Über Perowskite Ba2BBTeVIO6

On Perovskites Ba₂B B Te^VIO₆ Compounds of composition Ba₂BBTe^VIO₆ with B^I = Li, Na; B^III = La, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Yb, Y, In, Sc crystallize in a cubic 1:1 ordered perovskite structure. The vibrational spectroscopic investigations show, that more species of TeO₆ octahedra are present in the lattice.     

Über geordnete Perowskite mit Kationenfehlstellen. X. Verbindungen vom Typ ABB□1/4MVIO6 ≙ ABIIB□MO24 mit AII,BII = Ba,Sr, Ca und MVI = U,W

On Ordered Perovskites with Cationic Vacancies. X. Compounds of Type A B B □_1/4M^VIO₆ ? A B^IIB □M O₂₄ with A^II, B^II = Ba, Sr, Ca and M^VI = U, W Perovskites of type Ba₈B^IIB₂^III□UO₂₄ show polymorphic phase transformations of order disorder type. An 1:1 ordered orthorhombic HT form is transformed into a higher ordered LT modification with a fourfold cell content (four formula units Ba₈B^IIB□U₄O₂₄), compared to cubic 1:1 ordered perovskites A₂BMO₆. In the series Ba₈BaB□W₄O₂₄ and Sr₈SrB□W₄O₂₄ different ordering phenomena are observed. In comparison with 1:1 ordered cubic perovskites A₂BMO₆, the cell contains eight formula units AB^IIB□W₄O₂₄. The higher ordered cells with U^VI and W^VI are face centered, which has its origin in an ordering of cationic vacancies.     

19F-NMR-spektroskopischer Nachweis und Berechnung der statistischen Bildung der gemischten Clusteranionen [(Mo6BrCl)F]2−, n = 0 – 8

¹⁹F NMR Spectroscopic Evidence and Calculation of the Statistical Formation of Mixed Cluster Anions [(Mo₆Br Cl )F ]^2?, n = 0 – 8 The complete system of the innersphere mixed clusters (Mo₆BrCl)⁴⁺ is formed by exchange of innersphere bound Clⁱ against outersphere bound Br^a on tempering the solid [(Mo₆Cl)Br] at 500°C for 16 h. After conversion with conc. HCl into (H₃O)₂[(Mo₆BrCl)Cl] and precipitation of the outer Cl^a with AgBF₄ in ethanol, treatment with tetrabutylammonium(TBA)fluoride yields (TBA)₂ [(Mo₆BrCl)F], a mixture of 22 different species. According to the sets of chemical equivalent fluorine atoms in total 55 ¹⁹F nmr signals are expected, which are really observed in the high resolution 1D-¹⁹F-nmr spectrum. Using increments of chemical shifts, peak intensities and multiplet structures as well as the 2D-¹⁹F/¹⁹F-COSY spectrum the complete and unambiguous assignment of all resonances is achieved. From the measured integral intensities the distribution of the different compounds is determined, revealing statistical formation of the geometrical isomers.     

Über geordnete Perowskite mit Kationenfehlstellen. XI. Verbindungen vom Typ ABB□1/4WVIO6 ≙ ABIIB□WO24 mit AII,BII = Ba,Sr

On Ordered Perovskites with Cationic Vacancies. XI. Compounds of Type A B B □_1/4W^VIO₆ ? A B^IIB □W O₂₄ with A^II, B^II = Ba, Sr Depending on the ionic radii of the two and three valent cations in the perovskites of type ABB □_1/4W^VIO₆ ?; AB^IIB □WO₂₄ order disorder phenomena are present. The results of the x-ray and vibrational spectroscopic investigations as well as the diffuse reflectance spectra and the visible photoluminescence are reported.     

Über hexagonale Perowskite mit Kationenfehlstellen. XXIV. Rhomboedrische 9 L-Stapelvarianten in den Systemen Ba3W M □ O9−x/2□x/2 mit MV = Nb,Ta

On Hexagonal Perovskites with Cationic Vacancies. XXIV. Rhombohedral 9 L Stacking Polytypes in the Systems Ba₃W M □O_9?x/2□_x?2 with M^V = Nb, Ta In the system Ba₃WNb□O_9?x/2□_x/2 stacking polytypes of rhombohedral 9 L type (sequence (hhc)₃; space group R3 m) can be prepared with ～1/3 ? × ? 2. For x = 2(Ba₃Nb₂□O₈□) two modifications are formed. In the corresponding Ta system the phase with is reduced to a smaller region with x ? 1/3.     

19F-NMR-spektroskopischer Nachweis und statistische Untersuchung zur Bildung der gemischten Clusteranionen [(Mo6ICl)F]2−, n = 0–7, und Darstellung von (TBA)2[(Mo6I)F]

¹⁹F NMR Spectroscopic Evidence and Calculation of the Statistical Formation of Mixed Cluster Anions [(Mo₆I Cl )F ]^2?, n = 0–7, and Preparation of (TBA)₂[(Mo₆I )F ] The octa-μ₃-iodo-hexafluoro-hexamolybdate(2?)ion [(Mo₆I)F]^2? is prepared for the first time. The system of the 21 innersphere mixed clusters (Mo₆ICl)⁴⁺, n = 0–7 is formed by exchange of innersphere bound Clⁱ against outersphere bound I^a on tempering solid [(Mo₆Cl)I] at 400°C. Prolonged tempering leads to increasing average n values of the mixture, which is converted into the tetrabutylammonium salt (TBA)₂[(Mo₆ICl)F]. Using increments of chemical shifts and integral peak intensities the 54 ¹⁹F-nmr signals of the 21 species (compound n = 8 is absent) are assigned and confirmed by the 2 D-¹⁹F/¹⁹F-COSY spectrum. From the measured intensities the distribution of the different compounds is determined and proves significant deviation from statistical occupation, revealing the preference of isomers with iodine atoms occupying edges of the innersphere cube and discrimination of those sharing diagonals of the faces. Moreover all compounds with n = 3 and 4 are present overaverage in comparison to the others.     

Zur Kristallstruktur von Ba2ZnO3

On the Crystal Structure of Ba₂ZnO₃ Single crystals of Ba₂ZnO₃ were prepared by solid state reaction. It crystallizes monoclinic: space group C ? C12/c1; a = 5.833; b = 11.376; c = 12.585 Å; β = 93.63°; Z = 8. The crystal structure is characterised by [ZnO₃] chains along [100]. They are connected by Ba²⁺ in seven fold oxygen coordination.     

Schwingungsspektren und Kraftkonstanten der Übergangsreihe O2PF—S2PF— S2P(CH3)

Vibration spectra and force constants of the series O₂PF — S₂PF — S₂P(CH₃). The vibrational spectra of OSPF, S₂PF, S₂PF(CH₃) and S₂P(CN) are reported and discussed with O₂PF and S₂P(CH₃). On the basis of a simplified valence-force-field the force constants are calculated and the bonding relations are discussed. In the ions, f PF is lower than in corresponding molecules. The ionic charge is distributed over nearly all atoms of the ions.     

Über das Auftreten von Monoselenan- und Monotelluran-disulfandiphosphonat bei der Umsetzung von SPO mit Seleno- und Telluropolythionaten

On the Formation of Monoselenane and Monotellurane Disulphane-diphosphonate by the Reaction of SPO with Seleno and Telluropolythionates In the reaction of seleno- and telluropolythionates with SPO, SeS₂P₂O and TeS₂P₂O are formed and are described for the first time. Polysulfphane-diphosphonates, -disulphonates and -phosphonsulphonates occur as side and consecutive products. By evaluation of radiochemical double labelling with the nuclide pairs ³⁵S? ³²P and ³⁵S? ⁷⁵Se, it is possible to identify the products formed and obtain information about the reaction mechanism.     

Die Photolumineszenz der dreiwertigen Seltenen Erden in den Perowskitstapelvarianten Ba2La2−xSE MgW2□O12, Ba6Y2−xSEW3□O18 und Sr8SrGd2−x SEW4□O24

Photoluminescence of Trivalent Rare Earths in Perovskite Stacking Polytypes Ba₂La_2?x RE MgW₂□O₁₂, Ba₆Y_2?x RE W₃□O₁₈, and Sr₈SrGd_2?xRE W₄□O₂₄ Rhombohedral 12 L stacking polytypes Ba₂La_2?xREMgW₂□O₁₂ show with RE³⁺ = Pr, Sm, Eu, Tb, Dy, Ho, Er, Tm; the 18 L stacking polytypes Ba₆Y_2?xREW₃□O₁₈ and the polymorphic perovskites Sr₈SrGd_2?xREW₄□O₂₄ with RE³⁺ = Sm, Eu, Dy, Ho, Er visible photoluminescence. The concentration dependence and the influence of the coordination number of the rare earth are reported.     

Darstellung,Kristallstruktur und Schwingungsspektren von (n-Bu4N)2[(Mo6I)(NCS)]

Synthesis, Crystal Structure, and Vibrational Spectra of (n-Bu₄N)₂[(Mo₆I)(NCS)] By treatment of [(Mo₆I)I]^2– with (SCN)₂ in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(Mo₆I)(NCS)]^2– is formed. The X-ray structure determination of (n-Bu₄N)₂[(Mo₆I)(NCS)] · 2 Me₂CO (monoclinic, space group P2₁/c, a = 13.168(5), b = 11.964(5), c = 24.636(5) Å, β = 104.960(5)°, Z = 2) shows, that the thiocyanate groups are coordinated exclusively via N atoms with Mo–N bond lengths of 2.141–2.150 Å, Mo–N–C angles of 166–178° and N–C–S-angles of 174–180°. The vibrational spectra exhibit characteristic innerligand vibrations at 2073–2054 (ν_CN), 846–844 (ν_CS) and 480–462 cm^–1 (δ_NCS).     

Dibrommethylsulfoniumsalze – Darstellung und Kristallstruktur [1]

Dibromomethylsulfoniumsalts — Preparation and Crystal Structure The salts CH₃SBrA^? (A^? = SbCl, AsF) were prepared by various routes and characterized by their Ramanspectra. CH₃SBrAsF crystallized in the monoclinic space group P2₁/c with a = 770,5(4) pm, b = 942,4(12) pm, c = 1329,3(14) pm, β = 100,28(6)°, Z = 4. Distances and bond angles in the cation are as expected.     

Dicyanmethanido- und Cyanamido-oxoanionen. Untersuchungen zum sauerstoffanalogen Charakter der C(CN)2- und NCN-Gruppen

The equivalence of the C(CN)₂- and the NCN-groups with oxygen in the series of homologous ions C(CN), N(CN), OCN^? and NOC(CN), NO causes us to postulate a more general value of this relation. Arguments for the formulation of a pseudochalkogen series C(CN)₂? NCN? O are discussed. Synthesis, structure and reactivity of some dicyanmethanido- and cyanamido-oxoanions RCOY^?, CO₂Y^2?, COY, NOY^?, NO₂Y^?, PO₃Y^3?, PO₂Y and SO₂Y^2? are described. (Y ? C(CN)₂, NCN.) The preparation of some triorganoleadacyles is reported.     

Interactions Magnetiques dans quelques Ferrites Oxyfluores a Structure Spinelle de Formule ZnxMFe2−xO4–xFx (M ? Fe,Co, Ni)

Magnetic interactions in some oxyfluoroferrites of spinel structure with the formula Zn_xMe_2?xO_4?xFx (M = Fe, Co, Ni) Whereas the ferromagnetic spin arrangement of the B-cations is not modified by the Zn²⁺?Fe³⁺ substitution in the ZnFe[Fe₂₊Fe³⁺]O_4?xF_x (0 ≤ x ≤ 0,50) spinel, this same substitution leads to a spin canting in the ZnFe[Co₂₊Fe³⁺]O_4?xF_x and ZnFe[Ni₂₊Fe³⁺]O_4?xF_x (0 ≤ x ≤ 0,80) simples. The difference in the magnetic behaviors with regard to the AB and BB interactions can be explained on the basis of the magnetic exchange theory.     

Darstellung,Kristallstrukturen und Schwingungsspektren von [(Mo6X)Y]2–; Xi = Cl,Br; Ya = NO3, NO2

Synthesis, Crystal Structures, and Vibrational Spectra of [(Mo₆X)Y]^2–; Xⁱ = Cl, Br; Y^a = NO₃, NO₂ By treatment of [(Mo₆X)Y]^2–; Xⁱ = Y^a = Cl, Br with AgNO₃ or AgNO₂ by strictly exclusion of oxygene in acetone the hexanitrato and hexanitrito cluster anions [(Mo₆X)Y]^2–, Y^a = NO₂, NO₃ are formed. X-ray structure determinations of (Ph₄As)₂[(Mo₆Cl)(NO₃)] · 2 Me₂CO ( 1 ) (monoclinic, space group P2₁/n, a = 12.696(3), b = 21.526(1), c = 14.275(5) Å, β = 115.02(2)°, Z = 2), (n-Bu₄N)₂[(Mo₆Br)(NO₃)] · 2 CH₂Cl₂ ( 2 ) (monoclinic, space group P2₁/n, a = 14.390(5), b = 11.216(5), c = 21.179(5)Å, β = 96.475(5)°, Z = 2) and (Ph₄P)₂[(Mo₆Cl)(NO₂)] (3) (monoclinic, space group P2₁/n, a = 11.823(5), b = 13.415(5), c = 19.286(5) Å, β = 105.090(5)°, Z = 2) reveal the coordination of the ligands via O atoms with (Mo–O) bond lengths of 2.11–2.13 Å, and (MoON) angles of 122–131°. The vibrational spectra of the nitrato compounds show the typical innerligand vibrations ν_as(NO₂) (∼ 1500), ν_s(NO₂) (∼ 1270) and ν(NO) (∼ 980 cm^–1). The stretching vibrations ν(N=O) at 1460–1490 cm^–1 and ν(N–O) in the range of 950–1000 cm^–1 are characteristic for nitrito ligands coordinated via O atoms.     

Silaheterocyklen. III. Erzeugung und Reaktivität von Di-tbutyl-Neopentylsilaethen,BuSiCHCH2But

Silaheterocycles. III. Synthesis and Reactivity of Di-^tbutylneopentylsilaethene, Bu Si?CHCH₂Bu^t The three di-^tbutylvinylsilanes BuSi(X)CH?CH₂ (X = H 5 , X = F 9 , X = Cl 22 ) are prepared by the reaction of their SiCl precursors with vinyl lithium. In the treatment with LiBu^t the first step is the generation of the α-lithio compound BuSi(X)CH(Li)CH₂Bu^t, the following reactions are governed by the nature of the substituent X and the reaction conditions (solvent, concentration, temperature). For X = H 2,3-LiH elimination leads to BuSi(H)CH?CHBu^t ( 7 ), with X = F or Cl Si?C formation by 1,2-LiX elimination competes with intermolecular Si-C-coupling producing BuSi(H)CH(SiBuCH?CHBu^t)CH₂Bu^t ( 13 ) as the main product. BuSi?CHCH₂Bu^t ( 1 ) probably coordinates to LiBu^t and reacts to yield BuSiCH?CHBu^t ( 3 ) and 7 , forms tetrabutyl-dineopentyl-1,3-disilacyclobutane 2 by cyclodimerization and 13 by addition of BuSi(X)CH(Li)CH₂Bu^t.     

Darstellung,Schwingungsspektrum und Kristallstruktur von (n‐Bu4N)2[(W6Cl)F] · 2 CH2Cl2 und 19F‐NMR‐spektroskopischer Nachweis der gemischten Clusteranionen [(W6Cl)FCl]2–, n = 1–6

Synthesis, Vibrational Spectra, and Crystal Structure of ( n ‐Bu₄N)₂[(W₆Cl )F ] · 2 CH₂Cl₂ and ¹⁹F NMR Spectroscopic Evidence of the Mixed Cluster Anions [(W₆Cl )F Cl ]^2–, n = 1–6 The reaction of (n‐Bu₄N)₂[(W₆Cl)Cl] with CF₃COOH in dichloromethane gives intermediately a mixture of the cluster anions [(W₆Cl)(CF₃COO)Cl]^2–, n = 1–6. By treatment with NH₄F the outer sphere coordinated trifluoracetato ligands are easily substituted and the components of the series [(W₆Cl)FCl], n = 1–6 are formed and characterized by their distinct ¹⁹F NMR chemical shifts. An X‐ray structure determination has been performed on a single crystal of (n‐Bu₄N)₂[(W₆Cl)F] · 2 CH₂Cl₂ (orthorhombic, space group Pbca, a = 15.628(4), b = 17.656(3), c = 20.687(4) Å, Z = 4). The low temperatur IR (60 K) and Raman (20 K) spectra are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are f_d(WW) = 1.89, f_d(WF) = 2.43 and f_d(WCl) = 0.93 mdyn/Å.     

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.     

The crystal structure of tris (ethylenediamine), cobalt(III) hexacyanoferrate(III)dihydrate,Co(C2H8N2)3[Fe(CN)6] · 2H2O

The crystal structure of the title compound has been determined from three dimensional x-ray data obtained by the multiple film method. The space group is P2_l/n and the cell dimensions are: a = 14.90, b = 16.84, c = 8.38 Å; β = 93.5° Z = 4. The structure is formed by discrete Co (en) and Fe(CN) ions, both of which have an octahedral configuration. The Fe(CN) ions are approximately octahedrally surrounded by the Co (en) ions while arrangement of Fe (CN) ions around the Co(en) ions completely differs from an octahedron. The mean Fe? C and Co? C dustances are 1.91 and 2.01 Å, respectively. The water molecules do not play an important role in the structure and all distances between oxygen and other atoms indicate the presence of very weak hydrogen bonds. The salts M (en)₃ Q(CN)₆ · H₂O, where M = Co and Cr and Q = Cr, Mn, Fe and Co, are all isomorphous.     

Über hexagonale Perowskite mit Kationenfehlstellen. XXXI. Die Systeme BaO?Re2O7?MO5 mit MV = Nb,Ta

On Hexagonal Perovskites with Cationic Vacancies. XXXI. Systems BaO? Re₂O₇? M O₅ with M^V = Nb, Ta In the systems BaO? Re₂O₇? MO₅ three quaternary oxides are formed, which belong to the perovskite stacking polytypes with cationic vacancies: Ba₈Re_7/2M□₃O₂₄ (M^V = Nb, Ta; rhombohedral 24 L type; sequence (hhhhchhc)₃; space group R3 m), Ba₄Re_9/8Ta_13/8□_5/4O₁₂ (rhombohedral 12 L type; sequence (hhcc)₃; space group R3 m) and the phases Ba₅BaRe_3/2?xM □O_15?x□_x (M^V = Nb, Ta; variants of a hexagonal 5 L type).