Synthese und Eigenschaften von molekularen Leitern auf der Basis von dmit-isologen Chelaten Kristall- und Molekülstruktur des Tetramethylammonium-bis-[bis-(1,3-dithiol-2-selon-4,5-diselenolato)nickelat]; [(CH3)4N][Ni(dsise)2]2

Syntheses and Properties of Molecular Conductors based on dmit isologous Chelates. Crystal and Molecular Structure of Tetramethylammonium-bis-[bis(1,3-dithiole-2-selone-4,5-diselenolato)nickelate]; [(CH₃)₄N] [Ni(dsise)₂]₂ Syntheses and properties of dichalcogenolate chelates of the general type [(CH₃)₄N]_n[ML₂] (n ≤ 2; M = Ni, Pd, Pt); L = dmit (1,3-dithiole-2-thione-4,5-dithiolate), dmise (1, 3-dithiole-2-selone-4,5-dithiolate), dsit (1, 3-dithiole-2-thione-4,5-diselenolate), dsise (1, 3-dithiole-2-selone-4,5-diselenolate), dsis (1, 3-diselenole-2-selone-4,5-diselenolate) are reported. The effects of the chalcogen atom variation in these chelates are discussed by using UV/VIS, IR, EPR, cyclovoltammetric and conductivity data. The x-ray structure of [(CH₃)₄N][Ni(dsise)₂]₂ (space group Pccn, a = 7.427(1), b = 39.144(5), c = 11.836(1) Å) and the conductivity of the crystal (12 S cm^?1 at room temperature) are given.     

Zur Koordinationschemie des 1,3-Dithiol-2-thion-4,5-diselenolats (dsit) – ein Vergleich mit 1,3-Dithiol-2-thion-4,5-dithiolat (dmit)

Coordination Chemistry of 1,3-Dithiole-2-thione-4,5-diselenolate (dsit) — Comparison with 1,3-Dithiole-2-thione-4,5-dithiolate (dmit) Synthesis and properties of metal(II) and/or metal(III) bis-chelates of 1,3-dithiole-2-thione-4,5-diselenolate (dsit) of general type (Bu₄N)_n[M(dsit)₂] (n = 2: M ? Zn, Cd, Hg, Cu, Ni, Pd, Pt; n = 1: M ? Ni, Au) are described. By comparison of the ir, ¹³C nmr, epr spectra, cyclovoltammetric data, and x-ray investigations (nickel-bis-chelates) of chelates of dsit and those of the chelates of 1,3-dithiole-2-thione-4,5-dithiolate (dmit) the consequences of selenium for sulfur substitution on position 4 and 5 of the heterocyclic ligand are discussed.     

Zur Koordinationschemie des 1,3-Thiaselenol-2-thion-4,5-dithiolats (dmits) – ein Vergleich mit 1,3-Dithiol-2-thion-4,5-dithiolat (dmit)

Coordination Chemistry of 1,3-Thiaselenole-2-thione-4,5-dithiolate (dmits) – Comparison with 1,3-Dithiole-2-thione-4,5-dithiolate (dmit) Synthesis and properties of metal(II) and/or metal(III)-bis-chelates of 1,3-thiaselenole-2-thione-4,5-dithiolate (dmits) of the general type (Bu₄N)_n[M(dmits)₂] (n = 2: M = Zn, Cd, Hg, Ni, Cu, Pd; n = 1: M = Au, Ni) are described. By comparison of the i.r., ¹³C-n.m.r., epr spectra and cyclovoltammetric data of chelates of dmits and those of 1,3-dithiole-2-thione-4,5-dithiolate (dmit) the consequences of the substitution of selenium for sulfur on position 3 of the heterocyclic ligand dmit are discussed.     

Neue dimere Goldselenolate: Darstellung und strukturelle Charakterisierung von [(n-C4H9)4N]2[AuSSeCC(CN)2]2 und [(n-C4H9)4N]2[AuSe2CC(CN)2]2

New Dimeric Gold Selenolates: Preparation and Characterization of [(n-C₄H₉)₄N]₂[AuSSeC ? C(CN)₂]₂ and [(n-C₄H₉)₄N]₂[AuSe₂C ? C(CN)₂]₂ The preparation and structural characterization of the dimeric Au^I complexes of 1,1-dicyanoethene-2,2-thioseleonlate (i-mnts) and 1,1-dicyanoethene-2,2-diselenolate (i-mns), isolated as Bu₄N salts, are described. They are isotype (monoclinic, space group P2₁/c, Z = 2) with lattice parameters: (Bu₄N)₂[Au(i-mnts)]₂; a = 14.078(3) Å, b = 8.912(3) Å, c = 20.142(4) Å, β = 106.32(5)°; (Bu₄N)₂[Au(i-mns)]₂; a = 13.998(3) Å, b = 9.125(3) Å, c = 20.039(2) Å, β = 105.12(5)°. Ab initio Hartree-Fock calculations based on the experimentally determined structure yield a positive value of the Au? Au bonding order suggesting weak bonding interactions between the d¹⁰ metal centres.     

Synthese und Charakterisierung von Metallocen-Chelaten heterocyclischer 1,2-Diselenolate

Synthesis and Characterization of Metallocene Chelates of Heterocyclic 1,2-Diselenolates Synthesis and properties of metallocen diselenolates Cp₂^RML (Cp^R = η⁵-C₅H₄CH₃ (Cp′); η⁵-C₅(CH₃)₄ C₂H₅ (Cp^o)) of titanium(IV) and vanadium(IV) with L = dsit (1,3-dithiole-2-thione-4,5-diselenolate), dsise (1,3-dithiole-2-selone-4,5-diselenolate) dsitse (1,3-thiaselenole-2-selone-4,5-diselenolate) and dsis (1,3-diselenole-2-selone-4,5-diselenolate) are described. The structures of these compounds in solution are discussed using ¹H, ¹³C, ⁷⁷Se NMR and EPR data. Their voltammetric behaviour is investigated in dichloromethane. The activation parameters of the chelate ring inversion of the titanocene diselenolates (Cp₂^RTiL) and the x-ray structures of Cp₂′Ti(dsit), Cp₂^oTi(dsit); Cp₂^oTi(dsise) (2 modifications) and Cp₂^oTi(dsis) are reported.     

Darstellung und Kristallstruktur von (n-Bu4N)3[Ir(NCS)(SCN)5]

Preparation and Crystal Structure of (n-Bu₄N)₃[Ir(NCS)(SCN)₅] The evaporated ethanolic extrakt of the reaction product of K₃[IrCl₆] and HNO₃, refluxed with an aqueous KSCN solution yields a mixture of the linkage isomers [Ir(NCS)_n(SCN)_6?-n]^3?, n = 0? 2, and small amounts of linkage isomeric chloropentarhodanoiridates(III), from which [Ir(NCS)(SCN)₅]^3? has been isolated by ion exchange chromatography on DEAE-cellulose. The X-Ray structure determination on a single crystal of (n-Bu₄N)₃[Ir(NCS)(SCN)₅] (monoclinic, space group P 2₁/a, a = 17.513(5), b = 32.607(5), c = 23.661(5) Å, β = 94.757(5)°, Z = 8) confirms the existance of a heteroleptic hexakis(thiocyanato(N)-thiocyanato(S))iridate(III) with an Ir? N distance of 2.03 Å and Ir? S bond lengths between 2.29 and 2.38 Å. The SCN groups with angles between 166 and 175° are nearly linear with Ir? S? C angles from 99.9 to 109.4°. The Ir? N? C angles of the two crystallographic independent anions are 166 and 174°.     

Ligandenaustauschreaktionen am Bis(1,3-diselenol-2-selon-4,5-diselenolato)-kupferat(II) ([Cu(dsis)2]2−) mit Kupfer(II)-Vier- und Fünfringchelaten geminaler und vicinaler ungesättigter Dichalkogenoliganden. Eine EPR-Untersuchung

Ligand Exchange on Bis(1,3-diselenole-2-selone-4,5-diselenolato)cuprate(II) ([Cu(dsis)₂]^2?) with Cu^II Four and Five Ring Bis-chelates Containing Unsaturated Vicinal and Geminal Dichalcogeno Ligands. An EPR Study Ligand exchange reactions (“chelate metathesis”) of bis(1,3-diselenole-2-selone-4,5-diselenolato)cuprate(II), ([Cu(dsis)₂]^2?, with other Cu^II four- or five-ring chelates of unsaturated dichalcogeno ligands are reported. The small solubility of salts of the title complex in common solvents like acetone or chloroform requires pyridine. Mixed-ligand complexes could be detected for all combinations of two starting complexes studied by means of their g_o and a_o^Cu (EPR) parameters. Due to the coordinating properties of pyridine and electronic reasons commonly used linear dependences of the g value from the composition of the first coordination sphere (“additivity rules”) are not applicable.     

A New Conducting Molecular Solid Based on the Magnetic [Ni(dmf)6] Cation and on [Ni(dsit)2]2 (dsit=1,3-dithiole-2-thione-4,5-diselenolate) Showing an Unprecedented Anion Packing

The synthesis, X-ray structure, magnetic and transport properties of the compound Ni(dmf)₆[Ni(dsit)₂]₂ (dmf=dimethylformamide, dsit=1,3-dithiole-2-thione-4,5-diselenolate) are described. This compound crystallizes in the monoclinic space group P2₁/c, with a=18.709(6), b=22.975(5), c=20.418(5) Å, β=99.31(2)° and Z=6; its structure consists of [Ni(dsit)₂]₂²⁻ dimers and isolated [Ni(dmf)₆]²⁺ cations both centrosymmetric and non-centrosymmetric. The dimers are packed forming chains along the [101] direction with short Se·Se interdimer contacts. Additional interchains S·S contacts render this structure a three-dimensional character, never observed so far in other [Ni(dsit)₂]⁻ salts. This compound exhibits semiconducting behavior with a room temperature conductivity (1 S cm⁻¹) much higher than those reported for other salts of the [Ni(dsit)₂]⁻ anion. Tight-binding band structure calculations were used to analyze the origin of the semiconducting properties of this salt. The magnetic susceptibility shows Curie behavior with C=1.25 emu K mol⁻¹, typical of isolated Ni(II) ions as expected for the octahedrally coordinated [Ni(dmf)₆]²⁺ cations.     

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.     

Zur Kenntnis des Natrium-tetrahydroxoaluminat-chlorids Na2[Al(OH)4]Cl

On the Sodium Tetrahydroxoaluminate Chloride Na₂[Al(OH)₄]Cl The hitherto unknown compound Na₂[Al(OH)₄]Cl was prepared by crystallisation from a NaCl containing sodium aluminate solution. According to the X-ray single crystal investigation (tetragonal, space group P4/nmm, a = 7.541 Å, c = 5.059 Å, Z = 2) the compound represents the first example of a crystalline hydroxoaluminate with monomeric [Al(OH)₄]^? anions. Cl^? shows a quadratic anti prismatic coordination to 4 Na⁺ and over hydrogen bonds to 4 O^2? while Na⁺ is octahedrally coordinated by 4 O^2? and 2 Cl^? (axial). The results of the crystal structure analysis are confirmed by ²⁷Al and ²³Na MAS NMR investigations. Na₂[Al(OH)₄]Cl decomposes at about 200°C without intermediates under formation of β-NaAlO₂ and NaCl.     

Synthese und Charakterisierung von Metallocen-Chelaten heterocyclischer 1,2-Dithiolate

Synthesis and Characterization of Metallocene Chelates of Heterocyclic 1,2-Dithiolates Synthesis and properties of metalocene dithiolene chelates Cp₂ML with metal(IV) ions (M) of group IVA (Ti, Zr, Hf) and of vanadium with L = dmit (1,3-dithiole-2-thione-4,5-dithiolate), dmt (1,2-dithiole-3-thione-4,5-dithiolate), dmid (1,3-dithiole-2-one-4,5-dithiolate) and dmise (1,3-dithiole-2-selone-4,5-dithiolate) are described. The structures of these compounds were discussed using IR-, UV/VIS-, ¹H-NMR-, ¹³C-NMR- and EPR data. The activation parameters of the chelate ring inversion of titanocene dithiolenes (Cp₂TiL) and the x-ray structure of Cp₂Ti(dmid) are given.     

Metallchelate ungesättigter geminaler Dichalcogenoliganden mit gemischten S,Se-Ligatoren Kristall- und Molekülstruktur von Tetra-n-butylammonium-bis(1,1-dicyanoethylen-2,2-thioselenolato)nickelat(II), [(n-C4H9)4N]2[Ni(SSeC?C(CN)2)2]

Metal Chelates of Unsaturated Geminal Dichalcogeno Ligands Containing S as well as Se Ligators. Crystal and Molecular Structure of Tetra-n-butylammonium-bis(1,1-dicyanoethylene-2,2-thioselenolato)nickelate(II), [(n-C₄H₉)₄N]₂[Ni(SSeC? C(CN)₂)₂] Synthesis and properties of chelates of the thioseleno ligands 1,1-dicyanoethylene-2,2-thioselenolate (bis-chelates with Ni²⁺, Pd²⁺, Pt²⁺, Cu²⁺, Au³⁺, Zn²⁺, Cd²⁺, Se²⁺, Te²⁺, UO₂²⁺; tris-chelate mit Cr³⁺, Fe³⁺, Co³⁺, Rh³⁺, In³⁺; 1:1-chelate mit Cu⁺, Au⁺), cyanthioselenocarbimate (bis-chelates with Ni²⁺, Pd²⁺) and 0-β-methoxyethyl-thioselenocarbonate (bis-chelates with Ni²⁺, Pd²⁺, Pt²⁺, Zn²⁺; tris-chelate mit Cr³⁺, Co³⁺, Rh³⁺) are reported. The X-ray crystal structure of [(n-C₄H₉)₄N]₂[Ni(SSeC? C(CN)₂)₂] shows a planar NiS₂Se₂ arrangement. From the space group P2₁/c (a = 14,043(1) Å, b = 8.704(1) Å, c = 20.647(2) Å, β = 108.56(1)°) and Z = 2 follows a trans position of the thioseleno ligands. The same magnitude of the C–S and C–Se distance refers to a hindrance of the equalization of the bonding in the chelate. The structure is compared with those of similar compounds.     

Synthesis and Crystal Structures of Bis(tetraethylammonium)(2-oxo-1,3-dithiole-4,5-dithiolato)zincate(II) and Bis(tetra-n-butylammonium)(2-oxo-1,3-dithiole-4,5-dithiolato)zincate(II)

The title compounds were prepared from 1,3,4,6-tetrathiapentalene-2,5-dione ( 1 ) in one step via the in situ generated intermediate 2-oxo-1,3-dithiole-4,5-dithiolate (dmid; 2 ). The X-ray single crystal structure of (Et₄N)₂[Zn(dmid)₂] ( 3 a ) gave the tetragonal space group P4₃2₁2 with a = b = 13.810(2) Å, c = 16.480(3) Å, and Z = 4. (n-Bu₄N)₂[Zn(dmid)₂] ( 3 b ) gave the triclinic space group P 1 with a = 11.947(4) Å, b = 14.665(5) Å, c = 16.662(8) Å, α = 100.21(3)°, β = 104.46(3)°, γ = 110.73(3)°, and Z = 2.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von cis‐ und trans‐(n‐Bu4N)2[PtF2(ox)2] und (n‐Bu4N)2[PtF4(ox)]

Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of cis‐ and trans‐(n‐Bu₄N)₂[PtF₂(ox)₂] and (n‐Bu₄N)₂[PtF₄(ox)] By treatment of trans‐(n‐Bu₄N)₂[PtCl₂(ox)₂] and (n‐Bu₄N)₂[PtCl₄(ox)] with XeF₂ in propylene carbonate cis‐ and trans‐(n‐Bu₄N)₂[PtF₂(ox)₂] ( 1 , 2 ) and (n‐Bu₄N)₂[PtF₄(ox)] ( 3 ) are formed which have been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The crystal structure of trans(n‐Bu₄N)₂[PtF₂(ox)₂] ( 2 ) (tetragonal, space group P4₂/n, a = 15.5489(9), b = 15.5489(9), c = 17.835(1)Å, Z = 4) und Cs₂[PtF₄(ox)] ( 3 ) (monoclinic, space group C2/m, a = 14.5261(7), b = 6.2719(4), c = 9.6966(9)Å, β = 90.216(8)°, Z = 4) reveal complex anions with nearly D_2h and C_2v point symmetry. The average bond lengths in the symmetrical coordinated axes are Pt—F = 1.93 ( 2 , 3 ) and Pt—O = 1.987 ( 2 ) and in the F^•—Pt—O′‐axes Pt—F^• = 1.957 and Pt—O′ = 1.977Å ( 3 ). The oxalato ligands are nearly planar with a maximum displacement of the ring atoms of 0.05 ( 2 ) und 0.01Å ( 3 ) to the calculated best planes. In the vibrational spectra the symmetric and antisymmetric PtF stretching vibrations are observed at 583 and 586 ( 2 ) and 576 and 568 cm^—1 ( 3 ). The PtF^• modes appear at 565 and 562 ( 1 ) and 560 cm^—1 ( 3 ). The PtO and PtO′ stretching vibrations are coupled with internal modes of the oxalato ligands and appear in the range of 400—800 cm^—1. Based on the molecular parameters of the X‐ray determinations ( 2 , 3 ) and estimated data ( 1 ) the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are f_d(PtF) = 3.55 ( 2 ) and 3.38 ( 3 ), f_d(PtF^•) = 3.23 ( 1 ) and 3.20 ( 3 ), f_d(PtO) = 2.65 ( 1 ) and 2.84 ( 2 ) and f_d(PtO′) = 2.97 ( 1 ) and 3.00 mdyn/Å ( 3 ). Taking into account increments of the trans influence a good agreement between observed and calculated frequencies is achieved. The NMR shifts are δ(¹⁹⁵Pt) = 8485 ( 1 ), 8597 ( 2 ) and 10048 ppm ( 3 ), δ(¹⁹F) = —350 ( 2 ) and —352 ( 3 ) and δ(¹⁹F^•) = —323 ( 1 ) and —326 ppm ( 3 ) with the coupling constants ¹J(PtF) = 1784 ( 2 ) and 1864 ( 3 ) and ¹J(PtF^•) = 1525 ( 1 ) and 1638 Hz ( 3 ).     

Kristallstrukturen,Schwingungsspektren und Normalkoordinatenanalyse von (n‐Bu4N)2[Os(NCS)6] und (n‐Bu4N)3[Os(NCS)6]

Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of ( n ‐Bu₄N)₂[Os(NCS)₆] and ( n ‐Bu₄N)₃[Os(NCS)₆] By tempering the solid mixture of the linkage isomers (n‐Bu₄N)₃[Os(NCS)_n(SCN)_6–n] n = 0–5 for a longer time at temperatures increasing from 60 to 140 °C the homoleptic (n‐Bu₄N)₃[Os(NCS)₆] is formed, which on oxidation with (NH₄)₂[Ce(NO₃)₆] in acetone yields the corresponding Os^IV complex (n‐Bu₄N)₂[Os(NCS)₆]. X‐ray structure determinations on single crystals of (n‐Bu₄N)₂[Os(NCS)₆] (1) (triclinic, space group P 1, a = 12.596(5), b = 12.666(5), c = 16.026(5) Å, α = 88.063(5), β = 80.439(5), γ = 88.637(5)°, Z = 2) and (n‐Bu₄N)₃[Os(NCS)₆] ( 2 ) (cubic, space group Pa 3, a = 24.349(4) Å, Z = 8) have been performed. The nearly linear thiocyanate groups are coordinated with Os–N–C angles of 172.3–177.7°. Based on the molecular parameters of the X‐ray determinations the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constant f_d(OsN) is 2.3 ( 1 ) and 2.10 mdyn/Å ( 2 ).     

Neue Oxonium-Bromochalkogenate(IV) — Darstellung,Struktur und Eigenschaften von [H3O][TeBr5] · 3C4H8O2 und [H3O]2[SeBr6]

New Oxonium Bromochalcogenates(IV) — Synthesis, Structure, and Properties of [H₃O][TeBr₅] · 3 C₄H₈O₂ and [H₃O]₂[SeBr₆] Dark red crystals of the composition [H₃O][TeBr₅] · 3 C₄H₈O₂ ( 1 ) were isolated from a saturated solution of TeBr₄ in 1,4-dioxane containing a small amount of water. In this compound (space group P2₁/m, a = 8.922(4) Å, b = 13.204(7) Å, c = 9.853(5) Å, β = 91.82(4)° at 150 K) a square pyramidal [TeBr₅]^? anion has been isolated for the first time. The coordination sphere of the anion is completed to a distorted octahedron by weak interaction with a dioxane molecule of the cationic system. The [H₃O]⁺ cations are connected to chains by dioxane molecules. At room temperature the compound is stable only in its mother liquor. Crystalline [H₃O]₂[SeBr₆] ( 2 ) (space group Fm3m, a = 10.421(1) Å at 170 K) is a bromoselenous acid of high symmetry. The [H₃O]⁺ ion is only weakly coordinated by Br atoms of the anion. The anions are isolated octahedral [SeBr₆]^2? units. The structure is isotypic to the K₂[PtCl₆] structure. Despite being a halogenochalcogen(IV) acid, 2 exhibits a remarkable thermal stability. Both oxonium compounds were characterized by single-crystal X-ray structure analyses. Vibrational spectra of 2 are reported.     

Synthese und Struktur eines Molybdän–Gadolinium-Heterometall-Komplexes Die Struktur von [Li(thf)4]2[Cp2MoSGdBr4(thf)]2

Synthesis and structure of a Molybdenum–Gadolinium Heterometallic Complex. The Structure of [Li(thf)₄]₂[Cp₂MoSGdBr₄(thf)]₂ [Cp₂MoHLi] reacts in THF with S and GdBr₃ to yield the tetranuclear heterobimetallic complex [Li(thf)₄]₂[Cp₂MoSGdBr₄(thf)]₂. The bonding situation and the structure of this compound were characterized by X-ray structure analysis (space group P1 (No. 2), Z = 1, a = 10.845(2) Å, b = 12.166(2) Å, c = 15.881(2) Å, α = 101.74(2)°, β = 97.62(2)°, γ = 103.97(2)°). Each S atom of the central Mo₂S₂-ring is coordinated by a GdBr₄(thf) fragment. Additionally each Mo atom is connected to two Cp ligands. This leads to a tetrahedral coordination of the Mo atoms and a octahedral coordination of the Gd ions.     

Komplexchemie P-reicher Phosphane und Silylphosphane. XI [1]. Bildung,Reaktionen und Strukturen von Chromcarbonylkomplexen aus Reaktionen von Li(THF)2[η2-(tBu2P)2P] mit Cr(CO)5 · THF und Cr(CO)4 · NBD

Transition Metal Complexes of P-rich Phosphanes and Silylphosphanes. XI. Formation, Reactions, and Structures of Chromium Carbonyl Complexes from Reactions of Li(THF)₂[η₂-(^tBu₂P)₂P] with Cr(CO)₅ · THF and Cr(CO)₄ · NBD Reactions of Li(THF)₂[η²-(^tBu₂P)₂P] 1 with Cr(CO)₅ · THF yield Li(THF)₂Et₂O[Cr(CO)₄{η²-(^tBu₂P)₂P}η¹-Cr(CO)₅] 2 and the compounds [Cr(CO)₄{η²-(^tBu₂P)₂PH}] 3 , [Cr(CO)₅{η¹-(^tBu₂P)₂PH}] 4 , (^tBu₂P)₂PH 5 and ^tBu₂PH · Cr(CO)₅ 6 . The formation of 3, 4, 5 and 6 is due to byproducts coming from the synthesis of 1. 2 reacts with CH₃COOH under formation of 3 . After addition of 12-crown-4 1 with NBD · Cr(CO)₄ in THF forms Li(12-crown-4)₂[Cr(CO)₄-{η²-(^tBu₂P)₂P}] 7 (yellow crystals). 7 reacts with CH₃COOH to 3 – which regenerates 7 with LiBu – with Cr(CO)₅THF to compound 2 , with NBD · Cr(CO)₄ in THF to 2 and 3 (ratio 1 : 1). With EtBr, 7 forms [Cr(CO)₄{η²-(^tBu₂P)₂PEt}] 8 , and [Cr(CO)₄{η²-(^tBu₂P)₂PBr}] 9 with BrCH₂? CH₂Br. The compounds were characterized by means of ¹H, ¹³C, ³¹P, ⁷Li NMR spectroscopy, IR spectroscopy, elementary analysis, mass spectra, and 2, 3 and 4 additionally by means of X-ray diffraction analysis. 2 crystallizes in the space group P1 with 2 formula units in the elementary cell; a = 10.137(9), b = 15.295(12), c = 15.897(14) Å; α = 101.82(7), β = 91.65(7), γ = 98.99(7)°; 3 crystallizes in the space group P2_t/n with 4 molecules in the elementary unit; a = 11.914(6), b = 15.217(10), c = 14.534(10) Å; α = 90, β = 103.56(5), γ = 90°. 4 : space group P1 with 2 molecules in the elementary unit; a = 8.844(4), b = 12.291(6), c = 14.411(7) Å, α = 66.55(2), β = 89.27(2), γ = 71.44(2)°.     

Kristallstruktur von (Me4N)3[Ir(SCN)6], Schwingungsspektrum und Normalkoordinatenanalyse

Crystal Structure of (Me₄N)₃[Ir(SCN)₆], Vibrational Spectra and Normal Coordinate Analysis From a mixture of the linkage isomers [Ir(NCS)_n(SCN)_6–n]^3–, n = 0–2, pure [Ir(SCN)₆]^3– has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on a single crystal of (Me₄N)₃[Ir(SCN)₆] (trigonal, space group R3, a = 14.838(2), c = 23.827(1) Å, Z = 6) reveals the presence of two crystallographically independent complex anions which C_3i symmetry correlates with the cation/anion ratio 3 : 1. The thiocyanate ligands are exclusively S-coordinated with the average Ir–S distance of 2.384 Å and the Ir–S–C angle of 106.4°. The torsion angles S–Ir–S–C are 17.5 and 42.1°. The IR and Raman spectra of the (n-Bu₄N) salt are assigned by normal coordinate analysis based on the molecular parameters of the X-ray determination. The valence force constant f_d(IrS) is 1.57 mdyn/Å.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von (n‐Bu4N)2[PtX4(ox)], X = Cl,BR

Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of (n‐Bu₄N)₂[PtX₄(ox)], X = Cl, Br By oxidation of (n‐Bu₄N)₂[PtX₂(ox)], X = Cl, Br, with Cl₂ or Br₂ in dichloromethane (n‐Bu₄N)₂[PtCl₄(ox)] ( 1 ) and (n‐Bu₄N)₂[PtBr₄(ox)] ( 2 ) are formed. The crystal structure of [(C₅H₅N)₂CH₂][PtCl₄(ox)] (monoclinic, space group C2/m, a = 15.562(1), b = 13.779(1), c = 10.168(1)Å, ß = 128.099(9)°, Z = 4) reveals complex anions with nearly C_2v point symmetry. The bond lengths in the Cl′‐Pt‐O^˙ axes are Pt‐Cl′ = 2.287 and Pt‐O^˙ = 2.048 and in the Cl‐Pt‐Cl axis Pt‐Cl = 2.314Å. The oxalato ligand is nearly plane with an O‐C‐C‐O torsion angle of 0.5°. In the vibrational spectra the PtX stretching vibrations are observed at 328 and 353 ( 1 ) and 201 and 212 cm^—1 ( 2 ). The PtX′ modes appear at 360 and 343 ( 1 ) and 227 and 238 cm^—1 ( 2 ). The PtO^˙ stretching vibrations are coupled with internal modes of the oxalato ligands and appear in the range of 400—800 cm^—1. Based on the molecular parameters of the X‐ray determination ( 1 ) and estimated data ( 2 ) the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are f_d(PtCl) = 2.08, f_d(PtCl′) = 2.29, f_d(PtBr) = 1.56, f_d(PtBr′) = 2.02 and f_d(PtO^˙) = 2.46 ( 1 ) and 2.35 mdyn/Å ( 2 ). Taking into account increments of the trans influence a good agreement between observed and calculated frequencies is achieved. The NMR shifts are δ(¹⁹⁵Pt) = 5623.0 ( 1 ) and 4536.1 ( 2 ).