P? P(Sime3)2. (me3Si)3P can be cleaved with ClP(C6H5)2 and ClPme2 yielding (me3Si)2P? P(C6H5)2 and (me3Si)2P? Pme2, respectively. The 1H- and 31P-n.m.r. and mass spectroscopic data are reported.  相似文献   

17.
The disproportionation reaction of diaryl ditellurides [(C6H5Te)2, (p-CH3C6H4Te)2, (p-CH3OC6H4Te)2, (p-C2H5OC4Te)2, (2-naphthyl-Te)2] with sodium hydroxide under phase transfer conditions at room temperature is described for the first time. The phase transfer catalyst used is 2HT-75, a trade name for a mixture of dialkyldimethylammonium chlorides. The intermediates aryl tellurolates react “in situ” with alkyl halides to give the corresponding alkyl aryl tellurides (ArTeR) in 52–72% yield. The following compounds were prepared: Ar  C6H5, R=CH3(CH2)3CH2, (CH3)2CHCH2CH2, (CH3)2CHCH2, CH3CHBrCH2CH2, CH3(CH2)8CH2, C6H5CH2, ClCH2, C6H5CH2CH2, CH2CHCH2, C6H5CHCHCH2, C6H5SeCH2, CH2CH2CH2CHCHCH; Ar=p-CH3C6H4, R = CH3(CH2)2CH2; Ar=p-CH3OC6H4, R = CH3(CH2)2CH2; Ar = p-CH2H5OC6H4, R= CH3(CH2)2CH2; Ar = 2-naphthyl, R = CH3(CH42)2CH2.  相似文献   

18.
Seven new mixed oxochalcogenate compounds in the systems MII/XVI/TeIV/O/(H), (MII = Ca, Cd, Sr; XVI = S, Se) were obtained under hydrothermal conditions (210 °C, one week). Crystal structure determinations based on single‐crystal X‐ray diffraction data revealed the compositions Ca3(SeO4)(TeO3)2, Ca3(SeO4)(Te3O8), Cd3(SeO4)(Te3O8), Cd3(H2O)(SO4)(Te3O8), Cd4(SO4)(TeO3)3, Cd5(SO4)2(TeO3)2(OH)2, and Sr3(H2O)2(SeO4)(TeO3)2 for these phases. Peculiar features of the crystal structures of Ca3(SeO4)(TeO3)2, Ca3(SeO4)(Te3O8), Cd3(SeO4)(Te3O8), Cd3(H2O)(SO4)(Te3O8), and Sr3(H2O)2(SeO4)(TeO3)2 are metal‐oxotellurate(IV) layers connected by bridging XO4 tetrahedra and/or by hydrogen‐bonding interactions involving hydroxyl or water groups, whereas Cd4(SO4)(TeO3)3 and Cd5(SO4)2(TeO3)2(OH)2 crystallize as framework structures. Common to all crystal structures is the stereoactivity of the TeIV electron lone pair for each oxotellurate(IV) unit, pointing either into the inter‐layer space, or into channels and cavities in the crystal structures.  相似文献   

19.
Phase relations have been established in the ternary system Ce-Rh-Si for the isothermal section at 800 °C based on X-ray powder diffraction and EPMA on about 80 alloys, which were prepared by arc melting under argon or by powder reaction sintering. From the 25 ternary compounds observed at 800 °C 13 phases have been reported earlier. Based on XPD Rietveld refinements the crystal structures for 9 new ternary phases were assigned to known structure types. Structural chemistry of these compounds follows the characteristics already outlined for their prototype structures: τ7—Ce3RhSi3, (Ba3Al2Ge2-type), τ8—Ce2Rh3−xSi3+x (Ce2Rh1.35Ge4.65-type), τ10—Ce3Rh4−xSi4+x (U3Ni4Si4-type), τ11—CeRh6Si4 (LiCo6P4-type), τ13—Ce6Rh30Si19.3 (U6Co30Si19-type), τ18—Ce4Rh4Si3 (Sm4Pd4Si3-type), τ21—CeRh2Si (CeIr2Si-type), τ22—Ce2Rh3+xSi1−x (Y2Rh3Ge-type) and τ24—Ce8(Rh1−xSix)24Si (Ce8Pd24Sb-type). For τ25—Ce4(Rh1−xSix)12Si a novel bcc structure was proposed from Rietveld analysis. Detailed crystal structure data were derived for τ3—CeRhSi2 (CeNiSi2-type) and τ6—Ce2Rh3Si5 (U2Co3Si5-type) by X-ray single crystal experiments, confirming the structure types. The crystal structures of τ4—Ce22Rh22Si56, τ5—Ce20Rh27Si53 and τ23—Ce33.3Rh58.2−55.2Si8.5−11.5 are unknown. High temperature compounds with compositions Ce10Rh51Si33 (U10Co51Si33-type) and CeRhSi (LaIrSi-type) have been observed in as-cast alloys but these phases do not participate in the phase equilibria at 800 °C.  相似文献   

20.
The positive-ion mass spectra of the following organonitrogen derivatives of metal carbonyls are discussed: (i) The compounds NC5H4CH2Fe(CO)2C5H5, NC5H4CH2COMo(CO)2C5H5, NC5H4CH2W(CO)3C5H5, NC5H4CH2COMn(CO)4, C5H10NCH2CH2Fe(CO)2C5H5, (CH3)2NCH2CH2COFeCOC5H5 and (CH3)2NCH2CH2COMn(CO)4 obtained from metal carbonyl anions and haloalkylamines, (ii) The isocyanate derivative C5H5Mo(CO)3CH2NCO; (iii) The arylazomolybdenum derivatives RN2Mo(CO)2C5H5 (R ? phenyl, p-tolyl, or p-anisyl); (iv) The compound (C6H5N)2COFe2(CO)6 obtained from Fe3(CO)12 and phenyl isocyanate; (v) The N,N,N′,N′-tetramethylethylenediamine complex (CH3)2NCH2CH2N(CH3)2W(CO)4. Further examples of eliminations of hydrogen, CO, and C2H2 fragments were noted. In addition evidence for the following more unusual processes was obtained: (i) Elimination of HCN fragments from the ions [NC5H4CH2MC5H5]+ to give the ions [(C5H5)2M]+ (M ? Fe, Mo and W); (ii) Conversion of C5H5Mo(CO)3CH2NCO to C5H5Mo(CO)2CH2NCO within the mass spectrometer; (iii) Elimination of N2 from [RN2MoC5H5]+ to give [RMoC5H5]+; (iv) Novel eliminations of HNCO, FeNCO, and C6H5NC fragments in the mass spectrum of (C6H5N)2COFe2(CO)6; (v) Facile dehydrogenation of the N,N,N′,-N′-tetramethylethylenediamine ligand in the complex (CH3)2NCH2CH2N(CH3)2W(CO)4.  相似文献   

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