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1.
合成了4,5-二氮芴-9-酮(dafo)的Cu(Ⅱ), Zn(Ⅱ)配合物[Cu(dafo)2(H2O)2] (NO3)2和[Zn(dafo)2 (H2O)2] (NO3)2,通过单晶X射线衍射法确定了它们的结构.晶体结构分析表明,配合物分子中Cu(Ⅱ), Zn(Ⅱ)分别和来自两配体的四个氮原子及两个水分子中的氧原子配位,处于六配位的配位环境中,两配体基本处于同一平面,两水分子垂直于两配体所在平面,Cu(Ⅱ)处于畸变八面体中心,Zn(Ⅱ) 处于正常八面体中心,对两种配合物进行了元素分析、红外和热分析表征,在实验的基础上,采用Gaussian-98w中的DFT-B3LYP/LANL2DZ对两种配合物进行了全几何优化以及后续计算.  相似文献   

2.
第ⅢA族金属叠氮多聚体结构和性质的理论研究   总被引:1,自引:0,他引:1  
在DFT-B3LYP/SDD水平上计算研究了第A族金属叠氮多聚体(Me2MN3)n(n=1~3,M=Ga,Al)的结构和性质.多聚体(Me2MN3)2,3的各优化构型均为环状,通过一子体系叠氮基的α-N和另一子体系的金属Ga或Al相连.二聚体(Me2MN3)2中含M2N2平面四元环结构,三聚体(Me2MN3)3具有结合能相近的扭船式和椅式两种构象,均含M3N3六元环结构.与单体相比,多聚体的几何参数变化较大.报道了它们在不同温度下的热力学性质,发现叠氮二甲基镓和铝体系以二聚体形式存在.  相似文献   

3.
陈玉红  任宝兴  曹一杰 《化学学报》2010,68(18):1793-1801
利用密度泛函理论在B3LYP/6-311G*水平上对碱土金属叠氮化合物(CaN6)n (n=1~5)团簇各种可能构型进行了几何优化, 预测了各团簇的最稳定结构. 并对最稳定结构的成键特性、电荷分布、振动特性及稳定性进行理论研究. 结果表明, 叠氮化合物中叠氮基以直线型存在, CaN6团簇的最稳定结构为线型结构, (CaN6)n (n=2~5)团簇首先由两个叠氮基与两个Ca原子构成一个近似菱形, 再由菱形相互垂直形成链状最稳定结构; 叠氮基中间的N原子显示正电性, 两端的N原子显示负电性, 且与Ca直接作用的N原子负电性更强, 金属Ca原子和N原子之间形成很强的离子键; (CaN6)n (n=1~5)团簇最稳定结构的IR光谱分为4个部分, 其最强振动峰均位于2195~2280 cm-1, 振动模式为叠氮基中N-N键的反对称伸缩振动; 稳定性分析显示, (CaN6)3和(CaN6)5团簇相对于其他团簇较为稳定.  相似文献   

4.
采用密度泛函理论(DFT)研究了杂原子M(M=Li, Na, K, Be, Mg, Ca, C和Si)在B/N单空位缺陷处的掺杂对(6,0)BN纳米管体系非线性光学性质的影响. 采用B3LYP方法共得到了14种几何构型, 并采用BHandHLYP方法计算了这些结构的第一超极化率β0值. 研究结果表明, 单纯的B或N缺陷几乎不影响BN纳米管体系的非线性光学性质; 与B缺陷处掺杂的体系相比, 杂原子在N缺陷处的掺杂更有利于提高BN纳米管体系的第一超极化率β0值; 对于同周期掺杂原子, 还原性越强的原子掺杂对BN纳米管体系的第一超极化率β0值的改善越明显, 表现为β0(Ⅰ族)>β0(Ⅱ族)>β0(Ⅳ族); 对比同主族掺杂原子, 第三周期元素Na和Mg的掺杂能更有效地提高体系的第一超极化率β0值, 原因主要在于原子半径和还原性等因素共同决定其对BN纳米管体系第一超极化率β0值的改善程度. 本文研究结果为有效提高BN纳米管体系的非线性光学性质提供了一种新思路, 为基于BN纳米管的非线性光学材料设计提供了有价值的理论信息.  相似文献   

5.
采用密度泛函理论方法, 计算分析了系列12顶点碳硼烷Ni(Ⅱ)配合物的非线性光学(NLO)性质和电子光谱. 结果表明, 2个P(CH3)3配体的结构变化对配合物的原子间距离影响较小, Ni(Ⅱ)配合物的极化率随取代基共轭性和空间体积的增加而增大. 增强配合物的共轭性及改变P(CH3)3配体结构对二阶NLO系数有明显影响, 其中取代基为苯胺的配合物5b的第一超极化率总有效值(βtot)最大. 分析配合物的电子光谱和相应的分子轨道组成可知, 配体内的电荷转移以及配体到金属的电荷转移对二阶NLO系数贡献较大.  相似文献   

6.
利用线性溶剂化能相关(LSERs)方法对聚(乙基苯乙烯-二乙烯基苯)包覆钛胶固定相(ES-DVB-TiO2)的保留行为进行评价,并与聚丁二烯涂覆钛胶固定相(PBD-TiO2),键合硅胶固定相(ODS)和树脂固定相(PR-1)作了比较,计算出各变最对logk'的百分方差数,发现V2、Σα2H,和Σβ2H对logk'有较大的贡献,与聚合物固定相PRP-1近似,因此它们有相似的保留机理,即吸附机理大于分配机理.  相似文献   

7.
利用密度泛函理论在B3LYP/6-311G*水平上对叠氮化合物(HCaN3)n (n=1~5)团簇各种可能构型进行了几何优化, 预测了各团簇的最稳定结构. 并对最稳定结构的成键特性、电荷分布、振动特性及稳定性进行理论研究. 结果表明, HCaN3团簇最稳定结构为折线型, (HCaN3)n (n=2~4)团簇最稳定结构为叠氮基端位N原子与Ca原子相互链接形成平面环状结构, (HCaN3)5团簇最稳定结构为立体钟形结构. 团簇最稳定结构中金属Ca原子均显示正电性, H原子均显示负电性, 叠氮基中间的N原子显示正电性, 叠氮基两端的N原子显示负电性, 且和Ca原子直接作用的N原子的负电性更强. Ca-N键和Ca-H键为典型的离子键, 叠氮基内N原子之间是共价键. 最稳定结构的IR光谱主要分为3个部分, 其最强振动峰均位于2193~2302 cm-1段, 振动模式为叠氮基中N-N键的反对称伸缩振动. 叠氮基在团簇和晶体中结构不变, 始终以直线型存在, 说明金属叠氮化合物团簇可以很好地模拟其晶体的局域成键和局域电荷转移等特性. 稳定性分析显示, (HCaN3)3团簇相对于其他团簇更稳定.  相似文献   

8.
三(3-羟基黄酮)合铝(Ⅲ)的合成及晶体结构   总被引:3,自引:0,他引:3  
合成了三(3-羟基黄酮)合铝(Ⅲ),制得[Al(C15H9O3)3]2·2CHCl3·8H2O晶体,X射线衍射结果表明:其结构属于三方晶系,空间群为R3.晶胞参数:a=b=1.6558(3)nm,c=3.6465(20)nm,α=β=90°,γ=120°,V=8.65608(0.00586)nm3,Dc=1.45g/cm3,μ(MoKα)=3.20cm-1,F(000)=3924.分子中每个3-羟基黄酮以其独特的酮基和羟基同时与Al3+配位,3个配体中的6个配位氧原子形成扭曲的配位八面体.  相似文献   

9.
在离子液体BMImPF6中, 用不同的钯催化剂和Lewis酸三氟甲磺酸铜Cu(OTf)2共催化苯乙烯二聚反应, 发现用Pd(OAc)2/Cu(OTf)2作催化剂, Pd/Cu物质的量之比为1~4时, 可高产率高选择性地获得苯乙烯二聚产物1,3-二苯基-1-丁烯. BMImPF6对催化剂有较好的溶解性, 可固定催化剂体系, 使催化剂有效地与产品分离. 同时, α-甲基苯乙烯的二聚反应表明, 室温下不发生反应, 提高温度有利于反应进行.  相似文献   

10.
测定了(p-CH3OC6H4)2TeO存在下M2(CO)10(M=Mn,Re)的CO取代反应速率及活化参数。其表观速率常数分别与M2(CO)10和(p-CH3OC6H4)2TeO的浓度的一次方成正比。本文所建议的缔合机理与前人用(CH3)3NO作氧原子转移试剂的相应反应所提出的机理相似。讨论了在(CH3)3NO和(p-CH3OC6H4)2TeO存在下影响M2(CO)10的CO取代反应速率的因素。  相似文献   

11.
The hexaaquacobalt(II)bis(phthalhydrazidato)tetrahydrate, [Co(H2O)6](C8N2O2H5)2·4H2O is examined using single crystal X-ray diffraction analysis. The crystals are triclinic, space group , with a = 9.757(1), b = 10.955(2), c = 11.106(1),  = 100.79(2), β = 90.35(3), γ = 91.54(1) and Z = 2. In [Co(H2O)6](C8N2O2H5)2·4H2O, the cobalt(II) is coordinated by six water ligands and the [Co(H2O)6]2+ is associated with the two O-deprotonated phthalhydrazidato ions only by hydrogen bonds. The infrared and Raman spectra of phthalhydrazide (PH) and infrared spectra of deuterated derivative phthalhydrazide (PD) and of [Co(H2O)6](C8N2O2H5)2·4H2O are reported. The theoretical wavenumbers, infrared intensities and Raman scattering activities have been calculated using density functional (B3LYP) method with the 6-311++G(d,p) basis set. The calculated potential energy distribution has proved to be of great help in assigning the spectra PH, its deuterated derivative and [Co(H2O)6](C8N2O2H5)2·4H2O. The results from natural bond orbital (NBO) analysis for keto-hydroxy form of PH are presented.  相似文献   

12.
铁氰根桥联的一维链状大环配位聚合物的合成及结构   总被引:1,自引:1,他引:0  
配位聚合物的合成、结构和性质研究近年来引起了人们极大的兴趣 ,已成为配位化学最活跃的研究领域之一 .由于 [Fe( CN) 6 ]3- 和 [Fe( CN) 6 ]4- 离子本身具有丰富的配位特性 ,可与金属离子及其配合物形成一维链状、二维网状和三维立体结构的配位聚合物 [1~ 5] ,铁氰根和亚铁氰根桥联的配位聚合物的研究成为其中的研究热点之一 .此外 ,铁氰根和亚铁氰根桥联的配位聚合物具有较高的铁磁相变温度[6~ 8] ,是一类具有较好应用前景的分子磁体 .但是 ,以金属大环配合物作为结构单元与 [Fe( CN) 6 ]3-和 [Fe( CN) 6 ]4-离子形成的配位聚合物…  相似文献   

13.
Three novel compounds, [Co(en)3]2[Zr2(C2O4)7]·2H20(HNU-2, en=ethylenediamine), [Co(NH3)6]· [Ce(CzO4)3(H2O)]·H2O(HNU-3) and [Co(dien)2][Gd(C2On)3]·0.75H2O(HNU-4, dien=dethylenetriamine) were hydro- thermal synthesized based on the templates of [Co(en)3]C13, [C0(NH3)6]C13 and [Co(dien)2]C13, respectively. The Zr4+ Ce3+ and Gd3+ cations are all coordinated by four oxalates to form [M(C2O4)n(H2O)n]m (M=Zr, Ce or Gd; n=0 or 1; m=4 or 5), which are similar to [In(C2O4)4]5- in NKB-1, and can be regarded as 4-connected building units. The [M(C2O4)a(H2O)n]m units are connected via sharing the bis-bidentate bridging oxalate ligands to form binuclears in HNU-2 and 1D "zigzag" chains in HNU-3 and HNU-4. cular building units to design 3D open frameworks with It is suggested that these compounds could be used as mole- zeolite topologies.  相似文献   

14.
Five transition metal coordination compounds, [Mn2(8-qoac)2(bdc)(H2O)4](1)(8-qoacH=quinoline-8-oxy- acetate acid, H2bdc=benzene-1,4-dicarboxylic acid), [Zn4(8-qoac)4(bdc)2]n(2), {[Cd2(8-qoac)2(Hip)2(H2O)2]· (H2O)4}n(3)(H2ip=benzene-1,3-dicarboxylic acid), [Pb3(8-qoac)2(bdc)1.5(H2O)Cl]n(4) and [Zn2(8-qoac)(8-ql)(bdc)]n (5)(8-Hql=8-hydroxyquinoline), were synthesized by hydrothermal syntheses of metal salts with benzenedicarboxy- lic acid and 8-qoacH. Compound 1 possesses a discrete dimer bridged by bdc2- ligand. Compound 2 presents a 2D layer network constructed from bdc2- linkers and 1D infinite ribbons, in which Zn(II) centers are bridged by 8-qoac- with a tetradentate binding mode. Compound 3 displays a 1D zigzag chain, with adjacent chains further connected via extensive O-H···O hydrogen bonds to generate a 3D supramolecular structure. Compound 4 shows a 3D framework containing trinuclear lead secondary building units and bdc2- linkers, in which a new coordination mode of 8-qoac- ligand is observed. In compound 5, Zn(II) ions are simultaneously bridged by 8-qoac-, 8-ql- and bdc2- ligands to form tetranuclear zinc units, which are further interlinked by bdc2- linkers to yield a 2D wave-like layer. Based on intraligand(IL)(π-π*) fluorescent emission, compounds 1―5 possess strong purple fluorescent emissions. In addition, the thermal stabilities of compounds 1―5 were studied.  相似文献   

15.
The complexation of 4-nitrocatechol in aqueous solution at pH 5 has been studied by molecular spectroscopy combined with quantum chemical calculations. In these physico-chemical conditions, the formation of the two complexes [4ncatAl(H2O)4]+ and [(4ncat)2Al(H2O)2] has been highlighted. The electronic absorption spectra of the 1:1 and 1:2 complexes of Al(III) with 4-nitrocatechol have been computed using the time-dependent density functional theory and the polarizable continuum model. It turns out that the 6-311+G(d,p) basis set provides a good agreement between experimental and theoretical absorption spectra. This good agreement has allowed the determination of the preferential conformation of the 1:2 complex in aqueous solution. A complete assignment of the UV–Vis absorption and Raman spectra of the complexes has been proposed.  相似文献   

16.
Excitation of solutions of Fe(bipy)2(CN)2 by a 266-nm laser pulse produces a hydrated electron and the oxidized complex, Fe(bipy)2 (CN)2+, in the primary photochemical step, in homogeneous aqueous solution as well as in aqueous solutions containing cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) micelles. In all cases nascent hydrated electrons react with ground state Fe(bipy)2(CN)2 to form Fe(bipy)2(CN)2, and comparison of the decay constants in the three media (H2O: k = 2.8 × 1010 M−1 s−1; CTAB: k = 2.9 × 1010 M−1 s−1; SDS: k = 5.5 × 109 M−1 s−1), shows that the reaction is essentially unaffected by CTAB micelles but is much slower in SDS solution. Similar micellar effects were found for the back reaction between eaq and Fe(bpy)2(CN)2+. Rate constants for the scavenging of the photogenerated hydrated electrons by methyl viologen (MV2+) cations and NO3 anions were measured in the three systems, and the results indicate that for scavenging by MV2+ the rate constants are decreased in the micelle systems (k in H2O, 8.4 × 1010; CTAB, 3.5 × 1010 and SDS, 1.58 × 1010 M−1 s−1), whereas for NO3 the CTAB micelle decreases while the SDS micelle enhances the scavenging compared to water solution (k in H2O, 8.3 × 109; CTAB, 7 × 108; and SDS, 2.05 × 1010 M−1 s−1). For the comproportionation reaction between Fe(bipy)2(CN)2+ and Fe(bipy)2(CN)2 both micelles reduce the rate (k in H2O, 3.3 × 1010; CTAB, 2.3 × 1010; and SDS, 1.05 × 1010 M−1s−1), but while the reaction of Fe(bipy)2(CN)2+ with MV+ is increased in CTAB compared to water, it is slowed in SDS (k in H2O, 2.4 × 1010; CTAB, 8.9 × 1010; and SDS, 1.8 × 1010 M−1s−1). All effects observed in these microheterogeneous systems can be uniformly interpreted in terms of Coulombic interactions between the actual reactants and the charged surface of the micelles.  相似文献   

17.
Thermal decomposition of mixed ligand thymine (2,4-dihydroxy-5-methylpyrimidine) complexes of divalent Ni(II) with aspartate, glutamate and ADA (N-2-acetamido)iminodiacetate dianions was monitored by TG, DTG and DTA analysis in static atmosphere of air. The decomposition course and steps of complexes [Ni(C5H6N2O2)(C4H5NO4)2−(H2O)2]·H2O, [Ni(C5H6N2O2)(C5H7NO4)2−(H2O)2]·H2O and [Ni(C5H6N2O2)(C6H8N2O5)2−(H2O)2]·1.5H2O were analyzed. The final decomposition products are found to be the corresponding metal oxides. The kinetic parameters namely, activation energy (E*), enthalpy (ΔH*), entropy (ΔS*) and free energy change of decomposition (ΔG*) are calculated from the TG curves using Coats–Redfern and Horowitz–Metzger equations. The stability order found for these complexes follows the trend aspartate > ADA > glutamate.  相似文献   

18.
选择柔性的双吡啶双酰胺配体N,N'-双(3-吡啶甲酰胺基)-1,2-乙烷(3-bpye)、钼酸铵和氯化锌在水热条件下自组装制备了一个基于一维[H_2Mo_4O_(14)]_n~(2n-)链的三维锌配合物[Zn(3-bpye)(H_2Mo_4O_(14))(H_2O)_2],并通过元素分析、红外光谱、热重分析等技术手段研究了配合物的结构,并利用X射线单晶衍射分析进行了晶体结构表征。结构解析揭示标题配合物是三斜晶系,P-1空间群,晶胞参数a=0.61310(3)nm,b=1.04750(6)nm,c=1.06540(6)nm,α=78.5540(10)°,β=77.5350(10)°,γ=89.9050(10)°,V=0.65420(6)nm~3,M_r=981.47,D_c=2.491 g/cm~3,Z=1,F(000)=468,R_1=0.0290,ωR_2=0.1068。标题配合物中,金属锌离子连接一维[H_2Mo_4O_(14)]_n~(2n-)链形成一种二维无机双金属层[Zn(H_2Mo_4O_(14))]_n,相邻的层间又通过双齿配体3-bpye连接形成三维CdSO_4拓扑的骨架结构。配合物表现出强的荧光发射特性,而且其在紫外光照下对亚甲基蓝和罗丹明B均有明显的催化降解活性。  相似文献   

19.
A novel N6 macrocyclic ligand, L1 (2,8,14,20-tetramethyl-3,7,15,19,25,26-hexaaza-tricyclo[19.3.1.19,13]hexacosa-1(24),9,11,13(26),21(25),22-hexaene), was obtained by reduction of the 2 + 2 condensation product of 2,6-diacetylpyridine and propane-1,3-diamine. Zinc(II) complexes of L1, of a related N8 macrocycle, L3 (3,6,9,17,20,23,29,30-octaaza-tricyclo[23.3.1.1[11,15]]triaconta-1(28),1,13,15(30),25(29),26-hexaene), similarly prepared by 2 + 2 condensation of 2,6-diformylpyridine and diethylenetriamine and of a tetra N-2-cyanoethyl derivative of a homologue of L1 prepared from diformyl pyridine and ethane-1,2-diamine, L2 (3-[6,14,17-tris-(2-cyano-ethyl)-3,6,14,17,23,24-hexaaza-tricyclo[17.3.1.18,12] tetracosa-1(23),8(24),9,11,19,21-hexaen-3-yl]-propionitrile), were prepared. Structures were determined for [ZnL1](ClO4)2 · H2O, [ZnL2](NO3)2 and [Zn2L3(NO3)2](NO3)2 · H2O. The [ZnL1](ClO4)2 · H2O and [ZnL2](NO3)2 complexes present a mononuclear endomacrocyclic structure with the metal in an octahedral distorted environment coordinated by the six donor nitrogen atoms from the macrocyclic backbone while the complex [Zn2L3(NO3)2](NO3)2 · H2O is dinuclear with both metal atoms into the macrocyclic cavity coordinated by four donor nitrogen atoms from the macrocyclic framework and one oxygen atom from one monodentate nitrate anion, in a distorted square pyramidal arrangement.  相似文献   

20.
金属磷酸盐材料在吸附、离子交换、离子传导和催化剂方面有潜在的应用前景[1~5]. 近年来, 通过水热反应合成了一些A-V-P-O化合物. 在这些化合物中, A一般为碱金属或有机阳离子, 如层状结构的[H2N(C4H8)2NH2][(VO)4(OH)4(PO4)2][6] 和[H2N(C2H4)3NH2][(VO)8(HPO4)3(PO4)4*(OH)2]*2H2O[6], 一维链状结构的 [H2NCH2CH2NH3(VO)(PO4)][7], 手性双螺旋结构的 [(CH3)2NH2]K4[(VO)10(H2O)2(OH)4(PO4)7]*H2O[8]以及具有三维骨架结构的化合物 [H3N(CH2)3NH3K(VO)3(PO4)3][9], [H3N(CH2)3NH3]2[V(H2O)2(VO)6(OH)2(HPO4)3(PO4)5]*3H2O[10]和[H3N(CH2)2NH3][(VO)3(H2O)2(PO4)2(HPO4)4][11].  相似文献   

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