Bi9Rh2Br3, Bi9Rh2I3 und Bi9Ir2I3 – Eine neue Strukturfamilie quasi‐eindimensionaler Metalle

Bi₉Rh₂Br₃, Bi₉Rh₂I₃, and Bi₉Ir₂I₃ – A New Structure Family of Quasi One‐dimensional Metals Bi₉Rh₂Br₃, Bi₉Rh₂I₃, and Bi₉Ir₂I₃ were synthesized from the elements using niobium bromides or iodides as auxiliaries to modify the partial pressures in the course of the reaction. X‐ray diffraction on single crystals showed that the compounds are not isomorphous. However they have a common structural principle: strands of condensed [MBi₈] polyhedra, which are separated by halide anions. The spatial arrangement of the [MBi_1/1Bi_7/2] strands differs with the combination of elements: In Bi₉Rh₂I₃ (monoclinic, P2₁/m (no. 11), a = 775.6(1), b = 1374.9(2), c = 901.1(2) pm, β = 109.29(2)°) all strands are oriented parallel to each other. Bi₉Rh₂Br₃ (monoclinic, P2₁/m (no. 11), a = 927.98(8), b = 1372.1(1), c = 1992.7(2) pm, β = 100.77(1)°) and Bi₉Ir₂I₃ (orthorhombic, Pnma (no. 62), a = 2677.5(5), b = 1394.2(2), c = 967.6(1) pm) are ordered polytypes with two orientations changing in alternating layers of characteristic widths. The experimental proof of metallic conductivity in Bi₉Ir₂I₃ supports the assumption of delocalised electrons inside the  [MBi_1/1Bi_7/2] strands. The magnetic susceptibility of Bi₉Rh₂Br₃ increases slowly with decreasing temperature and shows a local maximum at about 14 K.     

Synthesen,Kristallstrukturen und Drillingsbildung der Cluster‐Trimere Bi2[PtBi6Br12]3 und Bi2[PtBi6I12]3

Syntheses, Crystal Structures, and Triple Twinning of the Cluster Trimers Bi₂[PtBi₆Br₁₂]₃ and Bi₂[PtBi₆I₁₂]₃ Melting reactions of Bi with Pt and BiX₃ (X = Br, I) yield shiny black, air insensitive crystals of the subhalides Bi₂[PtBi₆X₁₂]. Bi₂[PtBi₆Br₁₂]₃ crystallizes in the monoclinic space group C2/m with lattice parameters a = 1617.6(2) pm, b = 1488.5(1) pm, c = 1752.4(2) pm, and β = 110.85(4)°. Bi₂[PtBi₆I₁₂]₃ adopts the triclinic space group with pseudo‐monoclinic lattice parameters a = 1711.2(2) pm, b = 1585.1(1) pm, c = 1865.7(2) pm, and α = 90°, β = 111.15(4)°, γ = 90°. The two homoeotypic compounds consist of cuboctahedral [Pt^?IIBi^II₆X^?I₁₂]^2? clusters that are concatenated into linear trimers by Bi^III atoms. The ordered distribution of Bi^III atoms destroys the inherent threefold rotation axes in the packing of cluster anions. As a consequence of the pseudosymmetry the crystals are triple twinned along [201]. Due to different orientations of the cluster trimers there are two Bi^II···X inter‐cluster bridges per Bi^II atom in Bi₂[PtBi₆Br₁₂]₃ but only one bridge in Bi₂[PtBi₆I₁₂]₃. The structure of the iodine compound can be deduced from the NaCl structure type, leaving 37 of 96 atomic positions unoccupied. The arrangement of the cuboctahedral clusters follows the motif of a body‐centered cubic packing.     

Einkristalluntersuchungen an LiMF6 (M = Rh,Ir), Li2RhF6 und K2IrF6

Single Crystal Investigations on LiMF₆ (M = Rh, Ir), Li₂RhF₆, and K₂IrF₆ LiRhF₆, LiIrF₆, Li₂RhF₆, and K₂IrF₆ were obtained again, but for the first time investigated by single crystal X‐ray methods. Rubyred LiRhF₆ and yellow LiIrF₆ crystallize isostructural in the trigonal space group R3 – C²_3i (Nr. 148) with the lattice parameters LiRhF₆: a = 502.018(7) pm, c = 1355.88(3) pm, Z = 3 and d(Rh–F) = 185.5(1) pm; LiIrF₆: a = 506.148(4) pm, c = 1362.60(2) pm, Z = 3, d(Ir–F) = 187.5(3) pm (LiSbF₆‐Typ). Yellow Li₂RhF₆ crystallizes tetragonal in the space group P4₂/mnm – D¹⁴_4h (Nr. 136) with a = 463.880(8) pm, c = 905.57(2) pm, Z = 2 and d(Rh–F) = 190.3(4)–191.4(3) pm (Trirutil‐Typ). Yellow K₂IrF₆ crystallizes trigonal in the space group P3m1 – D³_3d (Nr. 164) with a = 578.88(7) pm, c = 465.06(5) pm, Z = 1 and d(Ir–F) = 194.0(6) pm, isotypic with K₂GeF₆.     

Synthesen,Eigenschaften und Kristallstrukturen der Cluster‐Salze Bi6[PtBi6Cl12] und Bi2/3[PtBi6Cl12]

Syntheses, Properties and Crystal Structures of the Cluster Salts Bi₆[PtBi₆Cl₁₂] and Bi_2/3[PtBi₆Cl₁₂] Melting reactions of Bi with Pt and BiCl₃ yield shiny black, air insensitive crystals of the subchlorides Bi₆[PtBi₆Cl₁₂] and Bi_2/3[PtBi₆Cl₁₂]. Despite the substantial difference in the bismuth content the two compounds have almost the same pseudo‐cubic unit cell and follow the structural principle of a CsCl type cluster salt. Bi₆[PtBi₆Cl₁₂] consists of cuboctahedral [PtBi₆Cl₁₂]^2? clusters and Bi₆²⁺ polycations (a = 9.052(2) Å, α = 89.88(2)°, space group P 1, multiple twins). In the electron precise cluster anion, the Pt atom (18 electron count) centers an octahedron of Bi atoms whose edges are bridged by chlorine atoms. The Bi₆²⁺ cation, a nido cluster with 16 skeletal electrons, has the shape of a distorted octahedron with an opened edge. In Bi_2/3[PtBi₆Cl₁₂] the anion charge is compensated by weakly coordinating Bi³⁺ cations which are distributed statistically over two crystallographic positions (a = 9.048(2) Å, α = 90.44(3)°, space group ). Bi₆[PtBi₆Cl₁₂] is a semiconductor with a band gap of about 0.1 eV. The compound is diamagnetic at room temperature though a small paramagnetic contribution appears towards lower temperature.     

Clusterkomplexe [M2Rh(μ‐PCy2)(μ‐CO)2(CO)8] mit triangularem Metallgerüst RhM2 (M = Mn,Re; M2 = MnRe): Synthese,Struktur, Ringöffnungen und Katalysatoreigenschaften für die Isomerisierung und Hydroformylierung von 1‐Hexen

Cluster Complexes [M₂Rh(μ‐PCy₂)(μ‐CO)₂(CO)₈] with Triangular Core of RhM₂ (M = Re, Mn; M₂ = MnRe): Synthesis, Structure, Ring Opening Reaction, and Properties as Catalysts for Hydroformylation and Isomerisation of 1‐Hexene The salts PPh₄[M₂(μ‐H)(μ‐PCy₂)(CO)₈] and Rh(COD)[ClO₄] were in equimolar amounts reacted at –40 to –15 °C in the presence of CO_(g) in CH₂Cl₂/methanol solution under release of PPh₄[ClO₄] to intermediates. Such species formed in a selective reaction the unifold unsaturated 46 valence electrons title compounds [M₂Rh(μ‐PCy₂)(μ‐CO)₂(CO)₈] (M = Re 1 , Mn 2 ; M₂ = MnRe 3 ) in yields of > 90%; analogeous the derivatives with the PPh₂ bridge could the obtained (M = Re 4 , Mn 5 ). From these clusters the molecular structure of 2 was determined by a single crystal X‐ray analysis. The exchange of the labil CO ligand attached at the rhodium ring atom in 1 – 3 against selected tertiary and secondary phosphanes in solution gave the substitution products [M₂RhL(μ‐PCy₂)(μ‐CO)₂(CO)₇] (M = Re: L = PMe₃ 6 , P(n‐Bu)₃ 7 , P(n‐C₆H₄SO₃Na)₃ 8 , HPCy₂ 9 , HPPh₂ 10 , HPMen₂ 11 , M₂ = MnRe: L = HPCy₂ 12 ) nearly quantitative. Such dimanganese rhodium intermediates ligated with secondary phosphanes were converted in a subsequent reaction to the ring‐opened complexes [MnRh(μ‐PCy₂)(μ‐H)(CO)₅Mn(μ‐PR₂)(CO)₄] (M = Mn: R = Cy 13 , Ph 14 , Mn 15 ). The molecular structure of 13 , which showed in the time scale of the ³¹P NMR method a fluxional behaviour, was determined by X‐ray structure analysis. All products obtained were always characterized by means of υ(CO)Ir, ¹H and ³¹P NMR measurements. From the reactants of hydroformylation process, CO_(g) 1 – 2 in different solvents afforded at 20 °C under a reversible ring opening reaction the valence‐saturated complexes [MRh(μ‐PCy₂)(CO)₇M(CO)₅] (M = Re 16 , Mn 17 ), whereas the reaction of CO_(g) and the ring‐opened 13 to [MnRh(μ‐PCy₂)(μ‐H)(CO)₆Mn(μ‐PCy₂)(CO)₄] ( 18 ) was as well reversible. The molecular structures of 17 and 18 were determined by X‐ray analysis. The υ(CO)IR, ¹H and ³¹P NMR measurements in pressure‐resistant reaction vessels at 20 °C ascertained the heterolytic splitting of hydrogen in the reaction of 1 – 2 dissolved in CDCl₃ or THF‐d₈ under formation of product monoanions [M₂Rh(μ‐CO)(μ‐H)(μ‐PCy₂)(CO)₉]^– (M = Re, Mn), which also were formed by the reaction of NaBH₄ and 1 – 2 . Finally, the substrate 1‐hexene and 1 and 3 gave under the release of the labil CO ligand an η²‐coordination pattern of hexene, which was weekened going from the Re to the Mn neighbor atoms. After the results of the catalytic experiments with 1 and 2 as catalysts, such change in the bonding property revealed an advantageous formation of hydroformylation products for the dirhenium rhodium catalyst 1 and that of isomerisation products of hexene for the dimanganese rhodium catalyst 2 . Par example, 1 generated n‐heptanal/2‐methylhexanal in TOF values of 246 [h^–1] (n/iso = 3.4) and the c,t‐hexenes in that of 241 [h^–1]. Opposotite to this, 2 achieved such values of 55 [h^–1] (n/iso = 3.6) and 473 [h^–1]. A triphenylphosphane substitution product of 1 increased the activity of the hydroformylation reaction about 20%, accompanied by an only gradually improved selectivity. The hydrogenation products like alcohols and saturated hydrocarbons known from industrial hydroformylation processes were not observed. The metals manganese and rhenium bound at the rhodium reaction center showed a cooperative effect.     

Regioselektive Ringöffnungen von einfach ungesättigten triangularen Clusterkomplexen [M2Rh(μ‐PR2)(μ‐CO)2(CO)8] (M2 = Re2, Mn2; R = Cy,Ph; M2 = MnRe,R = Ph) mit Diphosphanen

Regioselective Ring Opening Reactions of Unifold Unsaturated Triangular Cluster Complexes [M₂Rh(μ‐PR₂)(μ‐CO)₂(CO)₈] (M₂ = Re₂, Mn₂; R = Cy, Ph; M₂ = MnRe, R = Ph) with Diphosphanes Equimolar amounts of the triangular title compounds and chelates of the type (Ph₂P)₂Z (Z = CH₂, DPPM ; C=CH₂, EPP ) react in thf solution at –40 to –20 °C under release of the labile terminal carbonyl ligand attached to the rhodium atom in good yields (70–90%) to ring‐opened unifold unsaturated complexes [MRh(μ‐PR₂)(CO)₄M(DPPM bzw. EPP)(μ‐CO)₂(CO)₃] (DPPM: M₂ = Re₂, R = Cy 1 , Ph 2 ; Mn₂, Cy 5 , Ph 6 ; MnRe, Cy 7 . EPP: M₂ = Re₂, R = Cy 8 ; Mn₂, Cy 10 ). Complexes 1 , 2 and 8 react subsequently under minor uptake of carbon monoxide and formation of the valence saturated complexes [ReRh(μ‐PR₂)(CO)₄M(DPPM bzw. EPP) (CO)₆] (DPPM: R = Cy 3 , Ph 4 . EPP: R = Cy 9 ). Separate experiments ascertained that the regioselective ring opening at the M–M‐edge of the title compounds is limited to reactions with diphosphanes chelates with only one chain member and that the preparation of the unsaturated complexes demands relatively good donor ability of both P atoms. As examples for both types of compounds the molecular structures of 8 and 3 have been determined from single crystal X‐ray structure analysis. Additionally all new compounds are identified by means of ν(CO)IR, ¹H‐ and ³¹P‐NMR data. This includes complexes with a modified chain member in 1 and 5 which, after deprotonation reaction to carbanionic intermediates, could be trapped with [PPh₃Au]⁺ cations as rac‐[MRh(μ‐PR₂)(CO)₄M((Ph₂P)₂CHAuPPh₃)(μ‐CO)₂(CO)₃] (M₂ = Re 17 , Mn 18 ) and products rac‐[MRh(μ‐PR₂)(CO)₄M((Ph₂P)₂CHCH₂R)(μ‐CO)₂(CO)₃] (M₂ = Re, R = Ph 19 , n‐Bu 21 , Me 23 ; Mn, Ph 20 , n‐Bu 22 , Me 24 ) which result from Michael‐type addition reactions of 8 or 10 with strong nucleophiles LiR.     

The Intermetalloid Clusters [Ni2Bi12]4+ and [Rh2Bi12]4+ – Ionothermal Synthesis,Crystal Structures,and Chemical Bonding

The intermetalloid clusters [M₂Bi₁₂]⁴⁺ (M = Ni, Rh) were synthesized as halogenido‐aluminates in Lewis‐acidic ionic liquids. The reaction of bismuth and NiCl₂ in [BMIm]Cl · 5AlCl₃ (BMIm = 1‐butyl‐3‐methylimidazolium) at 180 °C yielded black, triclinic (P1 ) crystals of [Ni₂Bi₁₂][AlCl₄]₃[Al₂Cl₇]. Black, monoclinic (P2₁/m) crystals of [Rh₂Bi₁₂][AlBr₄]₄ precipitated after dissolving the cluster salt Bi_12–xRhX_13–x (X = Cl, Br; 0 < x < 1) in [BMIm]Br·4.1AlBr₃ at 140 °C. In the cationic cluster [Ni₂Bi₁₂]⁴⁺, the nickel atoms center two base‐sharing square antiprisms of bismuth atoms (symmetry close to D_4h). The valence‐electron‐poorer rhodium‐containing cluster is a distorted variant of this motif: the terminating Bi₄ rings are folded to bicyclic “butterflies“ and the central square splits into two dumbbells (symmetry close to D_2h). DFT‐based calculations and real‐space bonding analyses place the intermetalloid units between a triple‐decker complex and a conjoined Wade‐Mingos cluster.     

X‐Ray Photoemission Studies of the Ternary Intermetallic Compounds Li2MGa and LiMGa2 (M = Rh,Pd, Ir,Pt)

X‐ray photoelectron and x‐ray excited Auger spectra were measured for the intermetallic compounds LiMGa₂ and Li₂MGa (M = Rh, Pd, Ir, Pt). The valence band spectra exhibit characteristic differences in the location of the M d‐band between group 9 elements (Rh, Ir) and group 10 elements (Pd, Pt) on one side and between LiMGa₂ and Li₂MGa on the other. The experimentally observed differences are in excellent agreement with results from band structure calculations. The combination of binding energy shifts with Auger kinetic energy shifts allowed a separation of initial and final state contributions. Core hole screening is very efficient in accordance with the metallic character of the investigated phases. The magnitude of the screening correlates with the theoretically predicted composition of the density of states at the Fermi level. Application of Wertheim's electrostatic model allowed to estimate the charge distribution for LiRhGa₂ and Li₂RhGa. The sign of the charges agrees with expectations that result from the Extended Zintl Concept. The results show, how dangerous it is to draw conclusions on the chemistry of such systems from photoemission data alone.     

Heterokuban‐Cluster‐Verbindungen (NEt4){Y=M[(μ3‐S)Re(CO)3]3(μ3‐E)} (M = W oder Mo,Y = O oder S,E = S oder Se): Strukturen,Spektroskopie und Elektrochemie

Heterocubane Cluster Compounds (NEt₄){Y=M[(μ₃‐S)Re(CO)₃]₃(μ₃‐E)} (M = W or Mo, Y = O or S, E = S or Se): Structures, Spectroscopy, and Electrochemistry Thiometallates [MS₄]^2– (M = Mo, W) or [WOS₃]^2– react with Re(CO)₅(O₃SCF₃) and Li₂E (E = S or Se) to yield the following compounds which were structurally characterized: (NEt₄){S=W[(μ₃‐S)Re(CO)₃]₃(μ₃‐S)}(NEt₄) ( 1 ), (NEt₄){O/S=W[(μ₃‐S)Re(CO)₃](μ₃‐S)}(NEt₄) ( 1 / 2 ), (mixed crystals), (NEt₄){S=W[(μ₃‐S)Re(CO)₃]₃(μ₃‐Se)}(NEt₄) ( 3 ) and (NEt₄){S=Mo[(μ₃‐S)Re(CO)₃]₃(μ₃‐S)}(NEt₄) ( 4 ). The heterocubane anions 1 – 4 contain electron‐rich centers such as rhenium(I) or sulfide whereas molybdenum(VI) or tungsten(VI) act as acceptor sites. Accordingly, the absorption spectra show long‐wavelength metal‐to‐ligand charge transfer transitions, and cyclic voltammetry reveals a quasi‐reversible reduction of the clusters. Although both six‐coordinate rhenium(I) and four‐coordinate metal(VI) centers are present in the clusters there is no evidence for significant metal‐to‐metal charge transfer interaction.     

Mg15Ir5Si2, ein Magnesium‐Iridiumsilicid mit isolierten Ir5Si2‐Baugruppen

Mg₁₅Ir₅Si₂ a Magnesium Iridium Silicide with Isolated Ir₅Si₂ Building Groups Mg₁₅Ir₅Si₂ (tetragonal, P4₂/n, a = 1371.7(1) pm, c = 873.0(2) pm, Z=4, 1497 reflections, 103 parameters, R1 = 0.048) was prepared by reaction of the elements at 900 °C in sealed tantalum ampoules. The compound is the silicide with the highest alkaline earth metal content known so far. It is the first example of a silicide with an isolated transition metal silicon building group embedded in a matrix of non‐transition metal atoms. The structure contains planar Ir₂SiIrSiIr₂ groups with silicon atoms in nearly trigonal planar coordination of three iridium atoms (d_Ir‐Si = 235 and 236 pm).     

Synthese und Struktur gemischt‐substituierter Dialane Al2X2{Si(SiMe3)3}2 · 2 THF (X = Cl,Br)

Synthesis and Structure of two Mixed Substituted Dialanes Al₂X₂{Si(SiMe₃)₃}₂ · 2 THF (X = Cl, Br) The syntheses of tris(trimethylsilyl)silyl (hypersilyl) and halide substituted dialanes Al₂X₂{Si(SiMe₃)₃}₂ · 2 THF (X = Cl, Br) are presented. The results of the X‐ray diffraction experiments are presented and discussed in comparison to the Al^III compounds AlBr₂Si(SiMe₃)₃ · THF and AlBr₃ · OPh₂.     

Ag3Bi14Br21: ein Subbromid mit Bi24+‐Hanteln und Bi95+‐Polyedern – Synthese,Kristallstruktur und Chemische Bindung

Ag₃Bi₁₄Br₂₁: a Subbromide with Bi₂⁴⁺ Dumbbells and Bi₉⁵⁺ Polyhedra – Synthesis, Crystal Structure and Chemical Bonding Black crystals of Ag₃Bi₁₄Br₂₁ = (Bi₉⁵⁺)[Ag₃Bi₃Br₁₅^3?](Bi₂Br₆^2?), the first argentiferous bismuth subhalide, were obtained from a stoichiometric melt of Ag, Bi, and BiBr₃. The compound crystallizes in the monoclinic space group P2₁/m with lattice parameters a = 1277.78(5) pm, b = 1466.87(6) pm, c = 1342.62(5) pm, and β = 108.47(1)° at 110(5) K. In contrast to all other bismuth subhalides that contain an electron‐rich transition metal, the silver atoms are not bonded to bismuth atoms. Instead they are integrated into the anionic bromometallate network, which consists of [MBr₆]‐octahedra (M = Ag, Bi) that share edges and vertices. These corrugated sheets alternate with tessellated layers formed by Bi₉⁵⁺ polycations and hitherto unknown (Bi^II₂Br₆)^2? groups. The latter anions contain Bi₂⁴⁺ dumbbells (299 pm) and can be represented by the structured formula [Br₂Bi^II(μ–Br)₂Bi^IIBr₂]^2?. The multi‐center bonding within the Bi₉⁵⁺ cluster and the bent single‐bond in the Bi₂ dumbbell can be visualized using the electron localization indicator (ELI‐D).     

[Ga6R8]2– (R = SiPh2Me): Eine metalloide Clusterverbindung mit einem unerwarteten Ga6‐Gerüst

[Ga₆R₈]^2– (R = SiPh₂Me): A Metalloid Cluster Compound with an Unexpected Ga₆‐Frame The reaction of a metastable solution of GaBr with a solution of LiSiPh₂Me in a toluene/THF mixture results in orange coloured crystals of [Ga₆(SiPh₂Me)₈]^2– · 2 [Li(THF)₄]⁺ ( 1 ). The unexpected structure of the planar Ga₆ frame (C_2h) could also be realized with the help of DFT calculation. DFT calculations furthermore show that 1 is energetically favoured against an octahedral Ga₆R₆^2– species and R₂. In contrast calculations for the similar Al and B species show that in these cases the octahedral entities are favoured. These results demonstrate that even for similar compounds of B, Al, and Ga Wade rules are too general and that they cannot predict the correct structure. Moreover the atomic arrangement within 1 shows that a structure is preferred which is also present in allotropic β‐Ga and that therefore clusters of this type should be called metalloid or more general elementoid.     

Ternary Rhodium Borides A3Rh5B2 (A = Mg,Sc) and Quaternary Derivatives A2MRh5B2. Preparation,Crystal Structure (M = Main Group and 3 d Elements), and Magnetism (M = Mn,Fe)

The new ternary rhodium borides Mg₃Rh₅B₂ and Sc₃Rh₅B₂ (P4/mbm, Z = 2; a = 943.4(1) pm, c = 292.2(1) pm and a = 943.2(1) pm, c = 308.7(1) pm, respectively) crystallize with the Ti₃Co₅B₂ type structure. Mg and Sc may in part be substituted by a variety of elements M. For M = Si and Fe, homogeneity ranges were found according to A_3–xM_xRh₅B₂ with 0 ≤ x ≤ 1.0 for A = Sc and with x up to 1.5 for A = Mg. Quaternary compounds with x = 1 (A₂MRh₅B₂: A/M in short) were prepared with M = Be, Al, Si, P, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Sn (Co, Ni only with A = Mg; Sn only with A = Sc; P, As with deficiencies). Single crystal X‐ray investigations show an ordered substitutional variant of the Ti₃Co₅B₂ type in which the M atoms are arranged in chains along [001] with intrachain and interchain M–M distances of about 300 pm and 660 pm, respectively. Measuring the magnetisation (1.7 K–800 K) of the phases Mg/Mn, Sc/Mn, Mg/Fe, and Sc/Fe reveals antiferromagnetic interactions in the first and dominating ferromagnetic intrachain interactions in the remaining ones. Interchain interactions of antiferromagnetic nature are evident in Sc/Mn and Mg/Fe leading to metamagnetism below T_N = 130 K, while Sc/Fe behaves ferromagnetically below T_C = 450 K. The overall trend towards stronger ferromagnetic interactions with increasing valence electron concentration is obvious.     

Synthese,Kristallstruktur und Eigenschaften der käfigartigen,sechsbasigen Säure P12S12N8(NH)6 · 14 H2O sowie ihrer Salze Li6[P12S12N14] · 26 H2O, (NH4)6[P12S12N14] · 10 H2O und K6[P12S12N14] · 8 H2O

Syntheses, Crystal Structure, and Properties of the Cage‐like, Hexaacidic P₁₂S₁₂N₈(NH)₆ · 14 H₂O and its Salts Li₆[P₁₂S₁₂N₁₄] · 26 H₂O, (NH₄)₆[P₁₂S₁₂N₁₄] · 10 H₂O, and K₆[P₁₂S₁₂N₁₄] · 8 H₂O The cage‐like acid P₁₂S₁₂N₈(NH)₆ · 14 H₂O was obtained by the reaction of KSCN with P₄S₁₀ via the formation of K₆[P₁₂S₁₂N₁₄] · 8 H₂O and subsequent ion exchange reactions in aqueous solution. Starting from the acid the salts Li₆[P₁₂S₁₂N₁₄] · 26 H₂O and (NH₄)₆[P₁₂S₁₂N₁₄] · 10 H₂O were synthesized. According to X‐ray single‐crystal structure analyses the compounds are built up by isosteric P–N cages [P₁₂S₁₂N^[3]₈N^[2]₆]^6–. Each of them is made up of twelve P₃N₃ rings, which exclusively exhibit the boat conformation. The cages have the idealized symmetry 2/m3; P₁₂S₁₂N₈(NH)₆ · 14 H₂O: P1, a = 1119.11(7), b = 1123.61(7), c = 1125.80(6) pm, α = 80.186(4), β = 60.391(4), γ = 60.605(4)°, Z = 1; Li₆[P₁₂S₁₂N₁₄] · 26 H₂O: Fm3, a = 1797.4(1) pm, Z = 4; (NH₄)₆[P₁₂S₁₂N₁₄] · 10 H₂O: P6₃, a = 1153.2(1), c = 2035.6(2) pm, Z = 2; K₆[P₁₂S₁₂N₁₄] · 8 H₂O: R3c, a = 1142.37(5), c = 6009.6(3) pm, Z = 6. In the crystal the cages of the acid are crosslinked via hydrate molecules by hydrogen bonds. The cations in the salts show a high‐mobility and are located between the cages.     

Synthese,Struktur und Eigenschaften von [nacnac]MX3‐Verbindungen (M = Ge,Sn; X = Cl,Br, I)

Synthesis, Structure, and Properties of [nacnac]MX₃ Compounds (M = Ge, Sn; X = Cl, Br, I) Reactions of [nacnac]Li [(2,6‐ⁱPr₂C₆H₃)NC(Me)C(H)C(Me)N(2,6‐ⁱPr₂C₆H₃)]Li ( 1 ) with SnX₄ (X = Cl, Br, I) and GeCl₄ in Et₂O resulted in metallacyclic compounds with different structural moieties. In the [nacnac]SnX₃ compounds (X = Cl 2 , Br 3 , I 4 ) the tin atom is five coordinated and part of a six‐membered ring. The Sn–N‐bond length of 3 is 2.163(4) Å and 2.176(5) Å of 4 . The five coordinated germanium of the [nacnac]GeCl₃ compound 5 shows in addition to the three chlorine atoms further bonds to a carbon and to a nitrogen atom. In contrast to the known compounds with the [nacnac] ligand the afore mentioned reaction creates a carbon–metal‐bond (1.971(3) Å) forming a four‐membered ring. The Ge–N bond length (2.419(2) Å) indicates the formation of a weakly coordinating bond.     

MAl2Ta35O70 (M = Na,K, Rb), niedervalente Oxotantalate mit isolierten kuboktaedrischen Ta6O12-Clustern

MAl₂Ta₃₅O₇₀ (M = Na, K, Rb), Low-Valent Oxotantalates with Discrete Cuboctahedral Ta₆O₁₂ Clusters The title compounds were prepared by reducing Ta₂O₅ with tantalum and aluminium in the presence of alkali metal carbonates at 1650 K. NaAl₂Ta₃₅O₇₀ was characterized by means of a single crystal X-ray structure determination: space group P 3, lattice parameters a = 780.15(7) pm, c = 2621.7(8) pm, Z = 1, 167 variables, R_F = 0.048. The structure can be described in terms of a close packing of oxide ions with specific defects. The sequence of the layers is hhcchchcchh. The characteristic structural units are Ta₆O₁₂ clusters being substantially stabilized by Ta–Ta bonding (d_Ta–Ta = 279.3–283.3 pm, 14 electrons per cluster). The sodium cations occupy acentrically and statistically half of the anti-cuboctahedral sites. The compounds are semiconductors with band gaps E_a of 0.2 to 0.3 eV.     

Selektive Darstellung zweifach diorganophosphido-verbrückter Metallatetrahedrane [Re2(MPR3)2(μ-PR2)2(CO)6] mit Re2M2-Metallgerüst (M = Au,Ag)

Selective Preparation of Twofold Diorganophosphido-bridged Metallatetrahedranes [Re₂(MPR₃)₂(μ-PR₂)₂(CO)₆] with Re₂M₂ Metal Core (M = Au, Ag) The reaction of the in situ prepared salt Li[Re₂(AuPR)(μ-PR₂)(CO)₇Cl] (R = R′ = Cy ( 1 a ), R = Cy, R′ = Ph ( 1 b ), R = Ph, R′ = Cy ( 1 c ), R = Ph, R′ = Et ( 1 d ), R = Ph, R′ = Ph ( 1 e )) with one equivalent HPR in methanolic solution at room temperature yields the neutral cluster complexes [Re₂(AuPR)(μ-PR₂)(CO)₇(ax-HPR) (R = R′ = R″ = Cy ( 2 a ), Ph ( 2 b ), R = R′ = Cy, R″ = Et ( 2 c ), R = Cy, R′ = R″ = Ph ( 2 d ), R = Cy, R′ = Ph, R″ = Et ( 2 e ), R = R″ = Ph, R′ = Et ( 2 f ), R = Ph, R′ = Cy, R″ = Et (2 g)). Photochemically induced these complexes react in the presence of the organic base DBU in THF solution to give the doubly phosphido bridged anions Li[Re₂(AuPR)(μ-PR₂)(μ-PR)(CO)₆], which were characterized as salts PPh₄[Re₂(AuPR)(μ-PR₂)(μ-PR)(CO)₆] (R = R′ = R″ = Ph ( 3 a ), R = R′ = Ph, R″ = Cy ( 3 b ), R = Ph, R′ = Cy, R″ = Et ( 3 c ), R = R″ = Ph, R′ = Et ( 3 d )). These precursor complexes 3 then react with one equivalent of ClMPR (M = Au, Ag) to doubly phosphido bridged metallatetrahedranes [Re₂(MPR₃)₂(μ-PR₂)(μ-PR)(CO)₆] (M = Au, R = R′ = R″ = Ph ( 4 a ), M = Au, R′ = Et, R = R″ = Ph ( 4 b ), M = Au, R = R′ = Ph, R″ = Cy ( 4 c ), M = Au, R = Cy, R′ = Ph, R″ = Et ( 4 d ), M = Ag, R = R′ = R″ = Ph ( 4 e )). All isolated cluster complexes were characterized and identified by the following analytical methods: NMR- (¹H, ³¹P) and ν(CO) IR-spectroscopy and, additionally, complexes 2 b , 4 a and 4 e by X-ray structure analysis.     

Bismut(II)-chalkogenometallate(III) Bi2M4X8, Verbindungen mit Bi24+-Hanteln (M = Al,Ga; X = S,Se)

Bismuth(II) Chalcogenometallates(III) Bi₂M₄X₈, Compounds with Bi₂⁴⁺ Dumbbells (M = Al, Ga and X = S, Se) The ternary bismuth(II) chalcogenometallates(III) Bi₂M₄X₈ (with M = Al, Ga and X = S, Se) were synthesized from the binary chalcogenides M₂X₃ and Bi₂X₃ and elementary bismuth. All compounds are diamagnetic semiconductors with E_g (opt.) = 1.8–2.7 eV. The phases (except Bi₂Al₄Se₈) are thermodynamically stable and decompose peritectically above 965–1020 K. Bi₂Al₄Se₈ is metastable below 825 K and is obtained only by rapid quenching from T > 825 K. The isotypic compounds crystallize in a new tetragonal tP28 structure type (P4/nnc). The characteristic unit is the hitherto unknown clustercation Bi₂⁴⁺, with the mean bond length d(Bi–Bi) = 314.2 pm, the Raman frequency 102 cm^–1 ≤ ν_s ≤ 108 cm^–1, and the mean force constant of f = 0.68 N · cm^–1. The Electron Localization Function, ELF, shows the covalent Bi–Bi bond, the lone electron pairs of the ψ-octahedrally coordinated Bi(II) cations, and the polar character of the Bi–X bonds.     

[PtIn6][GaO4]2 – das erste Oxid mit [PtIn6]‐Oktaedern. Darstellung,Charakterisierung und Rietveldverfeinerung – mit einer Bemerkung zur Mischkristallreihe [PtIn6][GaO4]2–x[InO4]x (0 < x ≤ 1)

[PtIn₆][GaO₄]₂ – The First Oxide Containing [PtIn₆] Octahedra. Preparation, Characterisation, and Rietveld Refinement – With a Remark to the Solid Solution Series [PtIn₆][GaO₄]_2‐x[InO₄]_x (0 < x ≤ 1) The novel oxides [PtIn₆][GaO₄]_2–x[InO₄]_x (0 < x ≤ 1) are formed by heating intimate mixtures of Pt, In, In₂O₃, and Ga₂O₃ in the corresponding stoichiometric ratio in corundum crucibles under an atmosphere of argon (1220 K, 70 h). The compounds are black, stable in air at room temperature, reveal a semiconducting behaviour, and decompose only in oxidizing acids. X‐ray powder diffraction patterns can be indexed by assuming a face centered cubic unit cell with lattice parameters ranging from a = 1001.3(1) pm (x = 0) to a = 1009.3(1) pm (x = 1). According to a Rietveld refinement [PtIn₆][GaO₄]₂ crystallizes isotypic to the mineral Pentlandite (Fm3m, Z = 4, R(profile) = 6.11%, R(intensity) = 3.95%). The characteristic building units are isolated [PtIn₆]¹⁰⁺ octahedra which are linked via [GaO₄]^5– tetrahedra to a three dimensional framework. Starting from [PtIn₆][GaO₄]₂ the substitution of Ga³⁺ ions by larger In³⁺ ions leads to the formation of a solid solution series according to the general formula [PtIn₆][GaO₄]_2–x[InO₄]_x and becomes apparent in an increase of the lattice parameter.