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1.
Preparation and Spectroscopic Characterization of the Pure Bondisomers [OsCl5(NCS)]2? and [OsCl5(SCN)]2? The oxidation of [OsCl5I]2? with (SCN)2 in CH2Cl2 yields the bondisomers [OsCl5(NCS)]2? and [OsCl5(SCN)]2?, which are isolated as pure compounds by ion exchange chromatography on DEAE-Cellulose. Only the salts of the N-isomer show significant shifts in the vibrational and electronic spectra caused by polarization of the terminal S depending on the size of the cations and the polarity of the solvents. In the IR and Raman spectra νCN(S), νCS(N) and δNCS are found at higher wave numbers than νCN(N), νCS(S) and δSCN. In the optical spectrum of the red [OsCl5(SCN)]2? the charge-transfer S→Os is nearly constant at 538 nm, but the N→Os transition of the yellow to violet coloured N-isomer shifts from 480 nm in organic solvents or in presence of large alkylammonium cations to 516 nm in aqueous solution and to 544 nm in the solid Cs-salt. The optical electronegativities are calculated to χopt(–SCN) = 2.6 and χopt(–NCS) = 2.6–2.8. According to spinorbit coupling and to lowered symmetry (C4v) the splitted intraconfigurational transitions are observed at 10 K as weak peaks in the regions 600, 1000 and 2000 nm. The O? O transitions are calculated from the vibrational fine structure. The lowest level of both isomers is confirmed by peaks in the electronic raman spectra. With the parameters ζ(OsIV) = 3200 cm?1 and B(? SCN) = 316 cm?1 or B(? NCS) = 288 cm?1 there is a good fit of calculated and experimental data, resulting in the nephelauxetic series: F? > CI? > SCN? > Br? > NCS? > I?.  相似文献   

2.
Preparation of trans-[Pt(N3)4X2]2? (X ? Br, I, SCN, SeCN) by Oxidative Addition to [Pt(N3)4]2? in Organic Solvents By oxidative addition to (TBA)2[Pt(N3)4], dissolved in dichlormethane, trans-(TBA)2[Pt(N3)4X2], X ? Br, I, SCN, SeCN; TBA = Tetrabutylammonium, are formed. The vibrational spectra of these salts are assigned according to point group D4h. From the resonance Raman spectrum of trans-(TBA)2[Pt(N3)4I2] the harmonic vibrational frequency ω1 of v(Pt? I), A1g, is calculated to be 138.50 cm?1 and the inharmonicity constant x11 = 0.27 cm?1. The characteristical feature in the UV/VIS spectra is caused by intensive π(N,X) → a1g, b1g(Pt) CT transitions.  相似文献   

3.
Preparation and Vibrational Spectra of Nonahalogenodirhodates(III), [Rh2ClnBr9-n]3?, n = 0–9 The pure nonahalogenodirhodates(III), A3[Rh2ClnBr9-n], A = K, Cs, (TBA); n = 0–4, 9, have been prepared. They are formed from the monomer chlorobromorhodates(III), [RhClnBr6-n]3?, n = 0–6, which are bridged to confacial bioctahedral complexes by ligand abstraction in less polar organic solvents. From the mixtures the complexions are separated by ion exchange chromatography on DEAE-cellulose. The solid, air-stable, air-stable, K-, Cs- and (TBA)-salts of [Rh2ClnBr9-n]3?, n = 0–4, are green, of [Rh2Cl9]3? are brown. The IR and Raman spectra of [Rh2Br9]3? and [Rh2Cl9]3? are assigned according to the point group D3h. The chlorobromodirhodates exist as mixtures of geometrical and structural isomers, which belong to different point groups. The vibrational spectra exhibit bands in characteristic regions; at high wavenumbers stretching vibrations with terminal ligands v(Rh—Clt): 360–320, v(Rh—Brt): 280–250; in a middle region with bridging ligands v(Rh—Clb): 300–270, v(Rh—Brb): 210–170 cm?1; the deformation bands are observed at distinct lower frequencies. The terminal ligands are fixed very strong, and the distance between v(Rh—Xt) and v(Rh—Xb) increases with decreasing size of the cations.  相似文献   

4.
Preparation, Vibrational Spectra, and Normal Coordinate Analysis of Hexachlororhenate(V) and Crystal Structure of [P(C6H5)4][ReCl6] By oxidation of A2[ReCl6], A = [(n-C4H9)4N]+, [P(C6H5)4]+, with Cl2 in dichloromethane/trifluoracetic acid A[ReCl6] is formed. [P(C6H5)4][ReCl6] crystallizes with tetragonal symmetry, space group P4/n-C, a = 12.967(4), c = 7.6992(8) Å, Z = 2. The octahedral complexion [ReCl6]? is compressed (C4v) with the bond lengths, axial Re? Cl1 = 2.28 and Re? Cl3 = 2.24 Å, equatorial Re? Cl2 = 2.31 Å. The infrared active antisymmetric Re? Cl stretching vibration is split into v3 = 346 an v3 = 326 cm?1. The assignment of all IR and Raman modes is confirmed by a normal coordinate analysis. The different valence force constants, fd(ReCl1) = 2.09, fd(ReCl3) = 2.10, fd(ReCl2) = 1.88 mdyn/ Å result from the distortion of the octahedron. On excitation with the Ar laser line 514.5 nm a resonance Raman spectrum is observed, showing 8 overtones of v′(A1) = 382 cm?1, from which the harmonic frequency ω1 = 382.1 cm?1, the anharmonicity constant X11 = ?0.76 cm?1, and the maximum bond dissociation energy of the [ReCl6]? ion to be 138 kcal/mol, are calculated. The vibrational fine structure of the intraconfigurational transitions in the near infrared has been resolved by measuring the absorption spectrum of [(n-C4H9)4N][ReCl6] at low temperature (10 K), resulting in the assignment of the following electronic origins: Γ3(3T1g) → Γ4(3T1g): 7 512, Γ3(3T1g) → Γ1(3T1g): 7 624 and Γ3(3T1g) → Γ5(1T2g), Γ3(1Eg): 8 368 cm?1.  相似文献   

5.
Pseudochalkogen Compounds. XVI. Infrared-spectroscopic Investigations of Cyanamidomonophosphates, [PO4?n(NCN)n]3? Infrared spectroscopic investigations of trisodium cyanamidomonophosphates of the general type Na3[PO4?n(NCN)n] · aq (n: 1, 2, 3) are reported. The vibrational spectra of the compounds are confirming very clearly the special position of cyanamidophosphates within the group of substituted phosphates: Cyanamidophosphates are characterized by a full participation of pseudochalkogen groups representing NCN substituents into the mesomeric system of the anions and an only slight shortening of the P? O distances in comparision to [PO4]3?. Characteristic frequencies between 970 and 1150 cm?1 are attributed to v(PO4?nNn)-stretching frequencies. A partial 15N labelling of the monocyanamidophosphate anion, [PO3NCN]3? leads to some splitting or shifting of frequencies being connected with vibrations of the NCN group; isolated v(P? N) stretching frequencies cannot be found.  相似文献   

6.
Preparation and vibrational spectra of the complexes [MBr6]?, [Br5MN3]? and [Br5MNPPh3]? of niobium and tantalum. Cyrstal structure of PPh4[NbBr6] The compounds PPh4[MBr6] and PPh4[MBr5N3] are obtained by reaction of MBr5 with PPh4Br or PPh4N3, respectively, in CH2Cl2 solution (M ? Nb, Ta). The azido complexes PPh4[MBr5N3] can also be obtained by reactions of the hexabromo complexes with iodine azide. According to its i.r. spectrum the symmetry of the [MBr6]? ion is lower than Oh in the solide state. This is corfirmed for PPh4[NbBr6] by a crystal structure analysis; it crystallizes in the monoclinic space group B2/b with four formula units in the unit cell and with the lattice constants a = 2301, b = 1777, c = 686 pm and γ = 96,6°. The structure was determined with X-ray diffraction data and was refined to a residual index of R = 0.055. The [NbBr6]? ion has the symmetry Ci, the deviations from Oh being small. In the azido complexes [MBr5N3]? the azido groups are covalently linked with the metal. From [NbBr5N3]? and PPh3 the complex [Br5Nb?N?PPh3]?, is obtained; for the analogous formation of the corresponding Ta complex photochemical activation is necessary. In this way the complex [Cl5Nb?N?AsPh3]? can also be obtained. I.r. spectra of all the compounds are reported and assigned.  相似文献   

7.
Preparation, Mössbauer and Vibrational Spectra of the Complexes [SnCl4F]?, [SnCl4(NCS)]?, and [SnCl4(NCS)2]2? N(CH2)4F and N(CH2)4SCN react in liquid SO2 with SnCl4 yielding the adducts [N(CH3)4][SnCl4F] (I), [N(CH3)4][SnCl4(NCS)] (II) and [N(CH3)4]2[SnCl4(NCS)2] (III).respectively. Mössbauer and vibrational spectra indicate for the anion of I a fluoro-bridged species, which is probably tetrameric like the isoelectronic SbCl4F. For II dimeric moieties are proposed with bridging S-atoms, while [SnCl4(NCS)2]2? has an octahedral structure with N-bonded isothiocyanate groups in the trans-positions.  相似文献   

8.
Preparation and spectroscopic characterization of the decahalogenodirhenates(IV), [Re2X10]2?, X = Cl, Br On heating of [ReX6]2? with trifluoroacetic acid/trifluoroacetic anhydride (1 : 1), the edge-sharing bioctahedral anions [Re2X10]2?, X = Cl, Br are formed, which IR and Raman spectra are assigned according to point group D2h. The bands are found in three characteristic regions; at high wavenumbers stretching vibrations with terminal ligands v(ReClt): 367–321, v(ReBrt): 242–195; in an intermediate region with bridging ligands v(ReClb): 278–250, v(ReBrb): 201–167 cm?1, and at distinct lower frequencies the deformation modes. The absorption spectra of the dirhenates are distinguished in the region 600–1400 nm by eight intraconfigurational transitions with a slight bathochromic shift and higher intensities in comparison to the monomeric complexes. Due to a stronger bonding of the terminal ligands the energy of the charge transfer bands is lowered by about 4 000 cm?1, too. The magnetic moments are 3.32 and 3.81 B.M./ReIV for [Re2Cl10]2? and [Re2Br10]2?, respectively.  相似文献   

9.
(PPh4)[(ReO2S2)CuI] and (NEt4)2[ReOS3)Cu3Cl4]: Fixation of the up to now not Isolated Ions [ReO2S2]? and [ReOS3]? Utilizing the Stability of the CuS2(Re) and Cu3S3(Re) Fragments (PPh4)[(ReO2S2)CuI] ( 1 ) and (NEt4)2[ReOS3)Cu3Cl4] ( 2 ) containing the up to now not isolated oxothioperrhenate ions [ReO2S2]? and [ReOS3]? as ligands, have been prepared by the reaction of (NEt4)[ReS4] with PPh3 and CuI in acetone in the presence of (PPh4)I (( 1 )) or with CuCl in CH2Cl2 in the presence of (NEt4)Cl (( 2 )), respectively. 1 and 2 have been characterized by X-ray structure analysis, elemental analysis and spectroscopic studies (IR, UV/Vis). The electronic spectra show bands which can approximately be assigned to interesting low-energy charge-transfer-transitions of the type d(Cu) → d(Re). For crystal data see Inhaltsübersicht.  相似文献   

10.
Vibrational and Electronic Spectra of Decahalogenodiosmates(IV), [Os2X10]2?, X ? Cl, Br The IR and Raman spectra of the edge-sharing bioctahedral anions [Os2X10]2?, X ? Cl, Br, are assigned according to point group D2h. The bands are found in three characteristic regions; at high wavenumbers stretching vibrations with terminal ligands v(OsClt): 365–280, v(OsBrt): 235–195; in a middle region with bridging ligands v(OsClb): 270–240, v(OsBrb): 175–165 cm?1; the deformation bands are observed at distinct lower frequencies. The electronic spectra of the dimers show intraconfigurational transitions near 2000, 1000, and 600 nm which by position and intensity correspond to those of the monomeric complexes. They are therefore discussed separately for both metal centers according to C2v symmetry. Two additional band systems are presumable pair transitions arising from interactions of the central ions within the dimeric complexes. Due to the different bonding strength of terminal or bridging ligands the intensive charge transfer bands are shifted by 3000–4000 cm?1 bathochromicly or by 2000–3000 cm?1 hypsochromicly compared with the hexahaloosmates(IV).  相似文献   

11.
The binary germanides M12Ge17 and M4Ge9 (M ? Na, K, Rb, Cs) and the stannides M12Sn17 and M4Sn9 (M ? K, Rb, Cs) were identified by a combination of direct synthesis, thermogravimetric analysis, vibrational spectroscopy, X-ray powder data and single crystal structure analysis. The M12E17 phases contain the cluster anions [E9]4? and [E4]4? in the ratio 1:2, forming a hierarchical structure with the cluster anions at the atomic positions of the hexagonal Laves phase MgZn2. Like the M4E4 phases, the M4Ge9 compounds are hierarchical derivatives of the cubic Cr3Si structure but with [Ge9]4? anions. The thermogravimetric analyses give strong evidence for the existence of at least one more phase with [E9]4? and [E4]4? clusters and of the clathrate phases M6E136 in addition to the well-known M8E442 chlathrates.  相似文献   

12.
Preparation and Spectroscopic Characterization of the Monofluorohydro-closo-borates [B6H5F]2? and [B12H11F]2? By treatment of [B6H6]2? with 1-(chloromethyl)-4-fluoro-1,4-diazabicyclo[2.2.2]octane-bis(tetrafluoroborate)in acetonitrile monofluorohydro-closo-hexaborate [B6H5F]2? ( 1 ) is formed in good yields. [B12H12]2? reacts with unhydrous HF yielding the monofluorododecaborate [B12H11F]2? ( 2 ). These compounds are separated by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose from by-products. The 11B nmr spectra exhibit the characteristic patterns (1 : 4 : 1) of a monosubstituted B6 octahedron and (1 : 5 : 5 : 1) of a monosubstituted B12 icosahedron with strong downfield shifts of the ipso-B nuclei at +9.3 ppm ( 1 ) and at +9.0 ppm ( 2 ). The 19F nmr spectra reveal quartets at ?212 ppm ( 1 ) and ?209 ppm ( 2 ) proving a B? F bonding. In the i.r. spectra, for ( 1 ) in the Raman spectrum too, cage vibrations depending on the F substituent at 1195 ( 1 ) and at 1182/1154 cm?1 ( 2 ) are observed. The Raman spectra show the B6F stretching mode at 535 cm?1 and the B12F stretching vibration at 445 cm?1.  相似文献   

13.
Oxidative addition of diphenyl disulfide to the coordinatively unsaturated [Mn(CO)5]? led to the formation of low-spin, six-coordinate cis-[Mn(CO)4(SPh)2]?. The complex cis-[PPN][Mn(CO)4(SPh)2] crystallized in monoclinic space group P21/c with a = 9.965(2) Å, b = 24.604(5) Å, c = 19.291(4) Å, β = 100.05(2)°, V = 4657(2)Å3, and Z = 4; final R = 0.036 and Rw = 0.039. Thermal transformation of cis-[Mn(CO)4(SPh)2]? to [(CO)3Mn(μ-SPh)3Mn(CO)3]? was completed overnight in THF at room temperature. Additionally, reaction of [Mn(CO)5]? and PhSH in 1:2 mole ratio also led to cis-[PPN](Mn(CO)4(SPh)2]. Presumably, oxidative addition of PhSH to [Mn(CO)4]? was followed by a Lewis acid-base reaction to form cis-[Mn(CO)4(SPh)2]? with evolution of H2.  相似文献   

14.
Resonant excitation energy transfer from [Cr(ox)3]3? to [Cr(bpy)3]3+ in the doped 3D oxalate networks [Rh1?xCrx(bpy)3][NaMIII1?yCry(ox)3]ClO4 (ox=C2O4?, bpy=2,2′‐bipyridine, M=Al, Rh) is due to two types of interaction, namely super exchange coupling and electric dipole–dipole interaction. The energy transfer probability for both mechanisms is proportional to the spectral overlap of the 2E→4A2 emission of the [Cr(ox)3]3? donor and the 4A22T1 absorption of the [Cr(bpy)3]3+ acceptor. The spin‐flip transitions of (pseudo‐)octahedral Cr3+ are known to shift to lower energy with increasing pressure. Because the shift rates of the two transitions in question differ, the spectral overlap between the donor emission and the acceptor absorption is a function of applied pressure. For [Rh1?xCrx(bpy)3][NaM1?yCry(ox)3]ClO4 the spectral overlap is thus substantially reduced on increasing pressure from 0 to 2.5 GPa. As a result, the energy transfer probability decreases with increasing pressure as evidenced by a decrease in the relative emission intensity from the [Cr(bpy)3]3+ acceptor.  相似文献   

15.
Tetra-azidodiamminecobaltates(III): cis-[Co(N3)4(NH3)2]? and [Co(N3)4en]? The preparation and the properties of complexes containing the anions cis-[Co(N3)4(NH3)2]? and [Co(N3)4en]? are described. The compounds [Co(NH3)6][Co(N3)4(NH3)2 · H2O], [Co(N3)2(NH3)4][Co(N3)4(NH3)2], [As(C6H5)4][Co(N3)4en], cis- and trans-[Co(N3)2en2][Co(N3)4en] have been isolated.  相似文献   

16.
The 3A23E (3T2) band system of MnO3?4 in Sr5(PO4)3Cl at 4.2 K between 10000 and 12000 cm?1 consists of a single progression with 18 components (average frequence 94.5 cm?1) and a double-humped distribution of Franck-Condon factors. as predicted for the vibronic interaction of an E electronic state with an e vibrational mode.  相似文献   

17.
Synthesis and Spectroscopical Characterization of Di(halo)phthalocyaninato(1–)rhodium(III), [RhX2Pc1?] (X = Cl, Br, I) Bronze-coloured di(halo)phthalocyaninato(1–)-rhodium(III), [RhX2Pc1?] (X = Cl, Br) and [RhI2Pc1?] · I2 is prepared by oxidation of (nBu4N)[RhX2Pc2?] with the corresponding halogene. Irrespective of the halo ligands, two irreversible electrode reactions due to the first ringreduction (ER = ?0,90 V) and ringoxidation (EO = 0,82 V) are present in the cyclovoltammogram of (nBu4N)[RhX2Pc2?]. The optical spectra show typical absorptions of the Pc1?-ligand at 14.0 kK and 19.1 kK. Characteristic vibrational bands are at 1 366/1 449 cm?1 (i. r.) and 569/1 132/1 180/1 600 cm?1 (resonance Raman (r. r.)). The antisym. (Rh? X)-stretching vibration is observed at 294 cm?1 (X = Cl), 240 cm?4 (Br) and 200 cm?1 (I). Only the sym. (Rh? I)-stretching vibration at 133 cm?1 is r. r. enhanced together with a strong line at 170 cm?1, which is assigned to the (I? I)-stretching vibration of the incorporated iodine molecule. Both modes show overtones and combinationbands.  相似文献   

18.
Syntheses and Crystal Structures of the Rare-Earth Complexes [LaI2(THF)5]+I3?, [SmCl3(THF)4], [ErCl2(THF)5]+ [ErCl4(THF)2]?, [ErCl3(DME)2], and [Na(18-Crown-6)(THF)2]+[YbBr4(THF)2]? [LaI2(THF)5]+I3? ( 1 ) is obtained as red crystals from lanthanum powder and 1,2-diiodoethane in THF on exposure to light. Space group Pbcn, Z = 4, lattice dimensions at ?83°C: a = 1264.9, b = 2218.9, c = 1199.1 pm, R = 0.031. The lanthanum atom of the cation of 1 is coordinated with iodine atoms in the axial positions in a pentagonal-bipyramidal way. [SmCl3(THF)4] ( 2 ) originates as colourless crystals on heating SmCl3 with excess THF in the presence of Me3SiNPEt3. Space group P21/c, Z = 8, lattice dimensions at ?50°C: a = 3092.7, b = 826.2, c = 1758.3 pm, β = 93.85°, R = 0.054. Just like the known sample that crystallizes within the space group F2dd, 2 forms monomeric molecules in which the samarium atom is coordinated with two chlorine atoms in the axial positions in a distorted pentagonal-bipyramidal way. [ErCl2(THF)5]+[ErCl4(THF)2]? ( 3 ). Pale pink single crystals of 3 were prepared according to the described method by reaction of erbium powder with trimethylchlorosilane and methanol in THF. Space group C2/c, Z = 4, lattice dimensions at ?50°C: a = 1246.3, b = 1145.7, c = 2726.0 pm, β = 91.293°, R = 0.036. The erbium atom of the cation of 3 has a pentagonal-bipyramidal coordination with the chlorine atoms in the axial positions. Within the anion the THF molecules are in trans-arrangement of the octahedrally coordinated erbium atom. [ErC13(DME)2] ( 4 ) originates as pink single crystals from 3 with excess boiling 1,2-dimethoxyethane. Space group P21/c, Z = 4, lattice dimensions at ?50°C: a = 1137.2, b = 886.5, c = 1561.1 pm, β = 104.746°, R = 0.032. 4 forms monomeric molecules in which the erbium atom has a pentagonal-bipyramidal surrounding with two chlorine atoms in the axial positions. [Na(18-Krone-6)(THF)2]+ [YbBr4(THF)2]? ( 5 ) is formed as by-product by the reaction of YbBr3 with NaN(SiMe3)2 in THF in the presence-of 18-crown-6 forming colourless crystals. Space group P1 , Z = 1, lattice dimensions at ?70°C: a = 934.6, b = 988.9, c = 1208.0 pm, α = 73.82°, β = 72.98°, γ = 76.89°, R = 0.029. 5 contains isolated [YbBr4(THF)2]?ions, in which the THF molecules are arranged in trans-position.  相似文献   

19.
New Polynuclear Indium Nitrogen Compounds – Synthesis and Crystal Structures of [In4X4(NtBu)4] (X = Cl, Br, I) and [In3Br4(NtBu)(NHtBu)3] The reaction of the indium trihalides InX3 (X = Cl, Br, I) with LiNHtBu in THF leads to the In4N4‐heterocubanes [In4X4(NtBu)4] (X = Cl 1 , Br 2 , I 3 ). Additionally [In3Br4(NtBu)(NHtBu)3] ( 4 ) was obtained as a by‐product in the synthesis of 2 . 1 – 4 have been characterized by x‐ray crystal structure analysis. 1 – 3 consist of In4N4 heterocubane cores with an alternating arrangement of In and N atoms. The In atoms are coordinated nearly tetrahedrally by three N‐atoms and a terminal halogen atom. 4 contains a tricyclic In3N4 core which can be formally derived from an In4N4‐heterocubane by removing one In atom.  相似文献   

20.
The behaviour of Na[HCO2], Na[HCOS], and K[HCS2] in aqueous solutions between 4 and 42°C was investigated by means of conductivity measurements. The equivalent conductivities Λ of [HCO2]?, [HCOS]?, and [HCS2]? and the dissociation constants Kc of HCOSH and HCSSH were determined. The STOKES radii of the ions, the radii of the hydrated ions, and their diffusion coefficients were calculated.  相似文献   

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