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1.
用DV-XαSCC方法和自然键轨道法研究了CpBeH和Cp_2Be的电子结构和成键情况,进而根据作者之一提出的共价定义研究了CpBeX(X=H,Cl,Br,CH_3,C≡CH,……)和Cp_2Be等化合物中铍原子的共价.结果表明,在这些化合物中,铍原子的共价均为6.  相似文献   

2.
义祥辉  黎乐民  徐光宪 《化学学报》1995,53(11):1060-1064
用DV-XαSCC方法和自然键轨道法研究了CpBeH和Cp2Be的电子结构和成键情况,进而根据作者之一提出的共价定义研究了CpBeX(X=H, Cl, Br, CH3, C≡CH, ...)和Cp2Be等化合物中铍原子的共价。结果表明, 在这些化合物中, 铍原子的共价均为6。  相似文献   

3.
柳利  陈祖兴  柳士忠  黄维扬 《中国化学》2006,24(8):1020-1025
Soluble platinum(Ⅱ)polyyne polymers trans-{Pt-[P(C_4H_8N)_3]_2(C≡C)_2R(C≡C)_(2-)}_n and trans-{Pt-[P(C_4-H_3O)_3]_2(C≡C)_2R(C≡C)_(2-)}_n(R=9,9-dihexylfluorene-2,7-diyl)have been prepared in good yields by CuI-catalyzedpolymerization involving the dehydrohalogenating coupling of trans-{PtCl_2[P(C_4H_8N)_3]_2} and trans-{PtCl_2[P-(C_4H_3O)_3]_2} with H(C≡C)_2R(C≡C)_2H,respectively.We report the optical spectroscopy of these polyplatinaynes.The influence of the heavy metal atom in these metal alkynyl systems on the intersystem crossing rate and the spa-tial extent of lowest singlet and triplet excitons was systematically characterized.Our investigations indicate that theorganic triplet emissions can be harvested by the heavy-atom effect which enables efficient intersystem crossingfrom the S_1 singlet excited state to the T_1 triplet excited state.  相似文献   

4.
本文研究了[Co(NH_3)_4CO_3]Cl、[Co(en)_2CO_3]C1分别与NH_4SCN在100℃发生的固相取代反应.[Co(NH_3)_4CO_3]Cl与NH_4SCN反应生成trans-[Co(NH_3)_4(NCS)_2]~+;[Co(en)_2CO_3]Cl与NH_4SCN反应先生成cis-[Co(en)_2(NCS)_2]~+,然后转化成trans-(Co(en)_2(NCS)_2]~+。采用气相色谱、红外光谱、X粉末衍射和核磁共振法对相应反应体系及其产物进行了测试,推测反应按S_(N~2)机理进行。  相似文献   

5.
四氯化碳与Zr(NMe_2)_2[~iPr NC(NMe_2)N~iPr]_2(1)反应先生成中间体Zr Cl(NMe_2)_2[~iPr NC(NMe_2)N~iPr]_2(2),然后生成Zr Cl_2[~iPr NC(NMe_2)N~iPr]_2(3)。该反应可能是自由基反应。另外,配合物2可由Zr Cl(NMe_2)_3与二异丙基碳二亚胺~(i )Pr-N=C=N-~iPr反应制备。对配合物2进行了核磁共振(NMR)和元素分析。  相似文献   

6.
合成了5种不同取代基的炔类化合物Mes2HSiC≡CPh(1,Mes=2,4,6-Me3C6H2)、[tBuC(NAr)2]GeC≡CPh(2,Ar=2,6-iPr2C6H3)、[PhC(NtBu)2]SnC≡CPPh2(3)、[HC(CMe)2(NAr)2]Sn C≡CPPh2(4)和[HC(CMe)2(NAr)2]ZnC≡CPPh2(5),研究了这些化合物与B(C6F5)3的反应.在与B(C6F5)3的反应中,1和2均发生1,1-碳硼化反应生成烯烃化合物(Ph)(Mes2HSi)C=C(C6F5)B(C6F5)2 (6)和{[tBuC(NAr)2]Ge}(Ph)C=C(C6F5)B(C6F5)2 (7), 7是一种GeⅡ/B松散Lewis酸碱对化合物;3~5则都发生B(C6F5)3与配体金属基的位置交换、进而配体金属基转换键合PPh2的反应,分别生成新颖的分子内双性离子炔烃化合物[PhC(NtBu)2]SnP(Ph2)C≡CB(C6F5)3 (8)、[HC(CMe)2(NAr)2]SnP(Ph2)C≡CB(C6F5)3(9)、[HC(CMe)2(NAr)2]ZnP(Ph2)C≡CB(C6F5)3 (10).文中还讨论了反应机理.  相似文献   

7.
采用密度泛函理论(DFT)研究了螺桨烷型分子BX[(CH2)n]3和BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的结构、稳定性、化学键和电子光谱性质.计算结果表明这些分子都是稳定的.BX[(CH2)n]3(X=N,P;n=1-6)的最高占据分子轨道(HOMO)和最低空分子轨道(LUMO)之间的能隙均大于5.20 eV,其中BN[CH2]3和BP[CH2]3的能隙超过7.0 eV,与C5H6的能隙(7.27 eV)很接近,BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的能隙在6.80 eV左右.所研究分子能量的二阶差分表明BN[(CH2)3]3、BP[(CH2)4]3及BX(CH2)[CH(CH2)2CH](X=N,P)是最稳定的.BX[(CH2)n]3的Wiberg键级表明除了BN[(CH2)n]3(n=2和6)中不存在B―N键,其它化合物中B和N均形成了化学键,BP[(CH2)n]3中除了BP[(CH2)2]3不存在B―P键,其它的均存在.电子密度的拓扑分析表明N―B键属于离子键,而P―B键具有共价键特征.BX[(CH2)n]3(X=N,P)的第一垂直激发能分别在191.1-284.8 nm和191.8-270.1 nm之间,BX(CH2)[CH(CH2)n CH](X=N,P)的第一垂直激发能分别在190.5-199.7 nm和209.0-221.3 nm之间.  相似文献   

8.
《化学通报》2001,64(9):579-582
用自洽场理论(HF)和密度泛函理论(DFT)的B3LYP方法,在6-31G*的水平上对化合物(HAlNH)2和(HAlNH)3的几何结构进行优化,并分别与环丁二烯C4H4和苯分子C6H6的结构和成键方式进行比较.以B3LYP/STO-3G方法讨论其分子轨道波函数(ψ).结果表明C4H4和(HAlNH)2均为D2h对称,前者为长方形结构,形成两个孤立的π键;而后者为菱形结构,形成一个π44键.C6H6和(HAlNH)3分子点群分别为D6h和D3h,并均形成一个π66键.成键原子对分子轨道的贡献不同,其中C原子是完全等价的,而Al和N原子各不相同,N原子比Al的贡献要大得多.  相似文献   

9.
通过η~5-官能团取代环戊二烯基三羰基铬钠与SOCl_2相作用可制得[η~5-CH_3C(O)C_5H_4Cr(CO)_2]_2S1,[η~5-CH_3O_2CC_5H_4Cr(CO)_2]_2S 2和[η~5-C_2H_5O_2CC_5H_4Cr(CO)_2]_2S 3;将1进一步用NaBH_4还原以及2经皂化、酸化和丙酮重结晶制得[η~5-CH_3CH(OH)C_5H_4Cr(CO)_2]_2S 4和[η~5-HO_2CC_5H_4Cr(CO)_2]_2S·nCH_3C(O)CH_3 5.1—5是首次报道的一类含有机官能团的铬-硫三键化合物。1经X射线单晶结构分析表明,它是由一个硫原子通过三键将2个相同的金属有机碎片η~5-CH_3C(O)C_5H_4Cr(CO)_2连在一起的,其Cr≡S≡Cr结构单元呈线性构型,平均Cr≡S三键键长为2.072。  相似文献   

10.
A new luminescent and thermally stable platinum(Ⅱ) polyyne polymer trans-[-Pt(PBu_3)_2C=CArC=C-]_n(P1) containing the 2,7-fluorene chromophoric spacer substituted by pendant carbazolyl group via long alkyl bridges. The regiochemical structures of these compounds were studied by various spectroscopic analyses.We report the photophysical properties of this group 10 polymetallayne and a comparison was made to its binuclear model complex trans-[Pt(Ph)(PEt_3)_2C≡CArC≡CPt(Ph)(PEt_3)_2](M1) as well as to those ...  相似文献   

11.
[Zn(phen)3]·ZTO·6H2O(1) and[Cu(phen)3]·ZTO·6H2O(2) were synthesized by the reaction of Zn(NO3)2·6H2O/Cu(NO3)2·3H2O with 4,4-azo-1H-1,2,4-triazol-5-one(ZTO) and 1,10-phenanthroline(phen). The two compounds were characterized by elemental analysis and IR spectrum analysis, respectively. Compound 1 was also characterized by single crystal X-ray diffraction analysis. For compound 1, the coordination geometry around the Zn2+ is a distorted octahedron, with the bite angles of 76.7(3)°-77.6(4)° for all three phen ligands. Moreover, the thermal behaviors and thermal decomposition kinetics were studied and analyzed. Besides, thermal stability and safety parameters(TSADT, Tb) are 164.7 and 166.4℃ for compound 1, and 149.6 and 150.8℃ for compound 2, respectively.  相似文献   

12.
<正>过渡金属配位聚合物因其丰富的网络拓扑结构及其在吸附、催化、分子识别、光、电、磁等方面的潜在应用而成为无机化学和材料化学研究领域中  相似文献   

13.
The title calixarene, dimanganese thiacalix[4]arene tetrasulfonate, was prepared and its crystal structure was determined. [Mn(H2O)6]2[thiacalix[4]arene tetrasulfonate]·0.5H2O crystallizes in the monoclinic system, P2(1)/m space group, with a=13.014 (6), b=14.146 (9), c=13.184 (7) Å, β=113.307 (10)°, V=2229 (2) Å3 and Dc=1.710 gcm−3, Z=2. The title calixarene exists in the solid state as bilayer structure. The hydrophobic organic layer consists of thiacalix[4]arene tetrasulfonate in an up-down fashion, whereas, the hydrophilic inorganic layer consists of hexaaquamanganese (II) which is linked to the former through a second-sphere coordination.  相似文献   

14.
The IR and Raman spectra of [(CH3)3NH]3Sb2Cl9 (A), [(CH3)3NH]3Bi2Cl9 (B) and two of their mixed crystals containing respectively 33% (AB.33) and 42% Bi (AB.42) are analyzed and compared. A and AB.33 show ferroelectric–paraelectric phase transition at 364 K and 344 K, respectively. AB.42 and B are paraelectric in the temperature range between 90 and 365 K. Most of the vibrational modes show continuous changes, with the temperature, in the IR frequencies or intensities with no soft mode behavior. However, characteristic ν(NHCl) and δ(NHCl) vibrations of weakly hydrogen-bonded species are only observed in A and AB.33 below the temperature of the phase transition and are related to the ferroelectricity. The evolution of the IR spectra with the temperature suggests that the ferroelectric properties are connected with the reorientation of the cations which needs a breaking of the weak NHCl hydrogen bonds in the paraelectric phase.  相似文献   

15.
The fluorocarbon soluble, binuclear ruthenium(I) complexes [Ru(μ-O2CMe)(CO)2LF]2, where LF is the perfluoroalkyl substituted tertiary phosphine, P(C6H4-4-CH2CH2(CF2)7CF3)3, or P(CH2CH2(CF2)5CF3)3, were synthesized and partition coefficients for the complexes in fluorocarbon/hydrocarbon biphases were determined. Catalytic hydrogenation of acetophenone to 1-phenylethanol in benzotrifluoride at 105 °C occured in the presence of either [Ru(μ-O2CMe)(CO)2P(C6H4-4-CH2CH2(CF2)7CF3)3]2 (1) or [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 (2). The X-ray crystal structure of [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 was determined. The compound exhibited discrete regions of fluorous and non-fluorous packing.  相似文献   

16.
The compound [Mn2(CO)10] reacts with 2-(Methylthio)thiophene (C5H6S2) while refluxing in xylene to afford a methylthio-tetramanganese product [MnS(CO)3]4, in which C5H6S2 is cleaved with loss of thiophene. The crystal structure of [MnS(CO)3]4 has been studied by direct method. Based on the 21 685 unique reflections collected using Mo of X-ray radiation and a CCD-based detector, it is refined to an agreement index (R1) of 0.079 0. The cell is triclinic with dimensions: a=1.719 49 nm, b=1.959 2 nm, c=2.632 6 nm and α=79.733°, β=71.407°, γ=89.387°. There are 12 unit cells of [MnS(CO)3]4 in the cell, with space group P1.  相似文献   

17.
An X-ray crystal structure determination for the bimetallic complex Mn2(CO)8-[P(NMe2)3]2 reveals that the P(NMe2)3 ligands are trans to the Mn---Mn bond and the Mn---Mn bond distance is relatively long, 2.946(1) Å.  相似文献   

18.
~(186,188)Re具有优良的核素性质,是放射性治疗药物的首选核素之一~([1]).~(186,188)Re广泛用于有机小分子化合物,单抗(McAb)、单抗片段(Fab)、受体配基和生物小分子肽,以达到靶向治疗的目的~([2-3]).铼的化学性质与锝极其相似,在标记前以~(188)ReO_4~-形式存在,在标记药物中呈低价态.制备时常规方法是将七价铼通过亚锡法还原到五价~([4-5]).  相似文献   

19.
单斜Li3V2(PO4)3/C复合材料的制备及其电化学性能   总被引:1,自引:0,他引:1  
以LiOH·H2O、V2O5、H3PO4和蔗糖为原料,采用软化学法制备了锂离子电池正极材料Li3V2(PO4)3/C.通过X射线衍射(XRD)、扫描电镜(SEM)对产物的结构和形貌进行表征,采用恒电流充放电、电化学阻抗考察了产物的电化学性能.结果表明.当煅烧温度达到700℃时,杂质相衍射峰消失,所得的样品为纯相的单斜Li3V2(PO4)3.颗粒粒度为1~2 μm;在3.0~4.5 V电压范围内以0.2C倍率充放电,首次放电比容量达到148.2 mAh·g-1,第50次循环比容量仍为144 mAh·g-1,容量保持率为97%,具有良好的循环性能;另外,样品还具有很好的倍率性能和高温性能.  相似文献   

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