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1.
Preparation and Spectroscopic Characterization of the Cluster Anion [(Mo6Cl )(CF3COO) ]2? On heating of [(Mo6Cl)Cl]2? in dichloromethane with trifluoroacetic acid the new stable cluster anion [(Mo6Cl)(CF3COO)]2? is formed by elimination of HCl. The (Mo6Cl) unit remains unattacked. The 19F nmr spectrum exhibits a downfield shifted singulett as compared to free CF3COO? indicating the equivalence of all trifluoroacetate ligands, which unidentate coordination is deduced from characteristic i. r. frequencies of the carboxyl groups. The most intense i.r. band at 501 cm?1 is assigned to the antisymmetric Mo? Oa vibration, the most intense Raman line at 319 cm?1 to the breathing mode of the Cl cube. 相似文献
2.
Synthesis, Crystal Structures, and Vibrational Spectra of [(Mo6X)Y]2–; Xi = Cl, Br; Ya = NO3, NO2 By treatment of [(Mo6X)Y]2–; Xi = Ya = Cl, Br with AgNO3 or AgNO2 by strictly exclusion of oxygene in acetone the hexanitrato and hexanitrito cluster anions [(Mo6X)Y]2–, Ya = 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 νas(NO2) (∼ 1500), νs(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. 相似文献
3.
Synthesis, Crystal Structures, and Vibrational Spectra of [(Ph3P)2N]2[(W6Cl )I ] · 2 Et2O · 2 CH2Cl2 and [(Ph3P)2N]2[(W6Cl )(NCS) ] · 2 CH2Cl2 By treatment of [(W6Cl)I]2– with (SCN)2 in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(W6Cl)(NCS)]2– is formed. X‐ray structure determinations have been performed on single crystals of [(Ph3P)2N]2[(W6Cl)I] · 2 CH2Cl2 · 2 Et2O ( 1 ) (triclinic, space group P1, a = 10.324(5), b = 14.908(3), c = 17.734(8) Å, α = 112.78(2)°, β = 99.13(3)°, γ = 92.02(3)°, Z = 1) and [(Ph3P)2N]2[(W6Cl)(NCS)] · 2 CH2Cl2 ( 2 ) (triclinic, space group P1, a = 11.115(2), b = 14.839(2), c = 17.036(3) Å, α = 104.46(1)°, β = 105.75(2)°, γ = 110.59(1)°, Z = 1). The thiocyanate ligands of 2 are bound exclusively via N atoms with W–N bond lengths of 2.091–2.107 Å, W–N–C angles of 173.1–176.9° and N–C–S angles of 178.1–179.3°. The vibrational spectra exhibit characteristic innerligand vibrations at 2067–2045 (νCN), 879–867 (νCS) and 490–482 (δNCS). Based on the molekular parameters of the X‐ray determination of 1 the vibrational spectra of the corresponding (n‐Bu4N) salt of 1 are assigned by normal coordinate analysis. The valence force constants are fd(WW) = 1.61, fd(WI) = 1.23 and fd(WCl) = 1.10 mdyn/Å. 相似文献
4.
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 Bra 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 Cla 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. 相似文献
5.
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 Ia 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. 相似文献
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 fd(WW) = 1.89, fd(WF) = 2.43 and fd(WCl) = 0.93 mdyn/Å. 相似文献
7.
Thermal Behaviour and Crystal Structure of YAl3Cl12 We determined the thermodynamic data of YAl3Cl12 ΔH = ?739.9 ± 3 kcal/mol and S = 136.1 ± 4 cal/K · mol by total pressure measurements and ΔH = ?739.1 ± 1.6 kcal/mol by solution calorimetry. Using DTA-investigations we established the phase diagram in the system AlCl3–YCl3. The crystal structure was refined on the basis of single crystal data (P31 12; Z = 3; a = 1 046.8(2); c = 1 562.3(3) pm). 相似文献
8.
Nitride Sulfide Chlorides of the Lanthanides. III. Synthesis and Crystal Structure of Pr5N3S2Cl2 By reacting praseodymium with sulfur, sodium azide and praseodymium trichloride in sealed, evacuated silica tubes (850°C, 7 d), the nitride sulfide chloride Pr5N3S2Cl2 is obtained in case of a 4:2:1:1 molar ratio of the reactants (Pr:S:NaN3:PrCl3). A slight excess of trichloride or the addition of NaCl as a flux supports the yield of brownish red, rod-shaped transparent crystals which prove to be stable against hydrolysis. The crystal structure (monoclinic, C2/m (no. 12), a = 1540.2(1), b = 400.92(3), c = 1656.3(1) pm, β = 101.24(1)°, Z = 4, R = 0.039, Rw = 0.028) was determined by means of X-ray single crystal data. Thus five crystallographically different cations (Pr3+) are present which with three distinct kinds of nitride anions (N3?) build up two types of translationally commensurate chains from interconnected [NPr4] tetrahedra. With an additional edge per “chain-link” in chain I, two single chains [NPr3/3ePr1/1t]3+ (?[NPr2]3+) of cis-edge connected [NPr4] tetrahedra (known from the Sm4N2S3-type structure) are condensed into the double chain [(N1){(Pr1)(2+2)/(2+2)e,e(Pr2)(2+1)/(2+1)e,v}(N2)(Pr3)1/1t]3+ (?[N2Pr3]3+). Chain II consists of two single chains [NPr2/2vPr2/1t] 6+ (?[NPr3]6+) of vertex-connected [NPr4] tetrahedra (known from the Sm3NS3-type structure), which are condensed to the double chain [(N3)(Pr4)2/2e(Pr5)2/2v]3+ (?[NPr2]3+) via an additional edge per “chain-link” too. Both types of chains are bundled along [010] like a closest packing of rods. Four crystallographically different but by X-ray diffraction indistinguishable anions S2? and Cl? hold both cationic double chains together and also adjust the charge balance in a molar ratio of 1 : 1. 相似文献
9.
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 (νCN), 846–844 (νCS) and 480–462 cm–1 (δNCS). 相似文献
10.
Synthesis, Crystal Structures, and Vibrational Spectra of [OsBr(acac)(PPh3)] and [OsBr(acac)(AsPh3)] By reaction of tetrabromoacetylacetonatoosmate(IV) with PPh3 or AsPh3 in ethanol the complexes [OsBr(acac)(PPh3)] ( 1 ) and [OsBr(acac)(AsPh3)] ( 2 ) are formed, which are purified by chromatography on silica gel. X-ray structure determinations of single crystals of ( 1 ) (monoclinic, space group P 21/n, a = 13.035(2), b = 18.2640(14), c = 16.636(3) Å, β = 112.776(14)°, Z = 4) and ( 2 ) (monoclinic, space group P 21/c, a = 13.23(5), b = 18.35(2), c = 16.65(2) Å, β = 112.9(5)°, Z = 4) result in mean bond distances Os–P = 2.413, Os–As = 2.483, Os–Br = 2.488 and Os–O = 2.037 Å. The vibrational spectra (10 K) exhibit the inner ligand vibrations of the acac, PPh3 and AsPh3 groups with nearly constant frequencies and the stretching vibrations of OsP at 499–522, of OsAs at 330–339, of OsBr at 213–214 and of OsO in the range 460–694 cm–1. 相似文献
11.
On Ordered Perovskites with Cationic Vacancies. X. Compounds of Type A B B □1/4MVIO6 ? A BIIB □M O24 with AII, BII = Ba, Sr, Ca and MVI = U, W Perovskites of type Ba8BIIB2III□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 Ba8BIIB□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 ABIIB□W4O24. The higher ordered cells with UVI and WVI are face centered, which has its origin in an ordering of cationic vacancies. 相似文献
12.
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. 相似文献
13.
Andrea Decker Falk Simon Kamal Boubekeur Dieter Fenske Patrick Batail 《无机化学与普通化学杂志》2000,626(1):309-313
Reactions of dry THF/MeCN solutions of Ca[Re6SCl(Cla)6] with silylated derivatives E(SiMe3)2 (E = PhAs, PSiMe3, HN, O, S) and addition of trialkylphosphine PPr3 afford in high yields and at room temperature either the neutral clusters [Re6SX(PPr3)] ( 1 : X = As, 2 : X = P) or the ionic compounds [Re6SX(PPr3)]2+ · [Re6S6Cl8]2– ( 3 : X = NH, 4 : X = O, 5 : X = S). The compounds 1 – 5 were characterised by X‐ray crystal structure analysis. A di‐substitution reaction occurs on the {Re6SCl}4+ cluster core, where the two inner μ3‐chloro ligands Cli are substituted by X (X = As, P, NH, O, S) and all six terminal chloro ligands Cla are exchanged by terminal PPr3‐ligands. 相似文献
14.
S. Kemmler-Sack 《无机化学与普通化学杂志》1981,483(12):126-139
Photoluminescence of Trivalent Rare Earths in Perovskite Stacking Polytypes Ba2La2?x RE MgW2□O12, Ba6Y2?x RE W3□O18, and Sr8SrGd2?xRE W4□O24 Rhombohedral 12 L stacking polytypes Ba2La2?xREMgW2□O12 show with RE3+ = Pr, Sm, Eu, Tb, Dy, Ho, Er, Tm; the 18 L stacking polytypes Ba6Y2?xREW3□O18 and the polymorphic perovskites Sr8SrGd2?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. 相似文献
15.
On Ordered Perovskites with Cationic Vacancies. XI. Compounds of Type A B B □1/4WVIO6 ? A BIIB □W O24 with AII, BII = Ba, Sr Depending on the ionic radii of the two and three valent cations in the perovskites of type ABB □1/4WVIO6 ?; ABIIB □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. 相似文献
16.
On Perovskites A B B WVIO6 Compounds of type ABBWVIO6 can be obtained with AII ? Ba; BI ? Li, Na and BIII ? La, Nd, Sm, Gd, Y, In, Sc just as with AII ? Sr, BI ? Li and BIII ? La, Nd, Sm, Gd, Y, In (all cubic ordered perovskites). For the cubic perovskites Sr2Na0,5La0,5WO6 and Sr2Na0,5Nd0,5WO6 additional superlattice reflections are observed (a ∽ 16.4 Å). The compounds Sr2Na0,5BWO6 crystallize with BIII ? Sm, Gd in a monoclinic and with BIII ? Y, In in a rhombic distorted perovskite lattice. For the perovskites with A = Sr — dependent on ionic radii of the B ions — two different lattice types are present. 相似文献
17.
On Perovskites Ba2B B TeVIO6 Compounds of composition Ba2BBTeVIO6 with BI = Li, Na; BIII = 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. 相似文献
18.
Crystal Structure and Properties of Calcium and Strontium Hexathiodiphosphate(IV), Ca2P2S6 and Sr2P2S6, with a Contribution on Ca5P8 and Pb2P2S6 Ca2P2S6 and Sr2P2S6 were prepared from metal and a mixture of red phosphorus and sulfur (molar ratio M:P:S = 1:1:3) in 2 corundum crucibles inserted in quartz ampullae under vacuum (20 d 900°C). The compounds were obtained as colourless, crystalline powders containing single crystals. They crystallize in the Sn2P2S6 (high temperature form) type structure (P21/c, Z = 2): Ca2P2S6 a = 653.2(2)pm, b = 728.1(2)pm, c = 1110.1(4)pm, β = 124.00(4)°, d = 2.50(2); Sr2P2S6 a = 664.3(2)pm, b = 755.7(3)pm, c = 1139.7(3)pm, β = 124.07(2)°, d = 2.97(2). The anions P2S have staggered confirmation and are arranged with the motif of a cubic close-packing. Sr2+ is coordinated by 8S which form a twofold face-capped trigonal prism and belong to 4P2S. Structure calculations clearly show that Pb2P2S6 also crystallizes in P21/c and not in Pc [1]. Also, Raman- and IR-spectra of Ca5P8 were recorded at 20°C. The stretching vibrations of P were assigned in analogy to those of P2S in alkaline earth hexathiodiphosphates(IV). The range of their frequencies (480 to 340 cm?1) is essentially smaller and shifted to smaller values compared with P2S in Ca2P2S6 and Sr2P2S6 (620 to 390 cm?1). The symmetry of P is not D3d but C2h as in the case of P2S. 相似文献
19.
Synthesis, Crystal Structure and Spectroscopic Properties of the Cluster Anions [(Mo6Br )X ]2? with Xa = F, Cl, Br, I The tetrabutylammonium (TBA), tetraphenylphosphonium (TPP) and tetraphenylarsonium (TPAs) salts of the octa-μ3-bromo-hexahalogeno-octahedro-hexamolybdate(2?) anions [(Mo6Br)X]2? (Xa = F, Cl, Br, I) are synthesized from solutions of the free acids H2[(Mo6Br)X] · 8 H2O with Xa = Cl, Br, I. The crystal structures show systematic stretchings in the Mo? Mo bond length and a slight compression of the Bri8 cube in the Fa to Ia series. The cations do not change much. The i.r. and Raman spectra show at 10 K almost constant frequencies of the (Mo6Bri8) cluster vibrations, whereas all modes with Xa ligand contribution are characteristically shifted. The most important bands are assigned by polarization measurements and the force constants are derived from normal coordinate analysis. The 95Mo nmr signals are shifted to lower field with increasing electronegativity of the Xa ligands. The fluorine compound shows a sharp 19F nmr singlet at ?184.5 ppm. 相似文献
20.
P. Khl 《无机化学与普通化学杂志》1973,401(2):121-131
The Crystal Structure of Perovskites A NiIIMVIO6. II. Sr2NiWO6 The results of an X-ray single crystal study of the perovskite Sr[NiIIWVI](6)O6, ordered in the octahedral sites, are given. While Sr[NiIITeVI](6)O6 crystallizes in a monoclinically deformed structure of the perovskite (elpasolite) type, showing a phase transition to a tetragonal lattice at 675 °K, Sr[NiIIWVI](6)O6 is tetragonal already at 298°K (space group: C; a = b = 5.559 Å; c = 7.918 Å; Z = 2). The Ni? O distances found for the tungsten compound are nearly identical with those of the tellurium perovskite. In contradiction to crystal field theory very different values of the ligand field parameter Δ (ca. 25%) are observed for these two compounds however. Obviously this effect is caused by the rather different kind of bonding within the NiO6 polyhedra in the two compounds. On the basis of the structural results the Ni? O-bonding in the two perovskites is discussed in dependence of the next nearest cationic environment. 相似文献