Neue ternäre Phosphide und Arsenide mit einem Metall : Nichtmetall‐Verhältnis im Bereich von 2 : 1

New Ternary Phosphides and Arsenides with a Metal : Non‐Metal Ratio in the Range of 2 : 1 Six new compounds were prepared by heating mixtures of the elements or by reaction of them in a tin(lead) flux. They were investigated by single crystal X‐ray methods. Sc₂Ni₁₂P₇ (a = 9.013(1), c = 3.590(1) Å) crystallizes in the Zr₂Fe₁₂P₇ type structure (P6; Z = 1), which is basically built up likewise by Eu₂Pd₁₂As₇ (a = 10.040(1), c = 4.100(1) Å) and Sr₂Rh₁₂P₇ (a = 9.626(1), c = 3.844(1) Å), but one of seven non‐metal atoms has a somewhat modified environment and is disordered along [001]. Therefore their crystal structure corresponds to the Ho₂Rh₁₂As₇ type structure (P6₃/m; Z = 1). Ca₂Ni₇P₄ (a = 3.703(1), b = 9.209(1), c = 10.378(1) Å) forms the Nd₂Ni₇P₄ type structure (Pmn2₁; Z = 2), whereas the atomic arrangements of Ca₄Rh₁₃As₉ (a = 3.903(2), b = 11.221(1), c = 19.411(4) Å) and Sm₄Rh₁₃As₉ (a = 3.913(2), b = 11.242(6), c = 19.440(6) Å) correspond basically to the Ho₄Ir₁₃Ge₉ type structure (Pmmn; Z = 2), but the disorder of Rh8 required the occupation of splitting positions. The transition metals have three, four or five neighbouring atoms of phosphorus or arsenic and form together with them three‐dimensional covalent frameworks, of which holes are occupied by the atoms of the electropositive metal. Most of the polyhedra around the P and As atoms respectively consist of trigonal prisms of metal atoms with additional metal atoms capping the rectangular faces of the prisms. This environment ist characteristic for ternary phosphides and arsenides with a metal : non‐metal ratio in the range of 2 : 1.     

Phosphaniminato‐Komplexe des Hafniums. Die Kristallstrukturen von [Hf(NPPh3)4] · 3 THF und [Hf(NPPh3)2Cl2(HNPPh3)2]

Phosphoraneiminato Complexes of Hafnium. Crystal Structures of [Hf(NPPh₃)₄] · 3 THF and [Hf(NPPh₃)₂Cl₂(HNPPh₃)₂] The phosphoraneiminato complexes [Hf(NPPh₃)₄] · 3 THF ( 1 · 3 THF) and [Hf(NPPh₃)₂Cl₂(HNPPh₃)₂] ( 2 ) have been prepared as colourless, moisture sensitive single crystals by reactions of hafnium tetrachloride with [CsNPPh₃]₄ · 2 toluene in tetrahydrofurane solutions by application of different ratios of the educts. Both complexes are characterized by IR spectroscopy and X‐ray crystal structure determinations. 1 · 3 THF: space group P 1, Z = 4, lattice dimensions at 193 K: a = 2007.6(1); b = 2064.2(1); c = 2115.9(1) pm; α = 109.193(4)°; β = 111.285(4)°; γ = 96.879(4)°; R₁ = 0.0506. 1 forms monomeric molecules with tetrahedral coordination of the nitrogen‐atoms of the (NPPh₃^–)‐groups towards the Hafnium atom. The HfN distances of 200.9 pm in average correspond with double bonds. 2 : space group P 1, Z = 4, lattice dimensions at 193 K: a = 1444.0(1); b = 1928.1(1); c = 2455.8(2) pm; α = 67.273(8)°; β = 87.445(8)°; γ = 87.082(8)°; R₁ = 0.0312. 2 has a monomeric molecular structure with octahedral coordination of the hafnium atom. The chlorine atoms are in trans position to one another, whereas the nitrogen atoms of the phosphoraneiminato groups (NPPh₃^–) are in trans position towards the nitrogen atoms ot the phosphorane imine molecules (HNPPh₃). The HfN bond lengths of the (NPPh₃^–) groups of 199.7 pm in average correspond with double bonds, whereas the HfN distances of the HNPPh₃ molecules with bond lengths of 230.2 pm in average are of donor‐acceptor type.     

Synthese und Struktur von RbHfF5, Rb2Zr3F12O und Rb2Hf3F12O — zwei Oxidfluoride mit zentraler trigonal‐planarer [M3O]‐Gruppe

Synthesis and Structure of RbHfF₅, Rb₂Zr₃F₁₂O and Rb₂Hf₃F₁₂O — two Oxydefluorides with Central Trigonal‐plane [M₃O] Group Colorless RbHfF₅ crystallizes isotypic with (NH₄)ZrF₅ and TlHfF₅ monoclinic, space group P2₁/c ‐ C_2h (No. 14) with a = 776.6, b = 789.6, c = 789.8 pm, and β = 120.52°. Also colorless Rb₂Zr₃F₁₂O crystallizes trigonal, space group R3¯m — D₃d (No. 166), with a = 771.9 and c = 2963.0 pm, isotypic is Rb₂Hf₃F₁₂O with a = 769.2 pm and c = 2986.1 pm. Both compounds are isotypic with Tl₂Zr₃F₁₂O.     

KCuMIVF7 (MIV = Zr4+, Hf 4+), ein neuer Strukturtyp

KCuM^IVF₇ (M^IV = Zr⁴⁺, Hf ⁴⁺) a New Type of Structure KCuZrF₆ (colourless, orthorhombic, Cmcm – D (No. 63); a = 829,6 pm, b = 1276,5 pm, c = 1011,6 pm, Z = 8) and KCuHfF₇ (colourless, orthorhombic, Cmcm – D (Nr. 63); a = 829,6 pm, b = 1276,5 pm, c = 1011,6 pm, Z = 8) could be prepared by heating up in a goldtube at 700 °C for 3 weeks a mixture of KF, CuF₂, and ZrF₄ or HfF₄, respectively. Both compounds crystallize isotypic in a previous unknown structure.     

Synthese und Struktur von Ag7M6F31 (M = Zr,Hf, Ce)

Synthesis and Structure of Ag₇M₆F₃₁ (M = Zr, Hf, Ce) Colorless single crystals of Ag₇Zr₆F₃₁ have been obtainend by heating up a mixture of AgF and ZrF₄ in a closed goldtube (T = 450 °C, t ∼ 2 d). The compound crystallizes trigonal, space group R3‐C (No. 148) with a = 1400,9(3) pm, c = 979,0(2) pm, Z = 3. Also prepared were the isotypic compounds Ag₇Hf₆F₃₁ with a = 1393,8(2) pm, c = 978,7(2) pm, and Ag₇Ce₆F₃₁ with a = 1469,8(1) pm, c = 998,5(1) pm.     

Zwei neue Iodopalladate mit gleicher Summenformel: Rb2PdI4 · I2 – ein neuer Strukturtyp mit eingelagerten I2‐Molekülen – und Rb2PdI6

Two New Iodopalladates with Identical Chemical Formula: Rb₂PdI₄ · I₂ – a New Structure Type with Insertion of I₂ Molecules – and Rb₂PdI₆ Rb₂PdI₄ · I₂ is the first rubidium iodopalladate(II) which could be prepared. Despite showing the same formula type, the compound is not isotypic to Cs₂PdI₄ · I₂. The crystal structure of Rb₂PdI₄ · I₂ was explored by X‐ray crystal structure analysis. Rb₂PdI₄ · I₂ shows orthorhombic symmetry, space group Pnma (No. 62) with lattice parameters a = 7.982(1) Å, b = 12.267(1) Å, c = 14.599(1) Å, Z = 4. Palladium is coordinated by four iodine atoms building the typical square‐planar coordination. Further iodine is inserted as I₂ molecules. Another compound with the same empirical formula but octahedrally coordinated Pd^IV – Rb₂PdI₆ – could be obtained microcrystallinic in connection with Rb₂PdI₄ · I₂.     

Ternäre Alkalimetall‐Übergangsmetall‐Acetylide der Zusammensetzung A2MC2 mit A = Rb,Cs und M = Pd,Pt

Ternary Alkali Metal Transition Metal Acetylides A₂MC₂ with A = Rb, Cs, and M = Pd, Pt By the reaction of Rb₂C₂ and Cs₂C₂ with palladium or platinum powder in sealed glass ampoules at 653 K ternary acetylides A₂MC₂ (A = Rb, Cs; M = Pd, Pt) were obtained. Their crystal structures were solved and refined by means of X‐ray powder investigations (Na₂PdC₂ structure type, P 3 m1, Z = 1). The crystal structures are characterised by [M(C₂)_2/2^2–] chains separated by the alkali metals. Raman spectroscopic investigations revealed wave numbers of the C–C stretching vibrations between 1833 and 1842 cm^–1, which are in good agreement with the results of the analogous sodium and potassium compounds.     

1,4-Diaza-1,3-dien-Verbindungen elektronenarmer Übergangsmetalle σ-Donor- und π-Akzeptor-Komplexe des Zirconiums und Hafniums mit perphenylsubstituierten DAD-Liganden – ein Strukturvergleich

1,4-Diaza-1,3-diene Compounds of Early Transition Metals. σ-Donor and π-Acceptor Complexes of Zirconium and Hafnium with perphenyl-substituted DAD Ligands – a Comparison of Structures Reaction of 1,4- D i a za-1,3- d ienes (DAD) with the Lewis-acid ZrCl₄ affords σ-donor-complexes of composition ZrCl₄ · DAD. The X-ray analysis of the ( 2c ) (space group P1 , triclinic; a = 11.339(2), b = 11.845(2), c = 12.415(3) Å, α = 107.94(2), β = 107.26(2), γ = 104.73(2)°, Z = 2, R1 = 0.0266) shows that both N-atoms of the s-cis-configurated DAD-ligand occupy two corners of a distorted octahedron. There is only slight difference between the C?N bond lengths of the coordinated and noncoordinated ligand. In the homoleptic DAD-complexes of the type M(DAD)₃ [M = Zr ( 4b ), Hf ( 5b ), R = C₆H₄-4-Me] the DAD-ligands more act as π-acceptor ligands. X-ray analysis shows that the complexes [M = Zr ( 4b ), Hf ( 5b ), R = C₆H₄-4-Me] have the identical structure motive and crystallize in the triclinic space group P1 ( 4b : a = 14.904(1), b = 15.451(2), c = 19.584(4) Å, α = 112.08(1), β = 94.36(1), γ = 97.60(1)°, Z = 2, R1 = 0.0911; 5b a = 14.798(2), b = 18.226(2), c = 22.902(2) Å, α = 71.62(1), β = 72.38(1), γ = 87.27(1)°, Z = 2, R1 = 0.0644). The six N-atoms form a distorted octahedron in both complexes. The planarity of the five-membered rings and the almost similar C?N and C? C bond lengths are typical of the π-acceptor function of the diazadienes in 4b and 5b . The steric hindrance in 4b und 5b results in a dynamical behavior and a asymmetrical distortion at low temperatures as was observed by n.m.r.     

Ternäre Nickelphosphide und -arsenide mit einem Metall: Nichtmetall-Verhältnis von 2:1

Ternary Phosphides and Arsenides of Nickel with a Metal: Non-Metal Ratio of 2:1 Several new ternary phosphides and arsenides of nickel were prepared by reaction of the elements. SrNi₅P₃, SrNi₅As₃, and EuNi₅As₃ crystallize in the LaCo₅P₃ structure with the following lattice constants [Å]: BaNi₉P₅ (a = 6.534(1) Å, c = 10.847(2) Å) and BaNi₉As₅ (a = 6.760(1) Å, c = 11.226(2) Å) crystallize in a new type of structure (P6₃/mmc, Z = 2). The characteristic polyhedra are trigonal Ni-antiprisms centered by P or As atoms and trigonal Ni-prisms with vacant centres and sides capped by non-metal atoms. U₂Ni₁₂P₇ (a = 9.077(2) Å, c = 3.694(1) Å) has a Zr₂Fe₁₂P₇ structure (P6 , Z = 1).     

Darstellung und Strukturen von Mg‐Komplexen mit α, ω‐Dicarboxylato‐Liganden (Dicarboxylat = Succinat,Glutarat und Suberat)

Syntheses and Structures of Magnesium Complexes with α, ω‐Dicarboxylato Ligands; Dicarboxylate = Succinate, Glutarate, and Suberate Crystals of (Tetraaqua)(succinato)magnesium ( 1 ), (Tetraaqua)(glutarato)magnesium ( 2 ) und (Triaqua)(suberato)magnesium ( 3 ) were obtained by layering an aqueous solution of the respective sodium salt with a solution of MgCl₂ in isopropanol. In 1 a chain structure is realized. Mg(H₂O)₄ units are bridged in trans orientation by α, ω‐bonded succinate groups. 2 contains also chains. Glutarato groups are bonded in a cis fashion to Mg(H₂O)₄ units. They form bridges by using their two α O atoms. 3 represents a layer structure. The basic structural motives are α, α, ω‐bonded suberate, and fac‐Mg(H₂O)₃ units. All three structures contain efficient H bridging systems. The connection between the symmetry of the polymeric groups (chains or layer) and the symmetry of the underlying space groups is discussed. 1 : Space group P2₁/c, Z = 4, lattice constants at 20 °C: a = 7.441(2), b = 14.827(2), c = 7.771(2) Å; β = 99.77(3)°, R1 = 0.052. 2 : Space group C2/c, Z = 8, lattice constants at 20 °C: a = 12.867(2), b = 7.109(1), c = 21.683(3) Å; β = 107.33(2)°; R₁ = 0.032. 3 : Space group P2₁/a, Z = 4, lattice constants at 20 °C: a = 9.174(2), b = 8.071(2), c = 15.960(3) Å; β = 104.29(2)°; R₁ = 0.052.     

Na2ZrS3: Ein ternäres Sulfid des Zirconiums mit aufgefüllter AlCl3‐Struktur

Na₂ZrS₃: A Ternary Zirconium Sulfide with Stuffed AlCl₃‐type Structure Dark green, plate‐like single crystals of Na₂ZrS₃ (monoclinic, C2/m; a = 664.69(6), b = 1152.5(1), c = 695.48(7) pm, β = 108.78(1)°; Z = 4) are obtained along with pale yellow platelets of NaZr₂N₂SCl (trigonal, R3m; a = 363.56(3), c = 2951.2(4) pm; Z = 3) upon oxidation of zirconium metal with sulfur and sodium azide (NaN₃) in the presence of fluxing NaCl (molar ratio 7:6:2:3) in evacuated silica tubes at 850°C within three weeks. The crystal structure is best described as stuffed AlCl₃ type with all cations (Na⁺ and Zr⁴⁺) in octahedral coordination of the S^2– anions, which build up a cubic closest packed host lattice. The internuclear metal sulfur distances range from 276 to 296 pm for all three crystallographically different Na⁺ cations, and from 258 to 260 pm for Zr⁴⁺.     

Darstellung und Struktur der Komplexverbindungen trans‐[CoIII(py)4F2][H2F3] und [Pd(py)4]F2 · 1,5 HF · 2 H2O

Synthesis and Crystal Structures of the Complexes trans ‐[Co^III(py)₄F₂][H₂F₃] and [Pd(py)₄]F₂ · 1.5 HF · 2 H₂O The cobalt complex trans‐[Co(III)(py)₄F₂][H₂F₃] ( 1 ) has been prepared by electrochemical oxidation of CoF₂ in a pyridine/HF mixture and the palladium complex [Pd(py)₄]F₂ · 1.5 HF · 2 H₂O ( 2 ) has been obtained via halogen exchange between Pd(py)₂Cl₂ and AgF₂ in pyridine. 1 and 2 crystallize in the space group C2/c with a = 27.928(14), b = 9.019(3), c = 18.335(8) Å, β = 113.41(3)° for 1 and a = 28.183(9), b = 9.399(3), c = 17.397(6) Å, β = 104.66(3)° for 2 , respectively. Concerning the shape and location of the M(py)₄ fragments 1 and 2 are isostructural. The metal atoms occupy special positions in their unit cells with the result that four complex atoms have C₂ symmetry and four complex cations have C_i symmetry giving a total of Z = 8. In 1 two F^– ions complete an octahedral coordination around the Co atoms (Co–F 1.820(2) to 1.834(3) Å). In 2 the shortest Pd–F distance is 3.031(2) Å. This precludes the existence of Pd–F bonds. In 1 one can identify H₂F₃^– groups. In 2 there are larger aggregates, consisting of F^–, HF, and H₂O subunits, connected by H‐bridges. In spite of these differences, both complexes belong to the same type of structure, which may be of a common type M^x+(py)₄F_x · y HF · z H₂O.     

Darstellung,Eigenschaften und Kristallstruktur von RuSn6[(Al1/3–xSi3x/4)O4]2 (0 ≤ x ≤ 1/3) – einem Oxid mit isolierten RuSn6‐Oktaedern

Preparation, Properties, and Crystal Structure of RuSn₆[(Al_1/3–xSi_3x/4)O₄]₂ (0 ≤ x ≤ 1/3) – an Oxide with isolated RuSn₆ Octahedra RuSn₆[(Al_1/3–xSi_3x/4)O₄]₂ is obtained by the solid state reaction of RuO₂, SnO₂, Sn, and Si in an Al₂O₃‐crucible at 1273 to 1373 K. The compound is cubic with the space group Fm 3 m (a = 9.941(1) Å, Z = 4, R₁ = 0.0277, wR₂ = 0.0619), a semiconductor and stable in air. Results of Mößbauer measurements as well as bond length‐bond strength calculations justify the ionic formulation Ru²⁺Sn₆²⁺[(Al_1/3–x³⁺Si_3x/4⁴⁺)O₄^2–]₂. The central motif of the crystal structure are separated RuSn₆‐octahedrea. These are interconnected by oxygen atoms, arranged tetrahedrely above the surfaces of the RuSn₆‐octahedrea and partialy filled with Al and Si, respectively. Because of these features the compound can be considered as a variant of the crystal structure type of pentlandite.     

Phosphaniminato‐Komplexe des Zirconiums: Die Kristallstrukturen von [ZrCl3(NPPh3)(HNPPh3)2] und [ZrCl2(NPPh3)2(HNPPh3)2]

Phosphoraneiminato Complexes of Zirconium: Crystal Structures of [ZrCl₃(NPPh₃)(HNPPh₃)₂] and [ZrCl₂(NPPh₃)₂(HNPPh₃)₂] The phosphoraneiminato complexes [ZrCl₃(NPPh₃)(HNPPh₃)₂] ( 1 ) and [ZrCl₂(NPPh₃)₂(HNPPh₃)₂] ( 2 ) have been obtained by reaction of [ZrCl₄(THF)₂] with [CsNPPh₃]₄ in THF solution to give colourless moisture sensitive crystals which are characterized by X‐ray structure determinations. [ZrCl₃(NPPh₃)(HNPPh₃)₂] ( 1 ): Space group P 1, Z = 2, lattice dimensions at 193 K: a = 1209.4(2); b = 1480.8(2); c = 1814.2(2) pm; α = 71.203(13)°, β = 71.216(13)°, γ = 74.401(13)°; R = 0.0476. The zirconium atom of 1 is oktahedrally coordinated by the three chlorine atoms in meridional arrangement and by the three nitrogen atoms of the (NPPh₃^–) ligand and of the two phosphane imine molecules HNPPh₃. The ZrN bond distance of the (NPPh₃^–) group (193.5 pm) corresponds with a double bond. [ZrCl₂(NPPh₃)₂(HNPPh₃)₂] ( 2 ): Space group P 1, Z = 4, lattice dimensions at 193 K: a = 1447.6(2); b = 1925.7(2), c = 2457.0(2) pm; α = 67.317(12)°, β = 87.376(12)°, γ = 87.103(13)°; R = 0.0408. The zirconium atom in 2 is octahedrally coordinated by the two chlorine atoms in trans position, and by the nitrogen atoms of the two (NPPh₃^–) groups as well as by the two HNPPh₃ molecules. The ZrN distance of the (NPPh₃^–) ligands (198.9 and 202.0 pm) suggest some π‐interaction between the zirconium and the nitrogen atoms.     

Carbonat‐Hydrate der schweren Alkalimetalle: Darstellung und Struktur von Rb2CO3 · 1,5 H2O und Cs2CO3 · 3 H2O

Carbonate Hydrates of the Heavy Alkali Metals: Preparation and Structure of Rb₂CO₃ · 1.5 H₂O und Cs₂CO₃ · 3 H₂O Rb₂CO₃ · 1.5 H₂O and Cs₂CO₃ · 3 H₂O were prepared from aqueous solution and by means of the reaction of dialkylcarbonates with RbOH and CsOH resp. in hydrous alcoholes. Based on four‐circle diffractometer data, the crystal structures were determined (Rb₂CO₃ · 1.5 H₂O: C2/c (no. 15), Z = 8, a = 1237.7(2) pm, b = 1385.94(7) pm, c = 747.7(4) pm, β = 120.133(8)°, V_EZ = 1109.3(6) · 10⁶ pm³; Cs₂CO₃ · 3 H₂O: P2/c (no. 13), Z = 2, a = 654.5(2) pm, b = 679.06(6) pm, c = 886.4(2) pm, β = 90.708(14)°, V_EZ = 393.9(2) · 10⁶ pm³). Rb₂CO₃ · 1.5 H₂O is isostructural with K₂CO₃ · 1.5 H₂O. In case of Cs₂CO₃ · 3 H₂O no comparable structure is known. Both structures show [(CO₃^2–)(H₂O)]‐chains, being connected via additional H₂O forming columns (Rb₂CO₃ · 1.5 H₂O) and layers (Cs₂CO₃ · 3 H₂O), respectively.     

Darstellung und Eigenschaften von Tetra(n-butyl)ammonium-cis-trifluorophthalocyaninato(2–)zirconat(IV) und -hafnat(IV); Kristallstruktur von (nBu4N)cis[Hf(F)3pc2–]

Preparation and Properties of Tetra(n-butyl)ammonium cis -Trifluorophthalocyaninato(2–)zirconate(IV) and -hafnate(IV); Crystal Structure of (ⁿBu₄N) ^cis [Hf(F)₃pc^2–] cis-Dichlorophthalocyaninato(2–)metal(IV) of zirconium and hafnium reacts with excess tetra(n-butyl)-ammoniumfluoride trihydrate to yield tetra(n-butyl)-ammonium cis-trifluorophthalocyaninato(2–)metalate(IV), (ⁿBu₄N)^cis[M(F)₃pc^2–] (M = Zr, Hf). (ⁿBu₄N)^cis[Hf(F)₃pc^2–] crystallizes in the monoclinic space group P2₁/n (# 14) with cell parameters a = 13.517(1) Å, b = 13.856(1) Å, c = 23.384(2) Å, α = 92.67(1)°, Z = 4. The Hf atom is in a ”︁square base-trigonal cap”︁”︁ polyhedron, coordinating three fluorine atoms and four isoindole nitrogen atoms (N_iso). The Hf atom is sandwiched between the (N_iso)₄ and F₃ planes (d(Hf–Ct_N) = 1.218(3) Å; d(Hf–Ct_F) = 1.229(3) Å; Ct_N/F: centre of the (N_iso)₄, respectively F₃ plane). The average Hf–N_iso and Hf–F distances are 2.298 and 1.964 Å, respectively, the average F–Hf–F angle is 84.9°. The pc^2– ligand is concavely distorted. The optical spectra show the typical metal independent π-π* transitions of the pc^2– ligand at c. 14700 and 29000 cm^–1. In the FIR/MIR spectra vibrations of the MF₃ skeleton are detected at 545, 489, 274 cm^–1 (M = Zr) and 536, 484, 263 cm^–1 (M = Hf), respectively.     

Binäre Lanthan‐Stannide mit Sn:La‐Verhältnissen nahe 1:1 – Synthesen,Kristallstrukturen, Chemische Bindung

Four binary lanthanum stannides close to the 1:1 ratio of Sn:La were synthesized from mixtures of the elements. The structures of the compounds have been determined by means of single‐crystal X‐ray data. The low temperature (α) form of LaSn (CrB‐type, orthorhombic, space group Cmcm, a = 476.33(6), b = 1191.1(2), c = 440.89(6) pm, Z = 4, R1 = 0.0247), crystallizes with the CrB‐type. The structure exhibits planar tin zigzag chains with a Sn–Sn bond length of 299.1 pm. In contrast to the electron precise Zintl compounds of the alkaline earth elements, additional La–Sn bonding contributions become apparent from the results of band structure calculations. In the somewhat tin‐richer region, the new compound La₃Sn₄ (orthorhombic, space group Cmcm, a = 451.45(4), b = 1190.44(9), c = 1583.8(2) pm, Z = 4, R1 = 0.0674), crystallizing with the Er₃Ge₄ structure type, exhibits Sn₃ segments of the zigzag chains of α‐LaSn together with a further Sn atom in a square planar Sn coordination with increased Sn–Sn bond lengths. In the Lanthanum‐richer region, La₁₁Sn₁₀ (tetragonal, space group I4/mmm, a = 1208.98(5), c = 1816.60(9) pm, Z = 4, R1 = 0.0325) forms the undistorted tetragonal Ho₁₁Ge₁₀ structure type. Its structure, which contains isolated Sn atoms, [Sn₂] dumbbells and planar [Sn₄] rings is related to the high temperature (β) form of LaSn. The structure of β‐LaSn (space group Cmmm, a = 1766.97(6), b = 1768.28(5), c = 1194.32(3) pm, Z = 60, R1 = 0.0453), which forms a singular structure type, can be derived from that of La₁₁Sn₁₀ by the removal of thin slabs. Due to the different stacking of the remaining layers, planar [Sn₄] chain segments and linear [Sn–Sn–Sn] anions are formed as additional structural elements. The chemical bonding (Sn–Sn covalent bonding, Sn–La contributions) is discussed on the basis of the simple Zintl concept and the results of FP‐LAPW calculations (density of states, band structure, valence electron densities and electron localization function).     

Kristallstruktur,Schwingungsspektren und Normalkoordinatenanalyse von (n‐Bu4N)2[{Ru(NO)ClI2}2(μ‐I2)] · 2 I2

Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of ( n ‐Bu₄N)₂[{Ru(NO)ClI₂}₂(μ‐I₂)] · 2 I₂ By treatment of (n‐Bu₄N)₂[Ru(NO)I₅] with (n‐Bu₄N)Cl in dichloromethane (n‐Bu₄N)₂[{Ru(NO)ClI₂}₂(μ‐I₂)] is formed. The X‐Ray structure determination on a single crystal of (n‐Bu₄N)₂[{Ru(NO)ClI₂}₂(μ‐I₂)] · 2 I₂ (monoclinic, space group I 2/a, a = 20.446(6), b = 11.482(8), c = 27.225(3) Å, β = 107.51(4)°, Z = 4) reveals a dinuclear iodine bridged structure, in which the chlorine atoms are trans positioned to the nitrosyl groups. The low temperature IR and Raman spectra have been recorded of (n‐Bu₄N)₂[{Ru(NO)ClI₂}₂(μ‐I₂)] · 2 I₂ and are assigned by normal coordinate analysis. A good agreement between observed and calculated frequencies is achieved. The valence force constants are f_d(NO) = 14.08, f_d(RuN) = 5.58, f_d(RuCl) = 1.52, f_d(RuI_t) = 0.90 and f_d(RuI_b) = 0.76 mdyn/Å.     

Gemischte Sandwichkomplexe der 4 f‐Elemente: Enantiomerenreine Cyclooctatetraenyl‐Cyclopentadienyl‐Komplexe des Samariums und Lutetiums mit donorfunktionalisierten Cyclopentadienylliganden

Organometallic Compounds of the Lanthanides. 139 Mixed Sandwich Complexes of the 4 f Elements: Enantiomerically Pure Cyclooctatetraenyl Cyclopentadienyl Complexes of Samarium and Lutetium with Donor‐Functionalized Cyclopentadienyl Ligands The reactions of [K{(S)‐C₅H₄CH₂CH(Me)OMe}], [K{(S)‐C₅H₄CH₂CH(Me)NMe₂}] and [K{(S)‐C₅H₄CH(Ph)CH₂NMe₂}] with the cyclooctatetraenyl lanthanide chlorides [(η⁸‐C₈H₈)Ln(μ‐Cl)(THF)]₂ (Ln = Sm, Lu) yield the mixed cyclooctatetraenyl cyclopentadienyl lanthanide complexes [(η⁸‐C₈H₈)Sm{(S)‐η⁵ : η¹‐C₅H₄CH₂CH(Me)OMe}] ( 1 a ), [(η⁸‐C₈H₈)Ln{(S)‐η⁵ : η¹‐C₅H₄CH₂CH(Me)NMe₂}] (Ln = Sm ( 2 a ), Lu ( 2 b )) and [(η⁸‐C₈H₈)Ln{(S)‐η⁵ : η¹‐C₅H₄CH(Ph)CH₂NMe₂}] (Ln = Sm ( 3 a ), Lu ( 3 b )). For comparison, the achiral compounds [(η⁸‐C₈H₈)Ln{η⁵ : η¹‐C₅H₄CH₂CH₂NMe₂}] (Ln = Sm ( 4 a ), Lu ( 4 b )) are synthesized in an analogous manner. ¹H‐, ¹³C‐NMR‐, and mass spectra of all new compounds as well as the X‐ray crystal structures of 3 b and 4 b are discussed.     

Kristallstrukturen,spektroskopische Charakterisierung und Normalkoordinatenanalyse von (n‐Bu4N)2[M(ECN)4] (M = Pd,Pt; E = S,Se)

Crystal Structures, Spectroscopic Analysis, and Normal Coordinate Analysis of ( n ‐Bu₄N)₂[M(ECN)₄] (M = Pd, Pt; E = S, Se) The reaction of (NH₄)₂[PdCl₄] or K₂[PtCl₄] with KSCN or KSeCN in aqueous solutions yields the complex anions [Pd(SCN)₄]^2–, [Pt(SCN)₄]^2– and [Pt(SeCN)₄]^2–, which are converted into (n‐Bu₄N) salts with (n‐Bu₄N)HSO₄. (n‐Bu₄N)₂[Pd(SeCN)₄] is formed by treatment of (n‐Bu₄N)₂[PdCl₄] with (n‐Bu₄N)SeCN in acetone. X‐ray structure determinations on single crystals of (n‐Bu₄N)₂[Pd(SCN)₄] (monoclinic, space group P2₁/n, a = 13.088(3), b = 12.481(2), c = 13.574(3) Å, β = 91.494(15)°, Z = 2), (n‐Bu₄N)₂[Pd(SeCN)₄] (monoclinic, space group P2₁/n, a = 13.171(2), b = 12.644(2), c = 13.560(2) Å, β = 91.430(11)°, Z = 2) and (n‐Bu₄N)₂[Pt(SeCN)₄] (monoclinic, space group P2₁/n, a = 13.167(2), b = 12.641(1), c = 13.563(2) Å, β = 91.516(18)°, Z = 2) reveal, that the compounds crystallize isotypically and the complex anions are centrosymmetric and approximate planar. In the Raman spectra the metal ligand stretching modes of (n‐Bu₄N)₂[Pd(SCN)₄] ( 1 ) and (n‐Bu₄N)₂[Pt(SCN)₄] ( 3 ) are observed in the range of 260–303 cm^–1 and of (n‐Bu₄N)₂[Pd(SeCN)₄] ( 2 ) and (n‐Bu₄N)₂[Pt(SeCN)₄] ( 4 ) in the range of 171–195 cm^–1. The IR and Raman spectra are assigned by normal coordinate analysis using the molecular parameters of the X‐ray determination. The valence force constants are f_d(PdS) = 1.17, f_d(PdSe) = 1.17, f_d(PtS) = 1.44 and f_d(PtSe) = 1.42 mdyn/Å. The ⁷⁷Se NMR resonances are 23 for 2 , –3 for 4 and the ¹⁹⁵Pt NMR resonances 549 for 3 and 130 ppm for 4 .