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1.
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   

2.
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   

3.
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   

4.
On the Crystal Structure of O MF (M = Sb, Ru, Pt, Au) OMF (M = Sb, Ru, Pt, Au) were obtained again, but for the first time investigated by X-ray methods. Colourless OSbF and the rubyred compounds ORuF and OPtF crystallize isostructural in space group Ia3 -Th7 (Nr. 206) with a = 1016(1) pm (Sb), a = 1002.6(9) pm (Ru) and a = 1003.6(9) pm (Pt), Z = 8. Yellow OAuF crystallizes trigonal-rhombohedric in space group R3 -D326 (Nr. 148) with a = 775.9(3) pm, c = 711.7(4) pm, Z = 3.  相似文献   

5.
On the Formation of Polysulphane Diphosphonates by the Reaction of Monothiophosphonate with Disulphane Diphosphonate In acid solution SPO reacts with S2P2O forming higher polysulphane diphosphonates. The formation of S3P2O and S4P2O is proved by evaluation of the double labelling with 35S? 32P after high paper electrophoresis.  相似文献   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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–1NCS).  相似文献   

11.
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   

12.
Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 53. Preparation, Properties, and Vibrational Spectra of the Cage Anions P113? and As113? The Zintl-phases M3X11 (M = Na, K, Rb, Cs; X = P, As) are prepared from the elements or from M3X7 and X. The compounds undergo a first-order phase transition from the crystalline to the plastically crystalline state. Unit cell and space group of both modifications and the transition temperature Tc are determined. The vibrational spectra of the crystalline compounds and the Raman spectrum of the P113? anion in en-solution as well are measured. The assignment of the frequencies is given, based on the 32-D3 symmetry of the X113? cage anion. Normal coordinate analysis is carried out in terms of Cartesian coordinates to avoid the problem of redundancies in using internal coordinates. The force constants [mdyn Å?1] obtained for the characteristic bonds r, s, and t are: f = 1.34, f = 1.20, f = 1.08; f = 1.1, f = 0.91. Normal vibrations and the potential energy distribution (PED) are discussed.  相似文献   

13.
On the Formation of Polysulphane Phosphonsulphonates by the Reaction of SPO with Polythionates and S2O with Disulphane Diphosphonate Polysulphane diphosphonates and polysulphane phosphonsulphonates are formed in the reaction of SPO and polysulphane disulphonates in acid solution. The polysulphane phosphonsulphonates are described here for the first time. The same products yielded when S2O reacts with S2P2O. The formation of these compounds depends on nucleophilic attack of the SPO on the sulfur chains of the starting materials, during which growth of the sulfur chains partly occurs.  相似文献   

14.
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.  相似文献   

15.
High Resolution Electron Microscopy Investigations of La2CeTaO6Cl3 and its Thermal Decomposition Product La2Ce Ce TaO6Cl3?x The thermal decomposition of the hexagonal La2CeTaO6Cl3 led to a mixed-valent product La2CeCe TaO6Cl3?x with a complicated monoclinic structure. The detailed inspection shows two subunits A and B, which form the monoclinic unit cell by a ABAB sequence. The subunit A is almost identical to the hexagonal cell of the starting material while subunit B has additional Ln- and Cl-positions. For this reason, the main structure features of the monoclinic compound and the starting material are related, which is clearly seen in the electron microscopy investigations. As might be expected from the relationship between the subunits A and B one can observe defects in the monoclinic compound arising from the various possibilities of combining these building elements. We also found structure defects in the hexagonal starting material, which are caused by the presence of the subunit B.  相似文献   

16.
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   

17.
The coordination polymers [(CuCN)2(μ-2 Mepyz)], [CuCN(μ-2 Mepyz)] and [CuCN(μ-4 Mepym)] ( 1 – 3 ) (2 Mepyz = 2-methylpyrazine; 4 Mepym = 4-methylpyrimidine) may be prepared by self-assembly in acetonitrile solution at 100 °C ( 1 , 3 ) or without solvent at 20 °C ( 2 ). All three contain [CuCN] chains that are bridged by the bidentate aromatic ligands into sheets in 1 and 3 D frameworks in 2 and 3 . Reaction of CuSCN with these heterocyclic diazines at 100 °C leads to formation of the lamellar coordination polymers [(CuSCN)(μ-2 Mepyz)] ( 4 ) and [CuSCN · (4 Mepym-κN1)] ( 5 ), which contain respectively [CuSCN] chains and trans-trans fused [CuSCN] sheets as substructures. The presence of an asymmetric substitution pattern in 2 Mepyz and 4 Mepym induces the adoption of a chiral structure by 2 and 5 (space groups P212121 and P1).  相似文献   

18.
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   

19.
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?, CO2Y2?, COY, NOY?, NO2Y?, PO3Y3?, PO2Y and SO2Y2? are described. (Y ? C(CN)2, NCN.) The preparation of some triorganoleadacyles is reported.  相似文献   

20.
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   

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