Reactions of metallocenes during intercalation into the layered TiSe2 lattice

The intercalation of metallocenes (Cp₂Co, Cp₂Fe, and Cp₂Ni, where Cp is η⁵-C₅H₅) from the gas phase into the TiSe₂ lattice and of cobaltocene from solutions in acetonitrile, carbon tetrachloride, and chloroform into TiSe₂ was studied. The insertion of metallocenes from the gas phase into the TiSe₂ lattice gives rise to the TiSe₂(Cp₂M)_0.3 compounds (M = Co or Fe) having the same stoichiometry. The reactions with the use of acetonitrile as the solvent for metallocenes, which facilitates the insertion, afford not only the intercalation complex but also the reaction product of metallocene and acetonitrile, viz., (η ⁵-C₅H₅)Co(η⁴-C₅H₅CH₂CN) (1). In the reactions of cobaltocene with chloroform or carbon tetrachloride in the presence of titanium diselenide, only the addition product, viz., (η ⁵-C₅H₅)Co(η₄-C₅H₅CCl₃) (2), was isolated. The structures of complexes 1 and 2 were studied by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 876–880, May, 2007.     

Suppression of the Charge Density Wave State in Two‐Dimensional 1T‐TiSe2 by Atmospheric Oxidation

Two‐dimensional (2D) metallic transition‐metal dichalcogenides (TMDCs), such as 1T ‐TiSe₂, have recently emerged as unique platforms for exploring their exciting properties of superconductivity and the charge density wave (CDW). 2D 1T ‐TiSe₂ undergoes rapid oxidation under ambient conditions, significantly affecting its CDW phase‐transition behavior. We comprehensively investigate the oxidation process of 2D TiSe₂ by tracking the evolution of the chemical composition and atomic structure with various microscopic and spectroscopic techniques and reveal its unique selenium‐assisting oxidation mechanism. Our findings facilitate a better understanding of the chemistry of ultrathin TMDCs crystals, introduce an effective method to passivate their surfaces with capping layers, and thus open a way to further explore the functionality of these materials toward devices.     

Thermodynamic properties of titanium selenides with variable composition TiSe2-TiSe1.80

The thermodynamic investigation of the system TiSe₂-TiSe_1.80 was carried out by the static method of vapor pressure measurements using the quartz membrane-zero manometers in the temperature range from 713 to 1395 K. The analysis of the p _Se-T-x dependences obtained showed that titanium diselenide formed a continuous solid solution. The enthalpies and entropies of dissociation processes of TiSe _x were derived from the experimental data. The standard enthalpies of formation, the absolute entropies, and the free Gibbs energies of formation of selenides belonging to the homogeneity region of TiSe₂ were estimated using literature data. The obtained set of thermodynamic characteristics may be used for the calculation of phase equilibria and for thermodynamic modeling in the system Ti-Se.     

Neue Phosphor-verbrückte Übergangsmetall-Komplexe Die Kristallstrukturen von [Co4(CO)10(PiPr)2], [Fe3(CO)9(PtBu)(PPh)], [Cp3Fe3(CO)2(PPtBu)(PtBu)], [(NiPPh3)2(PiPr)6], [(NiPPh3)Ni{(PtBu)3}2] und [Ni8(PtBu)6(PPh3)2]

New Phosphorus-bridged Transition Metal Complexes The Crystal Structures of [Co₄(CO)₁₀(PⁱPr)₂], [Fe₃(CO)₉(P^tBu)(PPh)], [Cp₃Fe₃(CO)₂(PP^tBu)· (P^tBu)], [(NiPPh₃)₂(PⁱPr)₆], [(NiPPh₃)Ni{(P^tBu)₃}₂], and [Ni₈(P^tBu)₆(PPh₃)₂] By the reaction of cyclophosphines with transition metal carbonyl-derivatives polynuclear complexes are built, in which the PR-ligands (R = organic group) are bonded in different ways to the metal. Depending on the reaction conditions the following compounds can be characterized: [Co₄(CO)₁₀ · (PⁱPr)₂] ( 2 ), [Fe₃(CO)₉(P^tBu)(PPh)] ( 3 ), [Cp₃Fe₃(CO)₂(PP^tBu) · (P^tBu)] ( 4 ), [(NiPPh₃)₂(PⁱPr)₆] ( 5 ), [(NiPPh₃)Ni{(P^tBu)₃}₂] ( 6 ) and [Ni₈(P^tBu)₆(PPh₃)₂] ( 7 ). The structures of 2–7 were obtained by X-ray single crystal structure analysis ( 2 : space group Pccn (No. 56), Z = 4, a = 1001,4(2) pm, b = 1375,1(3) pm, c = 1675,5(3) pm; 3 : space group P2₁ (No. 4), Z = 2, a = 914,3(4) pm, b = 1268,7(4) pm, c = 1028,2(5) pm, β = 101,73(2)°; 4 : space group P1 (No. 2), Z = 2, a = 946,0(5) pm, b = 1074,4(8) pm, c = 1477,7(1,0) pm, α = 107,63(5)°, β = 94,66(5)°, γ = 111,04(5)°; 5 : space group P1 (No. 2), Z = 2, a = 1213,6(2) pm, b = 1275,0(2) pm, c = 2038,8(4) pm, α = 92,810(10)°, β = 102,75(2)°, γ = 93,380(10)°; 6 : space group P1 (No. 2), Z = 2, a = 1157,5(5) pm, b = 1371,9(6) pm, c = 1827,6(10) pm; α = 69,68(3)°, β = 80,79(3)°, γ = 69,36(3)°; 7 : space group P3 (No. 147), Z = 1, a = 1114,1(2) pm, b = 1114,1(2) pm, c = 1709,4(3) pm).     

Neue Phosphido-verbrückte Mehrkernkomplexe des Ag,Cd und Zn Die Kristallstrukturen von [Ag4(PPh2)4(PMe3)4], [Ag6(PPh2)6(PtBu3)2] und [M4Cl4(PPh2)4(PnPr3)2] (M = Zn,Cd)

New Phosphido-bridged Multinuclear Complexes of Ag, Cd and Zn. The Crystal Structures of [Ag₄(PPh₂)₄(PMe₃)₄], [Ag₆(PPh₂)₆(P^tBu₃)₂] and [M₄Cl₄(PPh₂)₄(PⁿPr₃)₂] (M = Zn, Cd) AgCl reacts with Ph₂PSiMe₃ in the presence of a tertiary Phosphine PMe₃ or P^tBu₃ to form the multinuclear complexes [Ag₄(PPh₂)₄(PMe₃)₄] ( 1 ) and [Ag₆(PPh₂)₆(P^tBu₃)₂] ( 2 ). In analogy to that MCl₂ reacts with Ph₂PSiMe₃ in the presence of PⁿPr₃ to form the two multinuclear complexes [M₄Cl₄(PPh₂)₄(PⁿPr₃)₂] (M = Zn ( 3 ), Cd ( 4 )). The structures were characterized by X-ray single crystal structure analysis ( 1 : space group Pna2₁ (Nr. 33), Z = 4, a = 1 313.8(11) pm, b = 1 511.1(6) pm, c = 4 126.0(18) pm, 2 : space group P–1 (Nr. 2), Z = 2, a = 1 559.0(4) pm, b = 1 885.9(7) pm, c = 2 112.4(8) pm, α = 104.93(3)°, β = 94.48(3)°, γ = 104.41(3)°; 3 : space group C2/c (Nr. 15), Z = 4, a = 2 228.6(6) pm, b = 1 847.6(6) pm, c = 1 827.3(6) pm, β = 110.86(2); 4 : space group C2/c (Nr. 15), Z = 4, a = 1 894.2(9) pm, b = 1 867.9(7) pm, c = 2 264.8(6) pm, β = 111.77(3)°). 3 and 4 may be considered as intermediates on the route towards polymeric [M(PPh₂)₂]_n (M = Zn, Cd).     

LiLa2F3(SO4)2 und LiEr2F3(SO4)2: Fluoridsulfate der Selten‐Erd‐Elemente mit Lithium

LiLa₂F₃(SO₄)₂ and LiEr₂F₃(SO₄)₂: Fluoride‐Sulfates of the Rare‐Earth Elements with Lithium The reaction of LiF with the anhydrous sulfates M₂(SO₄)₃ (M = La, Er) in sealed gold ampoules yields single crystals of the pseudo quaternary compounds LiLa₂F₃(SO₄)₂ and LiEr₂F₃(SO₄)₂. According to X‐ray single crystal investigations, LiLa₂F₃(SO₄)₂ crystallizes with the monoclinic (I2/a, Z = 4, a = 828.3(2), b = 694.7(1), c = 1420.9(3) pm, β = 95.30(2)°, R_all = 0.0214) and LiEr₂F₃(SO₄)₂ with the orthorhombic crystal system (Pbcn, a = 1479.1(2), b = 633.6(1), c = 813.7(1) pm, R_all = 0.0229). A common feature of both structures is a dimeric unit of metal atoms connected via three fluoride ions. This leads to relatively short metal‐metal distances (La³⁺–La³⁺: 389 pm, Er³⁺–Er³⁺: 355 pm). In LiLa₂F₃(SO₄)₂, Li⁺ is surrounded by four oxygen atoms of four sulfate groups and one fluoride ion in form of a trigonal bipyramid, in LiEr₂F₃(SO₄)₂ two further fluoride ligands are attached.     

Synthese und Struktur der Phosphor-verbrückten Übergangsmetallkomplexe [Fe2(CO)6(PR)6] (R = tBu,iPr), [Fe2(CO)4(PiPr)6], [Fe2(CO)3Cl2(PtBu)5], [Co4(CO)10(PiPr)3], [Ni5(CO)10(PiPr)6] und [Ir4(C8H12)4Cl2(PPh)4]

Synthesis and Structure of the Phosphorus-bridged Transition Metal Complexes [Fe₂(CO)₆(PR)₆] (R = ^tBu, ⁱPr), [Fe₂(CO)₄(PⁱPr)₆], [Fe₂(CO)₃Cl₂(P^tBu)₅], [Co₄(CO)₁₀(PⁱPr)₃], [Ni₅(CO)₁₀(PⁱPr)₆], and [Ir₄(C₈H₁₂)₄Cl₂(PPh)₄] (P^tBu)₃ and (PⁱPr)₃ react with [Fe₂(CO)₉] to form the dinuclear complexes [Fe₂(CO)₆(PR)₆] (R = ^tBu: 1 ; ⁱPr: 2 ). 2 is also formed besides [Fe₂(CO)₄(PⁱPr)₆] ( 3 ) in the reaction of [Fe(CO)₅] with (PⁱPr)₃. When PⁱPr(P^tBu)₂ and PⁱPrCl₂ are allowed to react with [Fe₂(CO)₉] it is possible to isolate [Fe₂(CO)₃Cl₂(P^tBu)₅] ( 4 ). The reactions of (PⁱPr)₃ with [Co₂(CO)₈] and [Ni(CO)₄] lead to the tetra- and pentanuclear clusters [Co₄(CO)₁₀(PⁱPr)₃] ( 5 ), [Ni₄(CO)₁₀(PⁱPr)₆] [2] and [Ni₅(CO)₁₀(PⁱPr)₆] ( 6 ). Finally the reaction of [Ir(C₈H₁₂)Cl]₂ with K₂(PPh)₄ leads to the complex [Ir₄(C₈H₁₂)₄Cl₂(PPh)₄] ( 7 ). The structures of 1–7 were obtained by X-ray single crystal structure analysis (1: space group P2₁/c (Nr. 14), Z = 8, a = 1 758.8(16) pm, b = 3 625.6(18) pm, c = 1 202.7(7) pm, β = 90.07(3)°; 2 : space group P1 (Nr. 2), Z = 1, a = 880.0(2) pm, b = 932.3(3) pm, c = 1 073.7(2) pm, α = 79.07(2)°, β = 86.93(2)°, γ = 72.23(2)°; 3 : space group Pbca (Nr. 61), Z = 8, a = 952.6(8) pm, b = 1 787.6(12) pm, c = 3 697.2(30) pm; 4 : space group P2₁/n (Nr. 14), Z = 4, a = 968.0(4) pm, b = 3 362.5(15) pm, c = 1 051.6(3) pm, β = 109.71(2)°; 5 : space group P2₁/n (Nr. 14), Z = 4, a = 1 040.7(5) pm, b = 1 686.0(5) pm, c = 1 567.7(9) pm, β = 93.88(4)°; 6 : space group Pbca (Nr. 61), Z = 8, a = 1 904.1(8) pm, b = 1 959.9(8) pm, c = 2 309.7(9) pm. 7 : space group P1 (Nr. 2), Z = 2, a = 1 374.4(7) pm, b = 1 476.0(8) pm, c = 1 653.2(9) pm, α = 83.87(4)°, β = 88.76(4)°, γ = 88.28(4)°).     

Beiträge zur Chemie des Phosphors. 245 [1], LiP7(BNEt2)2 und P7(BNEt2)4Cl: Zwei neuartige polycyclische Boraphosphane

Contributions to the Chemistry of Phosphorus. 245, LiP₇(BNEt₂)₂ and P₇(BNEt₂)₄Cl: Two Novel Polycyclic Boraphosphanes The directed synthesis of a noval tetracyclic heteropolyphosphane skeleton from a tricyclophosphane has been achieved by condensation of Li₃P₇ · 3DME with Cl(Et₂N)B‐B(NEt₂)Cl to the diboranonaphosphanide LiP₇(BNEt₂)₂ ( 1 ). When the reaction proceeds the mixed‐substituted diboranonaphosphane P₇(BNEt₂)₄Cl ( 2 ) is formed. According to their ³¹P NMR spectra 1 and 2 possess a B₂P₇(3) skeleton analogous to that of the hydrocarbon deltacyclane. Additional weak signals in the ³¹P NMR spectrum of 2 indicate that also small amounts of the symmetrically substituted diborane(4) P₁₄B₆(NEt₂)₆ ( 3 ) are formed.     

Präparation,Kristallstruktur und thermisches Verhalten der Quecksilber(I)phosphate α-(Hg2)3(PO4)2, β-(Hg2)3(PO4)2 und (Hg2)2P2O7

Contributions on Crystal Structures and Thermal Behaviour of Anhydrous Phosphates. XXIII. Preparation, Crystal Structure, and Thermal Behaviour of the Mercury(I) Phosphates α-(Hg₂)₃(PO₄)₂, β-(Hg₂)₃(PO₄)₂, and (Hg₂)₂P₂O₇ Light-yellow single crystals of (Hg₂)₂P₂O₇ have been obtained via chemical vapour transport in a temperature gradient (500 °C → 450 °C, 23 d) using Hg₂Cl₂ as transport agent. Characteristic feature of the crystal structure (P2/n, Z = 2, a = 9,186(1), b = 4,902(1), c = 9,484(1) Å, β = 98,82(2)°, 1228 independent of 5004 reflections, R(F) = 0,066 for 61 variables, 7 atoms in the asymmetric unit) are Hg₂²⁺-units with d(Hg1–Hg1) = 2,508 Å and d(Hg2–Hg2) = 2,519 Å. The dumbbells Hg₂²⁺ are coordinated by oxygen, thus forming polyhedra [(Hg1₂)O₄] and [(Hg2₂)O₆]. These polyhedra share some oxygen atoms. In addition they are linked by the diphosphate anion P₂O₇^4– (ecliptic conformation; ∠(P,O,P) = 129°) to built up the 3-dimensional structure. Under hydrothermal conditions (T = 400 °C) orange single crystals of the mercury(I) orthophosphates α-(Hg₂)₃(PO₄)₂ and β-(Hg₂)₃(PO₄)₂ have been obtained from (Hg₂)₂P₂O₇ and H₃PO₄ (c = 1%). The crystal structures of both modifications have been refined from X-ray single crystal data [α-form (β-form): P2₁/c (P2₁/n), Z = 2 (2), a = 8,576(3) (7,869(3)), b = 4,956(1) (8,059(3)), c = 15,436(3) (9,217(4)) Å, β = 128,16(3) (108,76(4))°, 1218 (1602) independent reflections of 4339 (6358) reflections, R(F) = 0,039 (0,048) for 74 (74) variables, 8 (8) atoms in the asymmetric unit]. In the structure of α-(Hg₂)₃(PO₄)₂ three crystallographically independent mercury atoms, located in two independent dumbbells, are coordinated by three oxygen atoms each. Thus, [(Hg₂)O₆] dimers with a strongly distorted tetrahedral coordination of all mercury atoms are formed. Such dimers are present besides [(Hg₂)O₅]-polyhedra in the less dense crystal structure of β-(Hg₂)₃(PO₄)₂ (d(Hg–Hg) = 2,518 Å). The mercury(I) phosphates are thermally labile and disproportionate between 200 °C (β-(Hg₂)₃(PO₄)₂) and 480 °C (α-(Hg₂)₃(PO₄)₂) to elemental mercury and the corresponding mercury(II) phosphate.     

Zur Kenntnis eines Barium-Kupfer-Orthoarsenats: BaCu2(AsO4)2

On the Crystal Structure of Barium-Copper-Orthoarsenate BaCu₂(AsO₄)₂ Single crystals of BaCu₂(AsO₄)₂ were prepared above 1 000°C by CO₂-LASER technique and investigated by X-ray structure determination. The light blue crystals show monoclinic symmetry, space group C? P2₁/n, a = 4.752; b = 8.506; c = 8.945 Å; β = 93.49°, Z = 2. BaCu₂(AsO₄)₂ represents a hitherto unknown structure type with Cu²⁺ in trigonal bipyramidal coordination. Ba²⁺ shows an 8 + 2 surrounding by O^2? and As⁵⁺ is tetrahedrally coordinated. The crystal structure is discussed with respect to related orthophosphates and vanadates.     

Cs[Er10(C2)2]I18 und [Er10(C2)2]Br18: zwei neue Beispiele für „reduzierte”︁ Halogenide der Lanthanide mit isolierten [M10(C2)2]-Clustern

Cs[Er₁₀(C₂)₂]I₁₈ and [Er₁₀(C₂)₂]Br₁₈: Two New Examples for Reduced Halides of the Lanthanides with Isolated [M₁₀(C₂)₂] Clusters Cs[Er₁₀(C₂)₂]I₁₈ is obtained from the reaction of ErI₃ with caesium and carbon in sealed tantalum containers at 700°C and [Er₁₀(C₂)₂]Br₁₈ through the metallothermic reduction of ErBr₃ with rubidium in the presence of carbon at 750°C in sealed niobium containers. The crystal structures {Cs[Er₁₀(C₂)₂]I₁₈: triclinic, P1 ; a = 1 105.2(8) pm, b = 1 112.0(7) pm; c = 1 122.9(8) pm; α = 66.91(3)°, β = 87.14(3)°; γ = 60.80(3)°; Z = 1; R = 0.049, R_w = 0.043; [Er₁₀(C₂)₂]Br₁₈: monoclinic, P2₁/n, a = 971.8(6) pm, b = 1 623.4(9) pm, c = 1 163.8(6) pm, β = 104.00(6)°; Z = 2; R = 0.077, R_w = 0.057} contain isolated dimeric [Er₁₀(C₂)₂] clusters. Due to the inclusion of C₂ units, the octahedra are elongated in the direction of the pseudo C₄ axis. The connecting edges of the two octahedra are exceptionally short (316.7 pm and 314.8 pm respectively). The dimeric units are connected via X^i?a and X^a?i (X = Br, I) bridges according to [Er₁₀(C₂)₂XX]X. Cs⁺ is surrounded by a cuboctahedron of iodide ions in Cs[Er₁₀(C₂)₂]I₁₈.     

(Hg2)Hg(OH)2(ClO4)2: Das erste gemischtvalente Quecksilberperchlorat

(Hg₂)Hg(OH)₂(ClO₄)₂: The First Mixed Valent Mercury Perchlorate Colorless single crystals of (Hg₂)Hg(OH)₂(ClO₄)₂ (C2/c, Z = 4, a = 1847.7(5), b = 490.8(1), c = 1086.2(3) pm, β = 93.80(2)°, R_all = 0.0610) were obtained as a side product during the dehydration of Hg₂(ClO₄)₂ · 2H₂O. The crystal structure consists of infinite zig‐zag chains {_∞¹[(Hg₂)_1/2(OH)Hg_1/2]⁺}₂ which are separated by the ClO₄^— ions.     

Synthese und Kristallstrukturen von [Cu4(As4Ph4)2(PRR′2)4], [Cu14(AsPh)6(SCN)2(PEt2Ph)8], [Cu14(AsPh)6Cl2(PRR′2)8], [Cu12(AsPh)6(PPh3)6], [Cu10(AsPh)4Cl2(PMe3)8], [Cu12(AsSiMe3)6(PRR′2)6] und [Cu8(AsSiMe3)4(PtBu3)4] (R,R′ = organische Gruppen)

Syntheses and Crystal Structures of [Cu₄(As₄Ph₄)₂(PRR′₂)₄], [Cu₁₄(AsPh)₆(SCN)₂(PEt₂Ph)₈], [Cu₁₄(AsPh)₆Cl₂(PRR′₂)₈], [Cu₁₂(AsPh)₆(PPh₃)₆], [Cu₁₀(AsPh)₄Cl₂(PMe₃)₈], [Cu₁₂(AsSiMe₃)₆(PRR′₂)₆], and [Cu₈(AsSiMe₃)₄(P^tBu₃)₄] (R, R′ = Organic Groups) Through the reaction of CuSCN with AsPh(SiMe₃)₂ in the presence of tertiary phosphines the compounds [Cu₄(As₄Ph₄)₂(PRR′₂)₄] ( 1 – 3 ) ( 1 : R = R′ = ⁿPr, 2 : R = R′ = Et; 3 : R = Me, R′ = ⁿPr) and [Cu₁₄(AsPh)₆(SCN)₂(PEt₂Ph)₈] ( 4 ) can be synthesised. Using CuCl instead of CuSCN results to the cluster complexes [Cu₁₄(AsPh)₆Cl₂(PRR′₂)₈] ( 5–6 ) ( 5 : R = R′ = Et; 6 : R = Me, R′ = ⁿPr), [Cu₁₂(AsPh)₆(PPh₃)₆] ( 7 ) and [Cu₁₀(AsPh)₄Cl₂(PMe₃)₈] ( 8 ). Through reactions of CuOAc with As(SiMe₃)₃ in the presence of tertiary phosphines the compounds [Cu₁₂(AsSiMe₃)₆(PRR′₂)₆] ( 9 – 11 ) ( 9 : R = R′ = Et; 10 : R = Ph, R′ = Et; 11 : R = Et, R′ = Ph) and [Cu₈(AsSiMe₃)₄(P^tBu₃)₄] ( 12 ) can be obtained. In each case the products were characterised by single‐crystal‐X‐ray‐structure‐analyses. As the main structure element 1 – 3 each have two As₄Ph₄^2–‐chains as ligands. In contrast 4 – 12 contain discrete AsR^2–ligands.     

Triethylphosphanimin-Komplexe der Acetate von Kupfer(II) und Zink. Kristallstrukturen von [Zn(O2C–CH3)2(HNPEt3)], [Cu5(O2C–CH3)10(HNPEt3)2] und [Cu(O2C–CH3)2(HNPEt3)2]

Triethylphosphanimine Complexes of the Acetates of Copper(II) and Zinc. Crystal Structures of [Zn(O₂C–CH₃)₂(HNPEt₃)], [Cu₅(O₂C–CH₃)₁₀(HNPEt₃)₂], and [Cu(O₂C–CH₃)₂(HNPEt₃)₂] The title compounds originate from the anhydrous acetates of zinc and copper(II) with trimethylsilyl-triethylphosphanimine, Me₃SiNPEt₃, in the presence of water in dichloromethane. They form colourless ( 1 ), bluish-green ( 2 ), and blue ( 3 ), respectively, single crystals, which were characterized by IR spectroscopy and by crystal structure analyses. [Zn(O₂C–CH₃)₂(HNPEt₃)] ( 1 ): Space group P 4 2₁c, Z = 8, lattice dimensions at –83 °C: a = b = 1709.6(2), c = 982.4(1) pm, R = 0.0551. 1 has a polymeric chain structure in which the zinc atoms are μ₂-bridged via the oxygen atoms of one of the two acetato groups, while the second acetato group and the phosphanimine are bonded terminally. [Cu₅(O₂C–CH₃)₁₀(HNPEt₃)₂]( 2 · 4 CH₂Cl₂): Space group P2₁/c, Z = 8, lattice dimensions at –80 °C: a = 1761.18(13), b = 4074.5(2), c = 1733.34(15) pm, β = 91.383(10)°, R = 0.0413. 2 consists of the two structural units [Cu₂(O₂C–CH₃)₄] and [Cu₃(O₂C–CH₃)₆(HNPEt₃)₂], which are connected via two of the acetato groups of the Cu₃-unit along the crystallographic a-axis to form three crystallographically independent polymeric strands. [Cu(O₂C–CH₃)₂(HNPEt₃)₂] ( 3 ): Space group P2₁/n, Z = 2, lattice dimensions at 20 °C: a = 695.49(8), b = 1217.85(10), c = 1380.05(7) pm, β = 96.451(7)°, R = 0.0291. 3 forms monomeric, centrosymmetric molecules with a square planar environment at the Cu atoms.     

Neue Untersuchungen zum Reaktionsverhalten von Triorganylcyclotriphosphanen. Die Kristallstrukturen von [(PPh3)2Pt(PtBu)3], [(PPh3)2Pd(PtBu)2], [(CO)4Cr{(PiPr)3}2], [RhCl(PPh3)(PtBu)3], [(NiCO)6(μ2-CO)3{(PtBu)2}2] und [(CpFeCO)2(μ-CO)(μ-PHtBu)]+ · [FeCl3(thf)]–

New Research of Reaction Behaviour of Triorganylcyclotriphosphines. The Crystal Structures of [(PPh₃)₂Pt(P^tBu)₃], [(PPh₃)₂Pd(P^tBu)₂], [(CO)₄Cr{(PⁱPr)₃}₂], [RhCl(PPh₃)(P^tBu)₃], [(NiCO)₆(μ₂-CO)₃{(P^tBu)₂}₂], and [(CpFeCO)₂(μ-CO)(μ-PH^tBu)]⁺ · [FeCl₃(thf)]^– By the reaction of triorganylcyclotriphosphines with transition metal complexes single- and polynuclear compounds are formed, in which the cyclophosphines are bonded in different ways to the metal, the ring either preserving structure or under going ring opening. Depending on the reaction conditions the following compounds can be characterized: [(PPh₃)₂Pt(P^tBu)₃] ( 1 ), [(PPh₃)₂Pd(P^tBu)₂] ( 2 ), [(CO)₄Cr{(PⁱPr)₃}₂] ( 3 ), [RhCl(PPh₃)(P^tBu)₃] ( 4 ), [(NiCO)₆(μ₂-CO)₃{(P^tBu)₂}₂] ( 5 ) and [(CpFeCO)₂(μ-CO)(μ-PH^tBu)]⁺ · [FeCl₃(thf)]^– ( 6 ). The structures of 1 – 6 were obtained by X-ray single crystal structure analysis ( 1 : space group P2₁/n (No. 14), Z = 4, a = 1279.6(3) pm, b = 1733.1(4) pm, c = 2079.1(4) pm, β = 90.20(3)°; 2 : space group P2₁/c (No. 14), Z = 4, a = 1053.3(2) pm, b = 2085.2(4) pm, c = 1855.7(4) pm, β = 98.77(3)°; 3 : space group P 1 (No. 2), Z = 2, a = 1022.6(2) pm, b = 1026.4(2) pm, c = 1706.0(3) pm, α = 82.36(3)°, β = 86.10(3)°, γ = 64.40(3)°; 4 : space group P 1 (No. 2), Z = 2, a = 980.2(2) pm, b = 1309.5(3) pm, c = 1573.4(3) pm, α = 99.09(3)°, β = 99.46(3)°, γ= 111.87(3)°; 5 : space group P2₁/c (No. 14), Z = 4, a = 1804.0(5) pm, b = 2261.2(6) pm, c = 1830.1(7) pm, β = 96.99(3)°; 6 : space group P2₁/c (No. 14), Z = 4, a = 943.2(3) pm, b = 2510.6(7) pm, c = 1325.1(6) pm, β = 98.21(3)°).     

Kristallstruktur des Isothiocyanato‐Komplexes [Ph3PNH2(OEt2)][Sm(NCS)4(DME)2]

Crystal Structure of the Isothiocyanato Complex [Ph₃PNH₂(OEt₂)][Sm(NCS)₄(DME)₂] Colourless single crystals of [Ph₃PNH₂(OEt₂)][Sm(NCS)₄(DME)₂] ( 1 ) have been obtained besides of Ph₃PS from the reaction of the homoleptic phosphorane iminato complex [Sm(NPPh₃)₃]₂ with carbon disulfide in THF solution, followed by recrystallisation from DME/Et₂O. According to the crystal structure analysis 1 consists of [Ph₃PNH₂]⁺ cations with the diethylether molecule forming a N–H…O hydrogen bridge, and anions [Sm(NCS)₄(DME)₂]^–. Sm³⁺ realizes coordination number eight by four nitrogen atoms of the isothiocyanato ions and by four oxygen atoms of the DME chelates. 1 : Space group P 1, Z = 4, lattice dimensions at 193 K: a = 919.0(1), b = 1965.2(2), c = 2401.3(2) pm, α = 96.748(11)°, β = 94.827(10)°, γ = 91.720(11)°, R = 0.029.     

Neue Silber‐Tellurid Cluster stabilisiert mit zweizähnigen Phosphanen: Synthese und Struktur von {[Ag5(TePh)6(Ph2P(CH2)2PPh3)](Ph2P(CH2)2PPh2)}∞, [Ag18Te(TePh)15(Ph2P(CH2)3PPh2)3Cl] und [Ag38Te13(TetBu)12(Ph2P(CH2)2PPh2)3]

Novel Silver‐Telluride Clusters Stabilised with Bidentate Phosphine Ligands: Synthesis and Structure of {[Ag₅(TePh)₆(Ph₂P(CH₂)₂PPh₃)](Ph₂P(CH₂)₂PPh₂)}_∞, [Ag₁₈Te(TePh)₁₅(Ph₂P(CH₂)₃PPh₂)₃Cl], and [Ag₃₈Te₁₃(Te t Bu)₁₂(Ph₂P(CH₂)₂PPh₂)₃] Bidentate phosphine ligands have been found effective to stabilise polynuclear cores containing silver and chalcogenide ligands. They can act as intra and intermolecular bridges between the silver centres. The clusters {[Ag₅(TePh)₆(Ph₂P(CH₂)₂PPh₃)](Ph₂P(CH₂)₂PPh₂)}_∞ ( 1 ), [Ag₁₈Te(TePh)₁₅(Ph₂P(CH₂)₃PPh₂)₃Cl] ( 2 ), and [Ag₃₈Te₁₃(TetBu)₁₂(Ph₂P(CH₂)₂PPh₂)₃] ( 3 ) have been prepared and their molecular structure determined. Compound 2 and 3 are molecular structures with separated cluster cores while 1 forms a polymeric chain bridged by phosphine ligands. ( 1 : space group P2₁/c (No. 14), Z = 4, a = 3518,1(7) pm, b = 2260,6(5) pm, c = 3522,1(7) pm, β = 119,19(3)°; 2 : space group R3 (No. 148), Z = 6, a = b = 3059,4(4) pm, c = 5278,8(9) pm; 3: space group Pccn (No. 56), Z = 4, a = 3613,0(9) pm, b = 3608,6(7) pm, c = 2153,5(8) pm)     

Lifetime of the He2(e), He2(d) and He2(f) states

Starting from the He₂(a) state absorption and induced fluorescence experiments were performed using a narrow band dye laser. The saturation intensity for the He₂(e)←He₂(a) transition yields a radiative lifetime of τ=(67±10) ns. Time resolved measurements of the laser induced fluorescence yield the radiative lifetimes for the states He₂(e): (57±10) ns, He₂(d): (25±5) ns and He₂(f): (19±5) ns. From the time integrated fluorescence data the collisional quenching rates between the above states were determined.     

Sterisch abgeschirmte Nitridokomplexe von Molybdän und Wolfram Die Kristallstrukturen von [MoN(NPh2)3] und [W4N4(NPh2)6(OnC4H9)2]

Stericly Shielded Nitrido Complexes of Molybdenum and Tungsten. The Crystal Structures of [MoN(NPh₂)₃] and [W₄N₄(NPh₂)₆(OⁿC₄H₉)₂] The reactions of MoNCl₃ and WNCl₃, respectively, with lithium diphenylamide in tetrahydrofurane produce the monomeric nitrido complexes MN(NPh₂)₃ with CN = 4 at the metal atoms. In the presence of lithium-n-butyl LiNPh₂ and WNCl₃ also form the tetrameric nitrido complex [W₄N₄(NPh₂)₆(OⁿC₄H₉)₂] which contains W^V and W^VI. The compounds are characterized by their i.r. spectra, by X-ray structural analysis, and, partially, by ¹H and ¹³C n.m.r. spectroscopy. MoN(NPh₂)₃: Space group P1 , Z = 2, 4060 observed independent reflexions, R = 0.031. Lattice dimensions at 20°C: a = 956.2(4) pm, b = 1 015.9(2) pm, c = 1 598.1(3) pm; α = 79.06(2)°, β = 85.67(3)°, γ = 82.57(3)°. The compound forms monomeric molecules with Mo?N bond lengths of 163.4 pm and mean Mo? NPh₂ distances of 199.2 pm. [W₄N₄(NPh₂)₆(OⁿC₄H₉)₂]: Space group P2₁/n, Z = 2, 1903 observed independent reflexions, R=0.039. Lattice parameters at 19°C: a = 1582.2(3) pm, b = 1182.4(2) pm, c = 2053.3(4) pm; β = 103.77(2)°. The compound forms centrosymmetric molecules, in which the central W–W dumb-bell (bond length 253.5 pm) is linked by the nitrido ligands of two WN₂(NPh₂)₂=units in a T shaped order of the N-atoms.     

Neue Phosphor-verbrückte Übergangsmetallcarbonyl-Komplexe Die Kristallstrukturen von [Re2(CO)7(PtBu)3], [Co4(CO)10(PtBu)2], [Ir4(CO)6(PtBu)6] und [Ni4(CO)10(PiPr)6]

New Phosphorus-bridged Transition Metal Carbonyl Complexes. The Crystal Structures of [Re₂(CO)₇(P^tBu)₃], [Co₄(CO)₁₀(P^tBu)₂], [Ir₄(CO)₆(P^tBu)₆], and [Ni₄(CO)₁₀(PⁱPr)₆], (P^tBu)₃ reacts with [Mn₂(CO)₁₀], [Re₂(CO)₁₀], [Co₂(CO)₈] and [Ir₄(CO)₁₂] to form the multinuclear complexes [M₂(CO)₇(P^tBu)₃] (M = Re ( 1 ), Mn ( 5 )), [Co₄(CO)₁₀(P^tBu)₂] ( 2 ) and [Ir₄(CO)₆(P^tBu)₆] ( 3 ). The reaction of (PⁱPr)₃ with [Ni(CO)₄] leads to the tetranuclear cluster [Ni₄(CO)₁₀(PⁱPr)₆] ( 4 ). The complex structures were obtained by X-ray single crystal structure analysis: ( 1 : space group P1 (Nr. 2), Z = 2, a = 917.8(3) pm, b = 926.4(3) pm, c = 1 705.6(7) pm, α = 79.75(3)°, β = 85.21(3)°, γ = 66.33(2)°; 2 : space group C2/c (Nr. 15), Z = 4, a = 1 347.7(6) pm, b = 1 032.0(3) pm, c = 1 935.6(8) pm, β = 105.67(2)°; 3 : space group P1 (Nr. 2), Z = 4, a = 1 096.7(4)pm, b = 1 889.8(10)pm, c = 2 485.1(12) pm, α = 75.79(3)°, β = 84.29(3)°, γ = 74.96(3)°; 4 : space group P2₁/c (Nr. 14), Z = 4, a = 2 002.8(5) pm, b = 1 137.2(8) pm, c = 1 872.5(5) pm, β = 95.52(2)°).