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1.
2.
Shielding by four TeCl 4 molecules is observed for the distorted rhombic dodecahedron core of the tellurium nitride Te6N8 (see picture). With the characterization of this structure, the composition of the tellurium nitride discovered 100 years ago has now been determined. As a result of the shielding effect, the explosive character of the nitride is lost.  相似文献   

3.
A three‐step one‐pot synthetic procedure to synthesize the neutral tellurium(IV) coordination compounds PhTeX3L (X = Br, I and L = ethylenethiourea) has been developed and is described in this article. Oxidative halogenation of PhTeTePh in methanol generates the tellurium(II) derivative, PhTeX, which is subsequently complexed with ethylenethiourea, and, finally, further oxidative addition of additional halogen affords the corresponding tellurium(IV) compound PhTeX3L in good yields. The final product was obtained by the slow evaporation of the reaction mixture as black crystals. The X‐ray structural analyses of the compounds show Te···X and X···X secondary interactions in the solid state and suggest a weak dependence of the formation of supramolecular assemblies on the nature of the halogen bonded to the tellurium atom.  相似文献   

4.
The Novel cis‐[Bi3I12]3?‐Anion in Tri(n‐butyl)methylammoniumdodecaiodo‐tribismutate By reaction of equivalent amounts of BiI3, KI and I2 in [N(CH3) (n‐C4H9)3][N(SO2CF3)2] as Ionic Liquid, transparent reddish crystals with the composition [N(CH3)(n‐C4H9)3]3[Bi3I12] are formed. Concerning to X‐ray diffraction investigations based on single crystals as well as powders, [N(CH3)(n‐C4H9)3]3[Bi3I12] crystallizes monoclinic (P21/c; a = 2383.0(5); b = 1241.0(3); c = 2493.0(5) pm; β = 97.50(3)°; Z = 4). The anion consists of distorted (BiI6)‐octahedra, which are face‐shared via cis‐oriented octahedral faces. With the cis‐[Bi3I12]3?‐anion such a connectivity is firstly described.  相似文献   

5.
The tellurium(II) dithiolates Te[SCH2CH2C(O)OCH3]2, ( 1 ), Te[SCH2CH2CH2SC(O)CH3]2, ( 2 ), and Te[SCH2CH2CH2CH2SC(O)CH3]2, ( 3 ) were synthesized from Te(StBu)2 and the corresponding thiol. All compounds are sensitive toward higher temperatures and light and decompose to elemental tellurium and the disulfide. In the solid state, the Te atom of 1 exhibits the novel Te(S2Te2) coordination mode. Additionally to the two Te—S bonds, each Te atom forms two long Te···Te contacts to neighboring molecules, leading to a coordination number of four and a distorted sawhorse configuration. No intramolecular Te···O interactions are present in the solid state, in accordance with ab initio calculations (MP2/ecp‐basis) for the isolated molecule. 125Te NMR shifts of all compounds lay within a narrow range and close to the respective shift of other Te(SCH2R)2 compounds. VT 125Te NMR spectra gave no hint to donor acceptor interactions in solution for any of the compounds and thus corroborate results from IR‐spectroscopy, ab initio geometry optimizations, and thermochemical calculations.  相似文献   

6.
The first Te–Mn–CO clusters were obtained by the thermal reaction of K2TeO3 with [Mn2(CO)10] in MeOH. The basicity of the μ4-Te ligand in the octahedral cluster anion [(μ4-Te)2Mn4(CO)12]2− is demonstrated by its binding to the fragment [(TeMe2)Mn(CO)4]+ in an axial fashion to afford the novel cluster 1 .  相似文献   

7.
The novel mercury‐tellurium cluster [Hg8(μ‐n‐C3H7Te)122‐Br)Br3] is formed during the reaction of HgBr2 and (n‐C3H7Te)2Hg in DMSO. Its crystal structure has been elucidated showing [Hg8(μ‐n‐C3H7Te)122‐Br)]3+ units with a bromine‐centered distorted Hg8 cube. The mercury atoms are bridged by n‐C3H7Te ligands and the resulting clusters are linked to a three‐dimensional network by bromine atoms. The close packing of the cluster is mainly determined by the flexible n‐propyl residues of the telluride building blocks.  相似文献   

8.
A solution of sodium in liquid ammonia reacts with Sb2S3 to form large colorless crystals of the composition Na3SbS3⋅10 NH3. The trigonal‐pyramidal SbS33− anion is ion‐paired with three Na+ counter ions, the coordination spheres of which are completed by eight ammine ligands. The resulting neutral [Na(NH3)3]2[Na(NH3)2]SbS3 molecules crystallize together with two ammonia molecules of solvation in the space group P21/c (a=9.828(2), b=6.0702(4), c=33.4377(6) Å, β=91.362(7)°, V=1994.2(5) Å3, Z=4).  相似文献   

9.
SmCl3 reacts with Me3SiCH2Li in THF yielding Sm(CH2SiMe3)3(THF)3 ( 1 ). The single crystal X‐ray structural analyses of 1 , Er(CH2SiMe3)3(THF)2 ( 2 ), Yb(CH2SiMe3)3(THF)2 ( 3 ), and Lu(CH2SiMe3)3(THF)2 ( 4 ) show the Sm atom in a fac‐octahedral coordination and the heavier lanthanides Er, Yb, and Lu trigonal bipyramidally coordinated with the three alkyl ligands in equatorial and two THF molecules in axial positions.  相似文献   

10.
The reaction of Mes2TeF2 (Mes = 2,4,6‐trimethylphenyl) with trimethylsilyl cyanide yields the corresponding tellurium(IV) dicyanide Mes2Te(CN)2. Isolation of suitable crystals allows the determination of the first crystal structure of a compound of the type R2Te(CN)2.  相似文献   

11.
The new [SnBi3]5− polyanion is obtained by the reaction of K3Bi2 with K4Sn9 or K12Sn17 in liquid ammonia. The anion is iso(valence)electronic with and structurally analogous to the carbonate ion. Despite the high negative charge of the anion, the Sn−Bi bond lengths range between single and double bonds. Quantum‐chemical calculations at a DFT‐PBE0/def2‐TZVPP/COSMO level of theory reveal that the partial double bond character between the heavy main‐group atoms Bi and Sn originates from a delocalized π‐electronic system. The structure of the anion is determined by single‐crystal X‐ray diffraction analyses of the compounds K5[SnBi3] 9 NH3 ( 1 ) and K9[K(18‐crown‐6)][SnBi3]2⋅15 NH3 ( 2 ). The [SnBi3]5− unit is the first example of a carbonate‐like anion obtained from solution, and it consists exclusively of metal atoms and completes the series of metal analogues of CO and CO2.  相似文献   

12.
Preparation and Structure of (3‐Methylpyridinium)3[DyCl6] and (3‐Methylpyridinium)2[DyCl5(Ethanol)] The complex chlorides (3‐Methylpyridinium)3[DyCl6] ( 1 ) and (3‐Methylpyridinium)2[DyCl5(Ethanol)] ( 2 ) have been prepared for the first time. The crystal structures have been determined from single crystal X‐ray diffraction data. 1 crystallizes in the trigonal space group R3c (Z = 36) with a = 2953.3(3) pm, b = 2953.3(3) pm and c = 3252.5(4) pm, compound 2 crystallizes in the triclinic space group P1 (Z = 2) with a = 704.03(8) pm, b = 808.10(8) pm, c = 1937.0(2) pm, α = 77.94(1)°, β = 87.54(1)° and γ = 83.26(1)°. The structures contain isolated octahedral building units [DyCl6]3– and [DyCl5(Ethanol)]2–, respectively.  相似文献   

13.
The reaction of Cp2Sm(THF) with 1,2-dibromoethane or 1,2-diiodoethane leads to an equimolar mixture of Cp3Sm(THF) and CpSmX2(THF)3 (X = Br, I). CpSmBr2(THF)3 crystallizes in the monoclinic system (P21, Z = 2, a = 804.6(1), b = 1507.6(2), c = 913.8(1) pm, β = 107.36(1)°, R1 = 0.0327, wR2 = 0.0578), while CpSmI2(THF)3 is orthorhombic (Pna21, Z = 4, a = 1950.6(3), b = 1377.1(2), c = 831.93(9) pm, R1 = 0.0438, wR2 = 0.0412). The ligand arrangement around the formally eight coordinate Sm atom is a distorted octahedron with the centroid of the Cp-ring and one THF-molecule in the apical positions, whilst the halides are transoid in the equatorial plane.  相似文献   

14.
By reaction of GeI4, [N(nBu)4]I as iodide donor, and [NMe(nBu)3][N(Tf)2] as ionic liquid, reddish‐black, plate‐like shaped crystals are obtained. X‐ray diffraction analysis of single crystals resulted in the compositions ;alpha;‐[NMe(nBu)3](GeI4)I (Pbca; a = 1495.4(3) pm; b = 1940.6(4) pm; c = 3643.2(7) pm; Z = 16) and β‐[NMe(nBu)3](GeI4)I (Pn; a = 1141.5(2) pm; b = 953.6(2) pm; c = 1208.9(2) pm; β = 100.8(1)°; Z = 2). Depending on the reaction temperature, the one or other compound is formed selectively. In addition, the reaction of GeI4 and [N(nBu)4]I, using [ImMe(nBu)][BF4] (Im = imidazole) as ionic liquid, resulted in the crystallization of [ImMe(nBu)][N(nBu)4](GeI4)3I2 (P21/c; a = 1641.2(3) pm; b = 1903.0(4) pm; c = 1867.7(4) pm; β = 92.0(1)°; Z = 4). The anionic network of all three compounds is established by molecular germanium(IV)iodide, which is bridged by iodide anions. The different connectivity of (GeI4–I) networks is attributed to the flexibility of I regarding its coordination and bond length. Here, a [3+1]‐, 4‐ and 5‐fold coordination is first observed in the pseudo‐ternary system M/Ge/I (M: cation).  相似文献   

15.
Quaternary Cesium Copper(I) Lanthanoid(III) Selenides of the Type CsCu3M2Se5 (M = Sm, Gd — Lu) By oxidation of mixtures of copper and lanthanoid metal with elemental selenium in molar ratios of 1 : 1 : 2 and in addition of CsCl quaternary cesium copper(I) lanthanoid(III) selenides with the formula CsCu3M2Se5 (M = Sm, Gd — Lu) were obtained at 750 °C within a week from torch‐sealed evacuated silica tubes. An excess of CsCl as flux helps to crystallize golden yellow or red, needle‐shaped, water‐resistant single crystals. The crystal structure of CsCu3M2Se5 (M = Sm, Gd — Lu) (orthorhombic, Cmcm, Z = 4; e. g. CsCu3Sm2Se5: a = 417.84(3), b = 1470.91(8), c = 1764.78(9) pm and CsCu3Lu2Se5: a = 407.63(3), b = 1464.86(8), c = 1707.21(9) pm, respectively) contains [MSe6]9— octahedra which share edges to form double chains running along [100]. Those are further connected by vertices to generate a two‐dimensional layer parallel to (010). By edge‐ and vertex‐linking of [CuSe4]7— tetrahedra two crystallographically different Cu+ cations build up two‐dimensional puckered layers parallel to (010) as well. These sheet‐like structure interconnects the equation/tex2gif-stack-3.gif{[M2Se5]4—} layers to create a three‐dimensional network according to equation/tex2gif-stack-4.gif{[Cu3M2Se5]}. Thus empty channels along [100] form, apt to take up the Cs+ cations. These are surrounded by eight plus one Se2— anions in the shape of (2+1)‐fold capped trigonal prisms with Cs—Se distances between 348 and 368 pm (8×) and 437 (for M = Sm) or 440 pm (for M = Lu), respectively, for the ninth ligand.  相似文献   

16.
LiOH is one of the strong bases among neutral molecules. What about hydroxides of small Lin (n = 2 ? 5) clusters? The addition of a single atom to a cluster sometimes has dramatic effects on its reactivity. This fact motivated us to perform an ab initio MP2/6‐311++G(d, p) investigation on LinOH species (n = 1 ? 5). These LinOH species are stabilized by both ionic as well as covalent interactions, and are found to be stable against elimination of LiOH and OH. We have determined their gas and aqueous phase basicity by considering hypothetical protonation reactions. The calculated proton affinities of LinOH (n ≥ 2) suggest their reduced basicity as compared to LiOH by 50–100 kJ/mol. The NBO charges and the highest occupied molecular orbitals also reveal the electride and alkalide characteristics of Li2OH and Li3OH, respectively. © 2016 Wiley Periodicals, Inc.  相似文献   

17.
The tellurenyl fluoride, 2‐Me2NCH2C6H4TeF, was obtained from reaction of the tellurenyl iodide RTeI with AgF. The compound was unambiguously identified by 19F and 125Te NMR spectroscopy. The decomposition under disproportionation leads to the tellurium(IV) trifluoride, 2‐Me2NCH2C6H4TeF3 and the ditelluride RTeTeR. The fluorination of the ditelluride, (2‐Me2NCH2C6H4Te)2, with XeF2 results in pure RTeF3. The molecular structure of 2‐Me2NCH2C6H4TeF3, the second structural characterized tellurium(IV) trifluoride, has been determined. Furthermore the syntheses of the new tellurium(IV) difluoride, (2‐Me2NCH2C6H4)2TeF2, and corresponding tellurium(IV) diazide, (2‐Me2NCH2C6H4)2Te(N3)2 as well as the tellurium(IV) triazide, 2‐Me2NCH2C6H4Te(N3)3, and their characterization by spectroscopic methods were reported. During these investigations a rather interesting tellurium(VI) species was formed and the molecular structure of a subsequent product, [(2‐Me2NHCH2C6H4)2TeF3O]2(SiF6), was elucidated. Theoretical investigations for the compounds containing the stabilizing 2‐dimethylaminomethylphenyl substituent are illustrated.  相似文献   

18.
Spectroscopic Characterization and Crystal Structure of Trifluoromethyl Iodine(III) Chloride Trifluororacetate (CF3I(Cl)OCOCF3) The ternary iodine(III) compound CF3I(Cl)OCOCF3 is obtained by reaction between CF3I(Cl)F and (CH3)3SiOCOCF3 at –50 °C. The molecule was characterized by vibrational spectra, NMR‐spectra, and a crystal structure analysis. CF3I(Cl)OCOCF3 crystallizes monoclinic in the space group P21/c with a = 1102.7(1) pm, b = 785.6(1) pm, c = 989.7(1) pm, and β = 101.34(1)°.  相似文献   

19.
20.
The global minimum structures of AlB3H2n (n = 0–6) clusters are determined using the stochastic search method at the B3LYP/6–31G level of theory. These initially specified geometries are recalculated using B3LYP and CCSD(T) methods using the 6–311++G** basis set. The structural and electronic properties of the two lowest‐lying isomers are presented. The structural parameters obtained for aluminum borohydride are compared with the experimental and theoretical results. The H2 fragmentation energies of the most stable isomers are investigated. Chemical bonding analyses for the global minimum of AlB3H2n (n = 0–6) clusters are performed using the adaptive natural density partitioning method. © 2014 Wiley Periodicals, Inc.  相似文献   

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