Darstellung und Charakterisierung von bindungsisomeren Hexakis-(thiocyanato-isothiocyanato)-rhodaten(III) und Di-μ-thiocyanato-N,S-octathiocyanatodirhodat(III)

Preparation and Characterization of Bond-Isomeric Hexakis-(thiocyanato-isothiocyanato)rhodates(III) and Di-μ-thiocyanato-N, S-octathiocyanatodirhodate (III) The reaction of RhCl₃ with an aqueous solution of KSCN does not yield pure [Rh(SCN)₆]^3? as is supposed until now but a mixture of the bond isomers [Rh(NCS)_n(SCN)_6?n]^3?, n = 0–3. By heating the tetrabutylammonium salts N coordination of the ambident SCN^? is favoured forming mixtures with n = 0–4. The pure bond isomers are separated by ion exchange chromatography on diethylaminoethyl cellulose. Extracting the mixture (n = 0–3) with triphenylphosphiniminiumchloride from water into CH₂Cl₂ [Rh₂(SCN)₁₀]^4? is formed, containing two Rh? SCN? Rh bridges and exclusively S-coordinated terminal ligands. Depending on S or N bonding the IR and Raman spectra show typical vibrations: ν_CN(N) and ν_CN(S): 2095–2170, ν_CS(N): 810–835, ν_CS(S): 695–710, δ_NCS: 460–470, δ_SCN: 425–465, ν_RhN: 300–340, ν_RhS: 265–306 cm^?1. The application of group theory indicates that for n = 2 and 4 the cis-, for n = 3 the mer-compound exists. Except the inner ligand vibrations the Rh? N and Rh? S valence vibrations are assigned according to the supposed point symmetries. By interaction of trans-positioned ligands characteristic shifts are caused. The isolated complexes may also be distinguished and identified by their electronic spectra.     

Schwingungs- und Elektronenspektren der bindungsisomeren Hexakis(thiocyanato-isothiocyanato)-ruthenate(III)

Vibrational and Electronic Spectra of Bond-Isomeric Hexakis(thiocyanato-isothiocyanato)ruthenates(III) Well resolved IR, Raman, and Electronic spectra of the bond isomeric complexes (TBA)₃[Ru(NCS)_n(SCN)_6?n], n = 1–5, including the pairs of geometric isomers n = 2, 3, 4, are recorded at low temperatures (10 and 80 K). Characteristic vibrations of the N- or S-coordinated ambident ligand SCN^? occur as listed: ν_CS(N): 810–850, ν_CS(S): 690–710, δ_NCS: 450–490, δ_SCN: 420–450, ν_RuN: 300–350, ν_RuS: 270–295 cm^?1. The assignment of the complexes is based on stepwise increasing intensities of the ν_CS(N) modes with increasing number of N-coordinated ligands. Characteristic shifts and splittings in the spectra allow to distinguish the geometric bond isomers according to their different symmetries. Even the absorption spectra in the visible range show within the series of bond isomers and for the cis/trans pairs systematic alternations.     

Darstellung und spektroskopische Charakterisierung der reinen Bindungsisomeren [OsCl5(NCS)]2− und [OsCl5(SCN)]2−

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 ν_CN(S), ν_CS(N) and δ_NCS are found at higher wave numbers than ν_CN(N), ν_CS(S) and δ_SCN. 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 χ_opt(–SCN) = 2.6 and χ_opt(–NCS) = 2.6–2.8. According to spinorbit coupling and to lowered symmetry (C_4v) 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(Os^IV) = 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^?.     

Darstellung und spektroskopische Charakterisierung der reinen Bindungsisomeren [ReX5(NCS)]2− und [ReX5(SCN)]2−, X = Cl,Br

Preparation and Spectroscopic Characterization of the Pure Bondisomers [ReX₅(NCS)]^2? and [ReX₅(SCN)]^2?, X = Cl, Br The treatment of (TBA)₂[ReBr₆] with NaSCN in acetone or of (TBA)₂[ReCl₅I] with AgSCN in CH₂Cl₂ yields mixtures of the bondisomers [ReBr₅(NCS)]^2?/[ReBr₅(SCN)]^2? or [ReCl₅(NCS)]^2?/[ReCl₅(SCN)]^2?, which are isolated as pure compounds by ion exchange chromatography on DEAE-Cellulose. The i.r. and Raman spectra are assigned according to local symmetry C_4v. The bondisomers are significantly distinguished by the frequencies of inner ligand vibrations: ν_CN(S) > ν_CN(N), ν_CS(N) > ν_CS(S), δ_NCS > δ_SCN. The electronic absorption spectra measured at 10 K exhibit in the region 6000 to 16000 cm^?1 all intraconfigurational transitions (t) splitted into Kramers dubletts by lowered symmetry (C_4v) and spin orbit coupling. The O? O transitions are deduced from vibrational fine structure. The charge transfer spectra of the bondisomers in the UV/VIS region are similar to those of the corresponding hexahalorhenates(IV).     

Darstellung und Charakterisierung von Bindungsisomeren Bromorhodanorhenaten(IV)

Preparation and characterization of bondisomeric bromorhodanorhenates(IV) The new compounds [ReBr₅(SCN)]^2?, [ReBr₅(NCS)]^2?, cis/tr.-[ReBr₄(NCS)(SCN)]^2?, cis-[ReBr₄(NCS)₂]^2?, mer-[ReBr₃(NCS)₃]^2? are prepared from [ReBr₆]^2? by ligand exchange with NaSCN, KSCN, or (SCN)₂ in organic solvents and isolated by ion exchange chromatography on DEAE cellulose. The bondisomers are significantly distinguished by the frequencies of inner ligand vibrations: v_CN(S) > v_CN(N), v_CS(N) > v_CS(S), δ_NCS δ_SCN. The electronic absorption spectra measured at 10 K exhibit in the region 5700 to 15300 cm^?1 all intraconfigurational transitions (t_2g³) splitted into 8 Kramers doublets by lowered symmetry (C_4v, C_2v, C_s) and spin orbit coupling. The O–O-transitions are deduced form vibrational fine structure and confirmed by electronic Raman bands in some cases. The magnetic moments are in the range of 3.0 to 3.9 B.M.     

Darstellung und spektroskopische Charakterisierung von Bindungsisomeren Halogenoselenocyanatoosmaten(IV)

Preparation and Spectroscopic Characterization of Bondisomeric Halogenoselenocyanatoosmates (IV) The new compounds [OsCl₅(NCSe)]^2?, [OsCl₅(SeCN)]^2?, tr.-[OsCl₄(NCSe)(SeCN)]^2?, tr.-[OsCl₄I(NCSe)]^2? and tr.-[OsCl₄I(SeCN)]^2? are prepared from [OsCl₅I]^2? and tr.-[OsCl₄I₂]^2? by oxidative ligand exchange with (SeCN)₂ or by reaction with suspended Pb(SeCN)₂ in CH₂Cl₂ and isolated by ion exchange chromatography on DEAE cellulose. The bondisomers are significantly distinguished by the frequencies of innerligand vibrations: ν_CN(Se), ν_CN(N), ν_CSe(N) > ν_CSe(Se), δ_NCSe >, δ_SeCN. The electronic spectra measured at 10 K on the solid salts exhibit in the region 450–650 nm intensive Se → Os and N → Os charge transfer bands. Essentially weaker intraconfigurational transitions (t) are observed near to 2000 and 1000 nm, splitted by lowered symmetry (C_4v) and spin orbit coupling. Only some of the 0–0-transitions may be assigned by measuring electronic Raman bands with the same frequencies.     

Darstellung und spektroskopische Charakterisierung von Di(acido)phthalocyaninatorhodaten(III)

Preparation and Spectroscopical Characterization of Di(acido)phthalocyaninatorhodates(III) Triethylendiaminorhodiumiodide reacts quickly and completely with boiling phthalodinitrile precipitating ?rhodiumphthalocyanine”?, which is purified and dissolved in alkaline media as di(hydroxo)phthalocyaninatorhodate(III). Acidification in the presence of halides or pseudohalides yields less soluble acidophthalocyaninatorhodium reacting with tetra-n-butyl-ammonium(pseudo)halide to give (blue)green tetra-n-butyl-ammoniumdi(acido)phthalocyaninatorhodate(III), (ⁿBu₄N)[Rh(X)₂Pc^2?] (X = Cl, Br, I, N₃, CN, NCO, SCN, SeCN). The asym. Rh? X-stretching vibration (v_as(RhX)) is observed in the f.i.r. at 290 (X = Cl), 233 (Br), 205 (I), 366 (N₃), 347 (CN), 351 (NCO), 257 (SCN) and 214 cm^?1 (SeCN). v_s(RhI) is the only sym. Rh? X-stretching vibration excited at 131 cm^?1 in the Raman spectrum. The m.i.r. and resonance Raman spectra are typical for hexacoordinated phthalocyaninatometalates(III). The influence of the axial ligands is very small. The frequency of the stretching vibrations of the pseudohalo-ligands are as expected (in the case of the ambident ligands the bonding atom is named first): v_as(NN) at 2006 and v_s(NN) at 1270 cm^?1 (N₃); v_as(CN) at 2126 (CN), 2153 (NCO), 2110 (SCN) and 2116 cm^?1 (SeCN). The characteristic π–π*-transitions of the Pc^2?-ligand dominate the UV-vis spectra. The splitting of the Q and N region is discussed and the weak absorbance at ca. 22 kK is assigned to a n–π*-transition.     

Darstellung und spektroskopische Charakterisierung von bindungsisomeren Halogenorhodanoosmaten(IV)

Preparation and Spectroscopic Characterization of Bond-Isomeric Halogenorhodanoosmates(IV) By oxidation of tr.-[OsCl₄BrI]^2? or tr.-[OsCl₄I₂]^2? with (SCN)₂ in CH₂Cl₂, by substitution of [OsCl₅I]^2? with SCN^? or [OsCl₅(NCS)]^2? with F^? in toluene and by reaction of [OsF₅Cl]^2? with (SCN)₂ in CH₂Cl₂ the following bondisomers are prepared: tr.-[OsF₄Cl(NCS)]^2?/tr.-[OsF₄Cl(SCN)]^2?, tr.-[OsFCl₄(NCS)]^2?/tr.-[OsFCl₄(SCN)]^2?, tr.-[OsCl₄Br(NCS)]^2?/tr.-[OsCl₄Br(SCN)]^2?, tr.-[OsCl₄I(NCS)]^2?/tr.-[OsCl₄I(SCN)]^2?,tr.-[OsCl₄(NCS)₂]^2?/tr.-[OsCl₄(NCS)(SCN) ]^2?/tr.-[OsCl₄(SCN)₂]^2?, [OsBr₅(NCS)]^2?/[OsBr₅(SCN)]^2? and tr.-[OsBr₄(NCS)(SCN)]^2?. All complexes are isolated as pure compounds by ion exchange chromatography on DEAE-cellulose. In the IR and Raman spectra ν_CN(S), ν_CS(N) and δ_NCS are found at higher wave numbers than ν_CN(N), ν_CS(S) and δ_SCN. According to spin orbit coupling and to lowered symmetry (D_4h, C_4v) the splitted intraconfigurational transitions are observed at 10 K as weak bands in the regions 600, 1000, 2000 nm. The O? O transitions are calculated from vibrational fine structure and in some cases are confirmed by electronic Raman bands with the same frequencies. The energy niveaus deduced with ζ(Os^IV) = 3200 cm^?1 and the calculated Racah parameters B are in good agreement with the barycenters of the observed multiplets for D_4h and C_4v symmetry.     

Darstellung,Eigenschaften und elektronische Raman-Spektren von Bis(chloro)phthalocyaninatoferrat(III), -ruthenat(III) und -osmat(III)

Preparation, Properties and Electronic Raman Spectra of Bis(chloro)-phthalocyaninatoferrate(III), -ruthenate(III) and -osmate(III) Bis(chloro)phthalocyaninatometalates of Fe^III, Ru^III and Os^III [MCl₂Pc(2-)]^?, with an electronic low spin ground state are formed by the reaction of [FeClPc(2-)] resp. H[MX₂Pc(2?)] (M = Ru, Os; X = Cl, I) with excess chloride in weakly coordinating solvents (DMF, THF) and are isolated as (n-Bu₄N) salts. The asym. M? Cl stretch (ν_as(MCl)) is observed in the f.i.r. at 288 cm^?1 (Fe), 295 cm^?1 (Ru), 298 cm^?1 (Os), ν_as(MN) at 330 cm^?1 (Fe), 327 cm^?1 (Ru), and 317 cm^?1 (Os); only ν_s(OsCl) at 311 cm^?1 is resonance Raman (r.r.) enhanced with blue excitation. The m.i.r. and FT-Raman spectra are typical for hexacoordinated phthalocyanines of tervalent metal ions. The UV-vis spectra show besides the characteristic π-π* transitions (B, Q, N, L band) of the Pc ligand a number of extra bands at 12–15 kK and 18–24 kK due to trip-doublet and (Pc→M)CT transitions. The effect of metal substitution is discussed. The r.r. spectra obtained by excitation between the B and Q band (λ₀ = 476.5 nm) are dominated by the intraconfigurational transition Γ₇ Γ ₈ arrising from the spin-orbit splitting of the electronic ground state for Fe^III at 536 cm^?1, for Ru^III at 961 cm^?1 and Os^III at 3 028 cm^?1. Thus the spin-orbit coupling constant increases very greatly down the iron group: Fe^III (357 cm^?1)< Ru^III (641 cm^?1)< Os^III (2 019 cm^?1). The Γ₇ Γ ₈-transition is followed by a very pronounced vibrational finestructure being composed in the r.r. spectra by the coupling with ν_s(MCl), δ(MClN) and the most intense fundamental vibrations of the Pc ligand. In absorption only vibronically induced transitions are observed for the Ru and Os complex at 1 700-2800 rsp. 3100-5800 em^?1 instead of the 0-0 phonon transitions. The most intense lines are attributed to combinations of the intense odd vibrational mo-des at ≈ 740 and 1120 cm^?1 with ν₅(MCI), δ(MClN).     

Darstellung und spektroskopische Charakterisierung von bindungsisomeren Halogenoselenocyanato-Osmaten(IV) und -Rhenaten(IV)

Preparation and Spectroscopic Characterization of Bond Isomeric Halogenoselenocyanato-Osmates(IV) and -Rhenates(IV) By oxidative ligand exchange of appropriate chloro-iodo complexes of Os^IV or Re^IV with (SeCN)₂ in CH₂Cl₂ or by heterogeneous reaction with Pb(SeCN)₂ or AgSeCN in CH₂Cl₂ the new complexes cis-[OsCl₄(NCSe)(SeCN)]^2?, tr.-[OsCl₄Br(NCSe)]^2?, tr.-[OsCl₄Br(SeCN)]^2?, [ReCl₅(NCSe)]^2?, [ReCl₅(SeCN)]^2?, tr.-[ReCl₄I(NCSe)]^2?, tr.?[ReCl₄(NCSe)(SeCN)]^2? and tr.?[ReCl₄(NCSe)₂]^2? are formed and isolated as pure compounds by ion exchange chromatography on DEAE-cellulose. The bond isomers are significantly distinguished by the frequencies of innerligand vibrations: n?_CN(Se) > n?_CN(N); n?_CSe(N) > n?_CSe(Se); δ_NCSe > δ_SeCN. The electronic spectra (10 K) of the solid salts reveal a bathochromic shift for the charge transfer bands of the Se isomers as compared with the corresponding N isomers. The intra-configurational transitions are observed for the Os^IV complexes at 600 to 2400 and for the Re^IV complexes at 500 to 1600 nm. The ⁷⁷Se nmr signals of the Os^IV bond isomers are registrated for Se binding in the region 970 to 1040 ppm, for N coordination downfield at 1540 to 1640 ppm.     

Über bismut-haltige heterocyclen: I. Methylierte und phenylierte bismocane,intra- und intermolekulare koordinationserhöhung an bismut(III)

Methyl and phenyl oxadithia and trithiabismocanes have been synthesized from methyl or phenyl diethoxybismutane and the respective dithiol. The light-sensitive compounds have been investigated by mass, vibrational and ¹³C NMR spectra: ν(BiMe) 470–460, ν(BiS₂) 300–240 cm^?1; δ(¹³Me) ?12 ppm. The crystal structure of 5-phenyl-1,4,6,5-oxadithiabismocane has been determined (R = 0.056). The eight-membered ring has the chair-chair conformation. Besides three direct bonds (BiPh 225(2), BiS 256.0(2) and 260.2(3) pm) there are one transannular (Bi?O 297(1) and two intermolecular contacts (Bi ?S 344.0(3) and 350.9(3) pm) to bismuth in resulting a ψ-monocapped octahedral sphere of coordination. These polyhedra are connected in sharing two different edges, and the crystal structure exhibits double chains of molecules.     

Synthese und spektroskopische Charakterisierung von [Rh(SeCN)6]3– und trans‐[Rh(CN)2(SeCN)4]3–, Kristallstruktur von (Me4N)3[Rh(SeCN)6]

Synthesis and Spectroscopic Characterization of [Rh(SeCN)₆]^3– and trans ‐[Rh(CN)₂(SeCN)₄]^3–, Crystal Structure of (Me₄N)₃[Rh(SeCN)₆] Treatment of RhCl₃ with KSeCN in acetone yields a mixture of selenocyanato‐rhodates(III), from which [Rh(SeCN)₆]^3– and trans‐[Rh(CN)₂(SeCN)₄]^3– have been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X‐ray structure determination on a single crystal of (Me₄N)₃[Rh(SeCN)₆] (trigonal, space group R3, a = 14.997(2), c = 24.437(3) Å, Z = 6) reveals, that the compound crystallizes isotypically to (Me₄N)₃[Ir(SCN)₆]. The exclusively via Se coordinated selenocyanato ligands are bonded with the average Rh–Se distance of 2.490 Å and the Rh–Se–C angle of 104.6°. In the low temperature IR and Raman spectra the metal ligand stretching modes ν(RhSe) of (n‐Bu₄N)₃[Rh(SeCN)₆] ( 1 ) and trans‐(n‐Bu₄N)₃[Rh(CN)₂(SeCN)₄] ( 2 ) are in the range of 170–250 cm^–1. In 2 ν_as(CRhC) is observed at 479 cm^–1. The vibrational spectra are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are f_d(RhSe) = 1.08 ( 1 ), 1.10 ( 2 ) and f_d(RhC) = 3.14 mdyn/Å ( 2 ). f_d(RhS) = 1.32 mdyn/Å is determined for [Rh(SCN)₆]^3–, which has not been calculated so far. The ¹⁰³Rh NMR resonances are 2287 ( 1 ), 1680 ppm ( 2 ) and the ⁷⁷Se NMR resonances are –32.7 ( 1 ) and –110.7 ppm ( 2 ). The Rh–C bonding of the cyano ligand in 2 is confirmed by a dublett in the ¹³C NMR spectrum at 136.3 ppm.     

Darstellung und Kristallstruktur von Tetraphenylphosphonium-Hexathiocyanatorhodat(III), [P(C6H5)4]3[Rh(SCN)6]

Preparation and Crystal Structure of Tetraphenylphosphonium Hexathiocyanatorhodate(III), [P(C₆H₅)₄]₃[Rh(SCN)₆] By treatment of RhCl₃ · n H₂O with KSCN in water a mixture of the linkage isomers [Rh(NCS)_n(SCN)_6–n]^3?, n = 0–2 is formed which is separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on a single crystal of [P(C₆H₅)₄]₃[Rh(SCN)₆] (monoclinic, space group C1c1, a = 13.620(5), b = 22.929(13), c = 22.899(9) Å, β = 98.55(3)°, Z = 4) confirms the coordination of all ligands via S with the middle Rh? S distance of 2.372 Å and Rh? S? C angles of 109°. The SCN groups are nearly linear with 175° and averaged bondlengths S? C 1.63 and C? N 1.14 Å. The crystal lattice is build up by layers of complex anions and voluminous cations with no specific interactions but which are closely connected by thiocyanate ligands and phenyl rings.     

Low-spin Manganphthalocyanine: Darstellung,Eigenschaften und elektronisches Raman-Spektrum von Di(cyano)phthalocyaninatomanganat(III) und -(II)

Low Spin Manganese Phthalocyanines: Preparation, Properties and Electronic Raman Spectrum of Di(cyano)phthalocyaninatomanganate(III) and -(II) . Iodophthalocyaninatomanganese(III) reacts with cyanide in acetone to yield di(cyano)phthalocyaninatomanganate(II), in dichloromethane, however di(cyano)phthalocyaninatomanganate(III) is formed. Both complexes are isolated as (n-Bu₄N)-salts. In the cyclovoltammogram the redox couple Mn^II/Mn^III is attributed to E_1/2 = - 0.22 V and the first ringoxidation Pc(2 -)/Pc(1 -) to E_1/2 = 0.75 V. The paramagnetic salts have magnetic moments (μ_eff = 2.11 resp. 2.95 B.M.) typical for the low spin ground state of Mn^II resp. Mn^III (S = 1/2 resp. 1). The uv-vis-nir spectra are discussed. Comparison with the dicyano-complexes of Cr^III, Fe^II/III and Co^III indicates that the multiple “extra bands” between 4 and 23 kK should be assigned to spin allowed trip-multiplets. The vibrational spectra are discussed. ν_as(Mn? C)(a_2u) is found at 350 cm^?1, ν_as(C? N)(a_2u; cyanide) at 2 092 (Mn^II) and 2 114 cm^?1 (Mn^III). The Raman spectra are dominated by resonance Raman(RR) effects. With variable-wavelength excitation polarized, depolarized and anomalously polarized vibrations assigned to phthalocyanine skeletal modes are selectively RR-enhanced for the Mn^II complex. Intensive lines between 1 650 and 3 300 cm^?1 are due to combinations and overtones of the a_2g vibrations at 1 492 and 1 602 cm^?1. In the 10 K Raman spectrum of (n-Bu₄N)[Mn(CN)₂Pc(2 -)] intraconfigurational transitions Γ₁ → Γ₄ and Γ₁ → Γ₃, Γ₅ resulting from the splitting of the ³T_1g ground state of Mn^III (O_h symmetry) by spin-orbit coupling are observed as anomalously polarized and depolarized lines at 172 and 287 cm^?1.     

Darstellung und spektroskopische Eigenschaften der gemischtvalenten Di(phthalocyaninato)lanthanide(III)

Synthesis and Spectroscopical Properties of the Mixed-Valent Di(phthalocyaninato)lanthanides(III) Green di(phthalocyaninato)lanthanide(III), [M(Pc)₂] (M = rare earth metal ion: La‥(-Ce, Pm)‥Lu) is prepared by anodic oxidation of (ⁿBu₄N)[M(Pc^2?)₂] dissolved in CH₂Cl₂/(ⁿBu₄N)ClO₄. The UV-Vis-NIR spectra show intense π-π* transitions at ? 15000 cm^?1 and 31000 cm^?1, typical for Pc^2? ligands. Bands at ? 11000 cm^?1 and 22000 cm^?1 indicate the equal presence of a Pc^? π-radical. The metal dependent NIR band between 4000 and 9000 cm^?1 is characteristic for these mixed-valent complexes and assigned to an intervalence transition (b₁ → a₂; D_4d symmetry). Most bands are shifted linearly with the M^III radius. In the IR and resonance Raman (r.r.) spectra the typical vibrations of the Pc^? π-radical are dominant. These are essentially metal independent excepting the C? C and C? N vibrations of the inner (CN)₈ ring. The sym. M? N stretching vibration between 141 (La) and 168 cm^?1 (Lu) is selectively r.r.-enhanced when excited with 1064 nm.     

Dimere low-spin Eisen(III)-Phthalocyanine: Synthese und Eigenschaften ferromagnetisch gekoppelter μ-Oxodi(acidophthalocyaninatoferrate(III))

Dimeric Low-Spin Iron(III) Phthalocyanines: Synthesis and Properties of Ferromagnetically Coupled μ-Oxodi(acidophthalocyaninatoferrates(III)) μ-Oxodi(phthalocyaninatoiron(III)) ([(FePc^2?)₂O]) dissolved in pyridine reacts with different Tetra(n-butyl)ammonium salts yielding partly solvated Di(tetra(n-butyl)ammonium)-μ-oxodi(acidophthalocyaninatoferrates(III)) ((ⁿBu₄N)₂[(Fe(X)Pc^2?)₂O]; X^? = CN^?, Im^?, NCO^?, NCS^?, NO₂^?). The uv-vis. spectra show the typical B, Q, N and L regions of the Pc^2? ligand scarcely influenced by the axial ligands X. In comparison with [(FePc^2?)₂O] mainly the B region is hypsochromically shifted due to strong excitonic coupling (> 3 kK). Two regions of weak absorbance at ca. 7.6–8.7 and 11.4–13.0 kK are assigned to trip-doublet transitions. The m.i.r. and resonance Raman spectra are dominated by the fundamental vibrations of the Pc^2? ligand being characteristic for hexa-coordinated low-spin Fe^III phthalocyanines. Internal vibrations of the ambident axial ligands X are in accordance with the proposed Fe? X bond. The i.r. active asym. (Fe? O? Fe) stretching vibration is observed in the region 631–690 cm^?1. Fe? X stretching vibrations are only present in the f.i.r. spectra. The magnetic properties and Mößbauer spectra are interpreted in terms of an electronic model which assumes that a S′ = 1 ground state arises from strong ferromagnetic coupling of the low-spin Fe^III centres. Both spin-Hamiltonian and ligand-field models have been employed to fit the variable temperature susceptibility data. These low-spin μ-oxo Fe^III dimers are rare compared to the many known examples of coupled high-spin species including the parent, [(FePc^2?)₂O].     

Spektroskopische Eigenschaften von Di(phthalocyaninato)metallaten(III) der Seltenen Erden Teil 1: Elektronische Absorptionsspektren und Schwingungsspektren

Spectroscopical Properties of Di(phthalocyaninato)metalates(III) of the Rare Earth Elements. Part 1: Electronic Absorption and Vibrational Spectra Di(phthalocyaninato)metalates(III) of the rare earth elements were prepared by the reaction of partially dehydrated lanthanide acetate with molten phthalodinitrile in the presence of potassium methylate and isolated as complex salts with different tetraalkylammonium cations, especially tetra(n-butyl)- and tri(n-dodecyl)n-octylammonium and di((triphenyl)phosphine)-iminium (abbrev.: (ⁿBu₄N), TDOA, PNP). Besides the typical strong π-π* transitions in the B, Q, N regions of the Pc^2? ligands low intensity bands at ca. 10, 11 and 19 kK are observed in the UV-Vis-NIR spectra and assigned to singulet–triplet transitions. In going from La to Lu the B band splits continously due to excitonic coupling extending from 0,71 (La) to 1,92 kK (Lu). The FIR-MIR and resonance Raman spectra are nearly metal independent with the exception of some hypsochromically shifted bands due to C? C and C? N stretching and deformation vibrations of the inner (CN)₈ ring. Only the FIR band at 157 cm^?1 (La) assigned to the asym. Ln? N stretching vibration is shifted to lower energy.     

Darstellung und spektroskopische Charakterisierung der Nona-halogenodiiridate(III), [Ir2X9]3−, X = Cl,Br

Preparation and Spectroscopic Characterization of Nonahalogenodiiridates(III), [Ir₂X₉]^3?, X = Cl, Br The pure nonahalogenodiiridates(III), A₃[Ir₂X₉] (A = K, Cs, tetraalkylammonium; X = Cl, Br) have been prepared. They are formed from the monomer hexahalogenoiridates(III) which are bridged to confacial bioctahedral complexes by ligand abstraction in less polar organic solvents. The IR and Raman spectra exhibit bands in three characteristic regions; at high wavenumbers stretching vibrations with terminal ligands ν(Ir?Cl_t): 360?300, ν(Ir?Br_t): 250?220; in a middle region with bridging ligands ν(Ir?Cl_b): 290?235, ν(Ir?Br_b): 205?190 cm^?1; the deformation bands are observed at distinct lower frequencies. The distance between ν(Ir?X_t) and ν(Ir?X_b) increases with decreasing size of the cations. The electronic spectra measured at thin films of the pure complex salts at 10 K show some intensive charge transfer transitions in the UV and one or two weak d? d bands in the visible region.     

Darstellung und Schwingungsspektren von Chloro-Bromo-Dirhodaten(III), [Rh2ClnBr9−n]3−, n = 0–9

Preparation and Vibrational Spectra of Nonahalogenodirhodates(III), [Rh₂Cl_nBr_9-n]^3?, n = 0–9 The pure nonahalogenodirhodates(III), A₃[Rh₂Cl_nBr_9-n], A = K, Cs, (TBA); n = 0–4, 9, have been prepared. They are formed from the monomer chlorobromorhodates(III), [RhCl_nBr_6-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 [Rh₂Cl_nBr_9-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 D_3h. 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—Cl_t): 360–320, v(Rh—Br_t): 280–250; in a middle region with bridging ligands v(Rh—Cl_b): 300–270, v(Rh—Br_b): 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—X_t) and v(Rh—X_b) increases with decreasing size of the cations.     

Cobalt- und Rhodiumphthalocyanine mit O-, S- und Se-Donorliganden

Phthalocyanines of Cobalt and Rhodium with O, S, and Se Donor Ligands Di(phenolato)-, -(benzenethiolato)- and -(benzeneselenonato)phthalocyaninatocobaltate(III) and -rhodate(III) are prepared by the reaction of di(hydroxo)phthalocyaninatometalate with phenol resp. benzenethiol or benzeneselenol and isolated as poorly soluble tetra(n-butyl)ammonium salts of the formula (ⁿBu₄N)[M(EPh)₂Pc^2?] (M = Co, Rh; E = O, S, Se). In the Uv-vis spectra π–π* transitions in the Pc^2?-typical B, Q, N and L regions are observed. For the Rh-complexes with E = S, Se there is a further band at 18.0 kK due to excitonic π(Ph)–π(Pc) interactions. The (E→Rh-charge-transfer(CT)) transition is observed for E = Se at 26.0 kK, being obscured by the Q, N region for E = O, S. The strong, broad (E → Co? CT) transition (E = O, S, Se) absorbs at ～20.5 kK. A second CT-transition is detected within the Q, N region for E = S, Se. Molecular vibrations (in cm^?1) are examined by m.i.r., f.i.r, FT-Raman and dispersive resonance-Raman(RR) spectra. The C? E stretching mode (v_7a) of the axial EPh ligands is observed for E = O at 1256/1262, 1269 (Co, m.i.r./RR), 1246/1265 (Rh), for E = S at 1085 (Co, Rh; RR) and for E = Se at 1069 (Co, Rh; RR). The C? C? E deformation mode (v_6a) is assigned for E = O at 554/557 (Co, RR), 568 (Rh, RR) and for E = S at 420 (Co, Rh; RR). The following vibrational modes of the trans-ME₂N₄ skeleton are assigned: v_s(ME) for Co: 381 (O)/271 (S)/139 (Se); for Rh: 408/297/156; v_as(ME) for Co: 352/277/235; for Rh: 391/278/225; v_as(MN) absorbs nearly independent of M and E at ～325 (f.i.r.) M? E? C deformation modes are observed between 246 and 200 (f.i.r.) resp. 217 and 186 (RR).