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1.
Oxide methanesulfonates of Mo, U, Re, and V have been prepared by reaction of MoO(3), UO(2)(CH(3)COO)(2)·2H(2)O, Re(2)O(7)(H(2)O)(2), and V(2)O(5) with CH(3)SO(3)H or mixtures thereof with its anhydride. These compounds are the first examples of solvent-free oxide methanesulfonates of these elements. MoO(2)(CH(3)SO(3))(2) (Pbca, a=1487.05(4), b=752.55(2), c=1549.61(5) pm, V=1.73414(9) nm(3), Z=8) contains [MoO(2)] moieties connected by [CH(3)SO(3)] ions to form layers parallel to (100). UO(2)(CH(3)SO(3))(2) (P2(1)/c, a=1320.4(1), b=1014.41(6), c=1533.7(1) pm, β=112.80(1)°, V=1.8937(3) nm(3), Z=8) consists of linear UO(2)(2+) ions coordinated by five [CH(3)SO(3)] ions, forming a layer structure. VO(CH(3)SO(3))(2) (P2(1)/c, a=1136.5(1), b=869.87(7), c=915.5(1) pm, β=113.66(1)°, V=0.8290(2) nm(3), Z=4) contains [VO] units connected by methanesulfonate anions to form corrugated layers parallel to (100). In ReO(3)(CH(3)SO(3)) (P1, a=574.0(1), b=1279.6(3), c=1641.9(3) pm, α=102.08(2), β=96.11(2), γ=99.04(2)°, V=1.1523(4) nm(3), Z=8) a chain structure exhibiting infinite O-[ReO(2)]-O-[ReO(2)]-O chains is formed. Each [ReO(2)]-O-[ReO(2)] unit is coordinated by two bidentate [CH(3)SO(3)] ions. V(2)O(3)(CH(3)SO(3))(4) (I2/a, a=1645.2(3), b=583.1(1), c=1670.2(3) pm, β=102.58(3), V=1.5637(5) pm(3), Z=4) adopts a chain structure, too, but contains discrete [VO]-O-[VO] moieties, each coordinated by two bidentate [CH(3)SO(3)] ligands. Additional methanesulfonate ions connect the [V(2)O(3)] groups along [001]. Thermal decomposition of the compounds was monitored under N(2) and O(2) atmosphere by thermogravimetric/differential thermal analysis and XRD measurements. Under N(2) the decomposition proceeds with reduction of the metal leading to the oxides MoO(2), U(3)O(7), V(4)O(7), and VO(2); for MoO(2)(CH(3)SO(3))(2), a small amount of MoS(2) is formed. If the thermal decomposition is carried out in a atmosphere of O(2) the oxides MoO(3) and V(2)O(5) are formed.  相似文献   

2.
Direct variable reaction coordinate transition state theory (VRC-TST) rate coefficients are reported for the (3)CH(2) + OH, (3)CH(2) + (3)CH(2), and (3)CH(2) + CH(3) barrierless association reactions. The predicted rate coefficient for the (3)CH(2) + OH reaction (approximately 1.2 x 10(-10) cm(3) molecule(-1) s(-1) for 300-2500 K) is 4-5 times larger than previous estimates, indicating that this reaction may be an important sink for OH in many combustion systems. The predicted rate coefficients for the (3)CH(2) + CH(3) and (3)CH(2) + (3)CH(2) reactions are found to be in good agreement with the range of available experimental measurements. Product branching in the self-reaction of methylene is discussed, and the C(2)H(2) + 2H and C(2)H(2) + H2 products are predicted in a ratio of 4:1. The effect of the present set of rate coefficients on modeling the secondary kinetics of methanol decomposition is briefly considered. Finally, the present set of rate coefficients, along with previous VRC-TST determinations of the rate coefficients for the self-reactions of CH(3) and OH and for the CH(3) + OH reaction, are used to test the geometric mean rule for the CH(3), (3)CH(2), and OH fragments. The geometric mean rule is found to predict the cross-combination rate coefficients for the (3)CH(2) + OH and (3)CH(2) + CH(3) reactions to better than 20%, with a larger (up to 50%) error for the CH(3) + OH reaction.  相似文献   

3.
根据稀土离子能级的特点,对Ga2O3-La2O3-Yb2O3-Er2O3(HO2O3)体系的光谱性质进行了探讨,发现它们有二类发光性质:Stokes发光和反Stokes发光,研究了发光强度和发射波长与掺杂离子的依赖关系,观察到由能量的共振转移引起的荧光浓度猝灭现象,并取得了最大发光强度时的掺杂离子浓度和一些规律性结果.  相似文献   

4.
FT IR and FT Raman spectra of Ag3(PO2NH), (Compound 1), Na3(PO2NH)3 x H2O (Compound II), Na3(PO2NH)3 x 4H2O (Compound III), [C(NH2)3]3(PO2NH)3 x H2O (Compound IV) and (NH4)4(PO2NH)4 x 4H2O (Compound V) are recorded and analyzed on the basis of the anions, cations and water molecules present in each of them. The PO2NH- anion ring in compound I is distorted due to the influence of Ag+ cation. Wide variation in the hydrogen bond lengths in compound III is indicated by the splitting of the v2 and v3 modes of vibration of water molecules. The NH4 ion in compound V occupies lower site symmetry and exhibits hindered rotation in the lattice. The correlations between the symmetric and asymmetric stretching vibrations of P-N-P bridge and the P-N-P bond angle have also been discussed.  相似文献   

5.
Bauer S  Müller H  Bein T  Stock N 《Inorganic chemistry》2005,44(25):9464-9470
Following the strategy of using polyfunctional phosphonic acids for the synthesis of open-framework metal phosphonates, the phosphonocarboxylic acid (H2O3PCH2)2NCH2C6H4COOH was used in the hydrothermal synthesis of new Ba phosphonates. Its decomposition led to the first open-framework barium phosphonate [Ba3(O3PCH2NH2CH2PO3)2(H2O)4].3H2O. The synthesis was also successfully performed using iminobis(methylphosphonic acid), (H2O3PCH2)2NH, as a starting material, and the synthesis was optimized to obtain as a pure material. The reaction setup as well as the pH are the dominant parameters, and only a diffusion-controlled reaction led to the desired compound. The crystal structure was solved from single-crystal data: monoclinic; C2/c; a=2328.7(2), b=1359.95(7), and c=718.62(6) pm; beta=98.732(10) degrees ; V=2249.5(3)x10(6) pm3; Z=4; R1=0.036; and wR2=0.072 (all data). The structure of [Ba3(O3PCH2NH2CH2PO3)2(H2O)4].3H2O is built up from BaO8 and BaO10 polyhedra forming BaO chains and layers, respectively. These are connected to a three-dimensional metal-oxygen-metal framework with the iminobis(methylphosphonic acid) formally coating the inner walls of the pores. The one-dimensional pores (3.6x4 A) are filled with H2O molecules that can be thermally removed. Thermogravimetric investigations and temperature-dependent X-ray powder diffraction demonstrate the stability of the crystal structure up to 240 degrees C. The uptake of N,N-dimethylformamide and H2O by dehydrated samples is demonstrated. Furthermore, IR, Raman, and 31P magic-angle-spinning NMR data are also presented.  相似文献   

6.
Crystals of PbCu3(OH)(NO3)(SeO3)3·1/2H2O [a=7.761(3)Å,b=9.478(4)Å,c=9.514(4)Å, =66.94(2)°, =69.83(2)°, =81.83(2)°, space group P ,Z=2] and Pb2Cu3O2(NO3)2(SeO3)2 [a=5.884(2)Å,b=12.186(3)Å,c=19.371(4)Å, space group Cmc21,Z=4] were synthesized under hydrothermal conditions. Their crystal structures were refined with three-dimensional X-ray data toR w=0.033 resp. 0.055. In PbCu3(OH)(NO3)(SeO3)3·1/2H2O the Cu atoms are [4+1] and [4+2] coordinated and via SeO3 groups a three-dimensional atomic arrangement is built up. In Pb2Cu3O2(NO3)2(SeO3)2 there are sheets, which are connected only via Pb-O bonds ranging from 2.98 Å to 3.16 Å.
  相似文献   

7.
The title compounds have been respectively synthesized by solution process and solvothermal reaction, and their crystal structures were determined by X-ray diffraction method. For (CH3CH2CH2CH2NH3)6(BiI6)(I)2I3 1, it crystallizes in tficlinic, space group P1^- with Mr = 2049.76, a = 8.5719(1), b = 11.7461(3), c = 15.700(1)A, V = 1451.4(1)A^3, Z = 1, Dc = 2.345 g/cm^3, F(000) = 924, μ(MoKα) = 8.907 mm^-1, T = 293(2) K, the final R = 0.0655 and wR = 0.0804 for 2399 observed reflections with I 〉 2σ(I). For (NH3CH2CH2NH3)2Bi2I10 2, it crystallizes in monoclinic, space group P21/n with Mr= 1811.20, a = 8.434(4), b = 13.862(6), c = 13.362(6)A, V = 1499.9(12)A^3, Z = 2, Dc = 4.010 g/cm^3, F(000) = 1536,μ(MoKα) = 22.007 mm^-1, T = 293(2) K, the final R = 0.0584 and wR = 0.1451 for 1798 observed reflections with I 〉 2σ(I). The structures of 1 and 2 contain halobismuthate monomer and dimers, respectively. It is noteworthy that the dimers and their organic counters in 2 connect each other by N…I hydrogen bonds to form a layered structure, and the electrostatic interactions and crystal packing forces between layers give rise to the packing of the crystal. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.13 and 2.01 eV, respectively.  相似文献   

8.
MoO3/TiO2-Al2O3催化剂表面结构的LRS研究   总被引:7,自引:0,他引:7  
负载型Mo和Co-Mo催化剂由于工业上的广泛应用,多年来一直是催化工作者的重要研究课题.工业上应用的Mo和Co-Mo催化剂多以活性Al_2O_3和SiO_2-Al_2O_3为载体,近年来也有用TiO_2,ZrO_2和活性碳作为催化剂载体的研究报导.有关催化剂活性组分与载体之间相互作用对催化剂表面相结构和催化性能的影响方面研究已引起人们的重视。我们多年来在金属-载体相互作用研究基础上,以石油加氢精制催化剂为应用背景,开  相似文献   

9.
2MgO·2B_2O_3·MgCl_2·14H_2O-H_3BO_3-H_2O体系30℃相平衡   总被引:5,自引:0,他引:5  
用相平衡方法研究了2MgO·2B_2O_3·MgCl_2·14H_2O-H_3BO_3-H_2O在30 ℃ 不同浓度H_3BO_3水溶液中的溶解转化产物及其溶解度。结果表明,氯柱硼镁石的 溶解转化产物,在H_3BO_3质量分数≤2.50%时为多水硼镁石;在2.50% ~ 5. 00%H_3BO_3范围时为库水硼镁石;当H_3BO_3量在5.00% ~ 5.60%之间时为章氏硼 镁石;而当H_3BO_3量≥5.60%时为三方硼镁石。提出了溶解相转化机理。  相似文献   

10.
The intermolecular interaction energy curves of CH(3)OCH(3)-CH(2)F(2), CF(3)OCH(3)-CH(2)F(2), CF(3)OCF(3)-CH(2)F(2), CH(3)OCH(3)-CHF(3), CF(3)OCH(3)-CHF(3), and CF(3)OCF(3)-CHF(3) complexes were calculated by the MP2 level ab initio molecular orbital method using the 6-311G** basis set augmented with diffuse polarization functions. We investigate the fluorine substitution effects of both methane and dimethyl ether on intermolecular interactions. In addition, orientation dependence of intermolecular interaction energies is also studied with utilizing eight types of orientations. Our analyses demonstrate that partial fluorinations of methane make electrostatic interaction dominant, and consequently enhance attractive interaction at several specific orientations. On the contrary, fluorine substitutions of dimethyl ether substantially decrease the electrostatic interaction between ether and CH(2)F(2) or CHF(3); thus, there is no such characteristic interaction between the C-H of fluorinated methane and ether oxygen of CF(3)OCF(3) as conventional hydrogen bonding, due to reduced polarity of fluorinated ether. The combination of different pairs of the electrostatic interaction is therefore responsible for the intermolecular interaction differences among the complexes investigated herein and also their orientations.  相似文献   

11.
Two new silver-antimony sulfides, [C(2)H(9)N(2)][Ag(2)SbS(3)] (1) and [C(2)H(9)N(2)](2)[Ag(5)Sb(3)S(8)] (2), have been prepared solvothermally in the presence of ethylenediamine and characterized by single-crystal X-ray diffraction, thermogravimetry, and elemental analysis. Compound 1 crystallizes in the space group Pn (a = 6.1781(1) A, b =11.9491(3) A, c = 6.9239(2) A, beta =111.164(1) degrees ) and 2 in the space group Pm (a = 6.2215(2) A, b = 15.7707(7) A, c = 11.6478(5) A, beta = 92.645(2) degrees ). The structure of 1 consists of chains of fused five-membered Ag(2)SbS(2) rings linked to form layers, between which the template molecules reside. Compound 2 contains honeycomb-like sheets of fused silver-antimony-sulfide six-membered rings linked to form double layers. The idealized structure can be considered to be an ordered defect derivative of that of lithium bismuthide, Li(3)Bi, and represents a new solid-state structure type.  相似文献   

12.
Mechanochemical reaction of cluster coordination polymers 1infinity[M3Q7Br4] (M = Mo, W; Q = S, Se) with solid K2C2O4 leads to cluster core excision with the formation of anionic complexes [M3Q7(C2O4)3]2-. Extraction of the reaction mixture with water followed by crystallization gives crystalline K2[M3Q7(C2O4)3].0.5KBr.nH2O (M = Mo, Q = S, n = 3 (1); M = Mo, Q = Se, n = 4 (2); M = W, Q = S, n = 5 (3)). Cs2[Mo3S7(C2O4)3].0.5CsCl.3.5H2O (4) and (Et4N)1.5H0.5K{[Mo3S7(C2O4)3]Br}.2H2O (5) were also prepared. Close Q...Br contacts result in the formation of ionic triples {[M3Q7(C2O4)3](2)Br}5- in 1-4 and the 1:1 adduct {[Mo3S7(C2O4)3]Br}3- in 5. Treatment of 1 or 2 with PPh(3) leads to chalcogen abstraction with the formation of [Mo3(mu3-Q)(mu2-Q)3(C2O4)3(H2O)3]2-, isolated as (Ph4P)2[Mo3(mu3-S)(mu2-S)3(C2O4)3(H2O)3].11H2O (6) and (Ph4P2[Mo3(mu3-Se)(mu2-Se)3(C2O4)3(H2O)3].8.5H2O.0.5C2H5OH (7). All compounds were characterized by X-ray structure analysis. IR, Raman, electronic, and 77Se NMR spectra are also reported. Thermal decomposition of 1-3 was studied by thermogravimetry.  相似文献   

13.
The neutral pentacoordinate monoamidinatosilicon(IV) complex 1 (SiN(2)Cl(3) skeleton) and the neutral hexacoordinate monoamidinatosilicon(IV) complexes 2-9 (SiN(3)OF(2), SiN(3)OCl(2), SiN(3)OBr(2), SiN(5)O and SiN(3)O(3) skeletons) were synthesised and characterised by elemental analyses, single-crystal X-ray diffraction (except for 1) and NMR spectroscopy in the solid state and in solution. Compounds 2-9 contain one bidentate monoanionic N,N'-diisopropylbenzamidinato ligand, one bidentate monoanionic ligand derived from 8-hydroxyquinoline and (i) two identical monoanionic ligands (F, Cl, Br, N(3), NCO, NCS, OSO(2)CF(3)) or (ii) one bidentate dianionic benzene-1,2-diolato ligand. The dynamic behavior of 2-4 (SiN(3)OX(2) skeleton; X = F, Cl, Br) and 9 (SiN(3)O(3)) in solution was studied by multinuclear variable-temperature NMR experiments. Compound 1 was synthesised by reaction of SiCl(4) with the corresponding lithium amidinate, and compound 2 was obtained by reaction of 1 with 8-hydroxyquinoline and triethylamine. Compound 2 served as the starting material in the syntheses of 3-9, in which the two chloro ligands of 2 were substituted by two identical (pseudo)halogeno ligands, two trifluoromethanesulfonato ligands or one benzene-1,2-diolato ligand. Compounds 3 and 4 contain the novel SiN(3)OBr(2) and SiN(3)OF(2) skeletons, while compounds 5-7 are the first neutral hexacoordinate silicon(IV) complexes with an SiN(5)O skeleton.  相似文献   

14.
Vibrationally excited CF(2)ClCHFC(2)H(5)(CF(2)ClCHFC(2)D(5)) molecules were prepared in the gas phase at 300 K with approximately 93 kcal mol(-1) of energy by recombination of CF(2)ClCHF and C(2)H(5) or C(2)D(5) radicals. Three unimolecular reactions were observed. 1,2-ClF interchange converts CF(2)ClCHFC(2)H(5)(CF(2)ClCHFC(2)D(5)) into CF(3)CHClC(2)H(5)(CF(3)CHClC(2)D(5)), and subsequent 2,3-ClH (ClD) elimination gives CF(3)CH=CHCH(3) (CF(3)CH=CDCD(3)). 2,3-FH(FD) elimination gives cis- and trans-CF(2)ClCH=CHCH(3) (CF(2)ClCH=CDCD(3)), and 1,2-ClH elimination gives CF(2)=CFCH(2)CH(3) (CF(2)=CFCD(2)CD(3)). The experimental rate constants for CF(2)ClCHFC(2)H(5) (CF(2)ClCHFC(2)D(5)) were 1.3 x 10(4) (0.63 x 10(4)) s(-1) for 1,2-FCl interchange and 2.1 x 10(4) (0.61 x 10(4)) s(-1) with a trans/cis ratio of 3.7 for 2,3-FH(FD) elimination. The 1,2-ClH process was the least important with a branching fraction of only 0.08 +/- 0.04. The rate constants for 2,3-ClH (ClD) elimination from CF(3)CHClC(2)H(5) (CF(3)CHClC(2)D(5)) were 1.8 x 10(6) (0.49 x 10(6)) s(-1) with a trans/cis ratio of 2.4. Density functional theory was used to compute vibrational frequencies and structures needed to obtain rate constants from RRKM theory. Matching theoretical and experimental rate constants provides estimates of the threshold energies, E0, for the three reaction pathways; 1,2-FCl interchange has the lowest E0. The unimolecular reactions of CF(2)ClCHFC(2)H(5) are compared to those of CF(2)ClCHFCH(3). Both of these systems are compared to CH(3)CHFC(2)H(5) to illustrate the influence of a CF(2)Cl group on the E0 for FH elimination.  相似文献   

15.
Crystal Structure of Cs2PrO3 and also about Cs2CeO3, Cs2TbO3, Rb2CeO3, and Rb2TbO3 New prepared Cs2PrO3 (dark brown) is orthorhombic due to single crystal data, K2PbO3 type of structure (Cmc21) with a = 11.47, b = 7.722, c = 6.427 Å and Z = (4). Cs2CeO3 (colourless, a = 11.495, b = 7.753, c = 6.437 Å), Cs2TbO3 (red-brown, a = 11.37, b = 7.726, c = 6.142 Å), and the low-temperature form of (LT-) Rb2TbO3 (red-brown, a = 10.91, b = 7.390, c = 6.099 Å) are isotypic. Hitherto unknown HT-Rb2CeO3 (high-temperature form, colourless, a = 3.837, c = 18.47 Å, Z = 2, hexagonal) and “HT-Rb2TbO3” (red-brown, a = 3.773, c = 18.00 Å) correspond according to powder-data to the α-NaFeO2 type of structure. Cs2PrO3 has been measured magnetically (100–300 K). The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.  相似文献   

16.
Three gas-phase diatomic trications Se(2) (3+), Te(2) (3+), and LaF(3+) have been produced by Ar(+) ion beam sputtering of Se, Te, and LaF(3) surfaces, respectively. These exotic molecular ions were detected at noninteger m/z values in a magnetic sector mass spectrometer for ion flight times of >/=13 micros that correspond to lower limits of their respective lifetimes. Se(2) (3+) and Te(2) (3+) were unambiguously identified by their characteristic isotopic abundances. Ab initio calculations of the electronic structures of Se(2) (3+), Te(2) (3+), and LaF(3+) show that these molecular trications are metastable with respect to dissociation into fragment ions of Se(2+)+Se(+), Te(2+)+Te(+), and La(2+)+F(+), respectively. Their barrier heights are about 0.49, 0.29, and 0.53 eV, and the equilibrium internuclear distances (bond lengths) are about 0.23, 0.27, and 0.26 nm, respectively. The gas-phase diatomic dications Se(2) (2+) and Te(2) (2+) were also observed and unambiguously identified. They were found to be long-lived metastable molecules as well, whereas LaF(2+) is thermochemically stable.  相似文献   

17.
Five new vanadium selenites, Ca(2)(VO(2))(2)(SeO(3))(3)(H(2)O)(2), Sr(2)(VO(2))(2)(SeO(3))(3), Ba(V(2)O(5))(SeO(3)), Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), and Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), have been synthesized and characterized. Their crystal structures were determined by single crystal X-ray diffraction. The compounds exhibit one- or two-dimensional structures consisting of corner- and edge-shared VO(4), VO(5), VO(6), and SeO(3) polyhedra. Of the reported materials, A(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)) (A = Sr(2+) or Pb(2+)) are noncentrosymmetric (NCS) and polar. Powder second-harmonic generation (SHG) measurements revealed SHG efficiencies of approximately 130 and 150 × α-SiO(2) for Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)) and Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), respectively. Piezoelectric charge constants of 43 and 53 pm/V, and pyroelectric coefficients of -27 and -42 μC/m(2)·K at 70 °C were obtained for Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)) and Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), respectively. Frequency dependent polarization measurements confirmed that the materials are not ferroelectric, that is, the observed polarization cannot be reversed. In addition, the lone-pair on the Se(4+) cation may be considered as stereo-active consistent with calculations. For all of the reported materials, infrared, UV-vis, thermogravimetric, and differential thermal analysis measurements were performed. Crystal data: Ca(2)(VO(2))(2)(SeO(3))(3)(H(2)O)(2), orthorhombic, space group Pnma (No. 62), a = 7.827(4) ?, b = 16.764(5) ?, c = 9.679(5) ?, V = 1270.1(9) ?(3), and Z = 4; Sr(2)(VO(2))(2)(SeO(3))(3), monoclinic, space group P2(1)/c (No. 12), a = 14.739(13) ?, b = 9.788(8) ?, c = 8.440(7) ?, β = 96.881(11)°, V = 1208.8(18) ?(3), and Z = 4; Ba(V(2)O(5))(SeO(3)), orthorhombic, space group Pnma (No. 62), a = 13.9287(7) ?, b = 5.3787(3) ?, c = 8.9853(5) ?, V = 673.16(6) ?(3), and Z = 4; Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), orthorhombic, space group Fdd2 (No. 43), a = 25.161(3) ?, b = 12.1579(15) ?, c = 12.8592(16) ?, V = 3933.7(8) ?(3), and Z = 8; Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), orthorhombic, space group Fdd2 (No. 43), a = 25.029(2) ?, b = 12.2147(10) ?, c = 13.0154(10) ?, V = 3979.1(6) ?(3), and Z = 8.  相似文献   

18.
Treatment of CrCl2(THF)2 with NaOSitBu3 afforded the butterfly dimer [(tBu3SiO)Cr]2(mu-OSitBu3)2 (1(2)), whose d(CrCr) of 2.658(31) A and magnetism were indicative of strong antiferromagnetic coupling. A Boltzmann distribution of low-energy 1A1, 3B1, 5A1, 7B1, and 9A1 states obtained from calculations on [(HO)2Cr]2(muOH)2 (1'(2)) were used to provide a reasonable fit of the mu(eff) vs T data. Cleavage of 1(2) with various L (L = 4-picoline, p-tolunitrile, tBuCN, tBuNC, Ph2CO, and PMe3) generated (tBu3SiO)2CrL2 (1-L2). The dimer was oxidatively severed by Ph2CN2 to give (tBu3SiO)2Cr(N2CPh2)2 (2) and by RN3 at 23 degrees C to afford (silox)2Cr=NR (3-R) for bulky R (adamantyl (Ad), 2,6-iPr2-C6H3, 2,4,6-Me3-C6H2 = Mes, 2,6-Ph2-C6H3) and (tBu3SiO)2Cr(=NR)2 (4-R) for smaller substituents (R = 1-Naph, 2-Anth). X-ray structural studies were conducted on 1(2), square planar 1-(OCPh2)2, pseudo-Td 2 and pseudo-trigonal 3-(2,6-Ph2-C6H3), whose S = 1 ground state was discussed on the basis of calculations of (H3SiO)2Cr=NPh (3' '-Ph).  相似文献   

19.
1 INTRODUCTION Recently, the researches on inorganic-organic hy-brid compounds represent an advanced field in mate-rial science[1]. At the molecular level, the combina-tion of two extremely different components providesan avenue to design new hybrid materials as well asthe ability to modulate properties of one or more ofthe components[2~6]. Some attractive properties, suchas efficient luminescence[2~4], ideal thermal and me-chanical stability, interesting magnetic[5], non-linearoptical[…  相似文献   

20.
ElectrochemicalStudyofTrinuclearMetalComplexes[M_3O_2(O_2CCH_3)_6(H_2O)_3]~(2+)(M_3=Mo_3,MoW_2,W_3)LiuHuang;XuLi;HuangJin-Shun;YanD...  相似文献   

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