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1.
The structure of a binuclear cadmium(II) quaternary complex, [Cd2(phen)2- Q2(BP)]n 1 (phen = 1,10-phenanthroline, BP = biphenyl-4,4--dicarboxylic acid, Q = 8-hydroxy- quinoline-anion), has been determined by X-ray crystallography and characterized by elemental analysis, IR spectrum and thermogravimetric analysis.It crystallizes in the monoclinic system, space group P21/n with a = 13.1906(18), b = 10.9623(15), c = 16.947(2) -, β = 111.3430(10)°, V = 2282.5(5) -3, Z = 4, Mr = 556.85, Dc = 1.620 g/cm3, F(000) = 1116, μ = 0.994 mm-1 and S = 1.056.In the structure, 1D chains are connected via biphenyl-4,4--dicarboxylic acid, 8-hydroxy quinoline anion and binuclear cadmium atoms into an infinite 1-D molecular chain architecture.Via aryl ring π-π stacking interactions a supramolecular structure is formed in 1.  相似文献   
2.
The structure of a manganese(Ⅱ) polymer,[Mn(TP)(TBZH)]2n 1(TBZH=thiabendazole,TP=terephthalic acid),has been determined by X-ray crystallography and characterized by elemental analysis,IR spectrum and thermogravimetric analysis.It crystallizes in the orthorhombic system,space group Pbcn with a=12.7813(12),b=10.7544(10),c=20.1270(19) ,V=2766.6(4)3,Z=8,C14H9Mn0.50N3O2S,Mr=310.77,Dc=1.492g/cm3,F(000)=1268,μ=0.674 mm-1 and S=1.064.The 1-D chain architecture of 1 is constructed from terephthalic acid and manganese atoms.Hydrogen bonds and aryl ring π-π stacking interactions in 1 contribute to form a 3-D supramo-lecular structure.  相似文献   
3.
The title complex,[(BBI)Mn(BDC)]n 1(BBI = 2,2'-bisbenzimidazole(C14H10N4),BDC=benzene-1,3-dicarboxylate dianion(C8H10O4)),crystallizes in the monoclinic system,space group C2/c,with a=17.822(8),b=16.181(7),c=13.355(6),β=92.112(5)°,V=3848.67(304)3,Z=8,C22H14MnN4O4,Mr=453.31,Dc=1.565 g/cm3,F(000)=1848,μ=0.725 mm-1,S=1.000,the final R=0.0310 and wR=0.0589.1 contains hydrogen bonds and π-π stacking interactions between the neighboring aryl-ring of BBI's,which helps to form a three-dimensional crystal structure.  相似文献   
4.
Gao GG  Xu L  Qu XS  Liu H  Yang YY 《Inorganic chemistry》2008,47(8):3402-3407
The reaction of molybdates with multicarboxylic ligands resulted in the crystalline materials of [Na 8(Mo (VI) 10O 32EDTA)(H 2O) 35] n ( 1) and (NH 4) 8 n [Mo (VI) 10O 32PDTA] n (H 2O) 30 n ( 2) (EDTA = 1,2-diaminoethanetetraacetate; PDTA = 1,3-diaminopropanetetraacetate). In the two compounds, decamolybdate clusters are covalently linked by multicarboxylic ligands to form unusual meso-helical chains. For the first time, the synthesis of an organopolyoxometalate polymer is realized in aqueous media, which opens a green chemical approach to the fabrication of polyoxometalate-based polymers. The photochromic properties of 1 in the poly(vinyl alcohol) film displayed reddish-brown coloration upon UV irradiation, providing a new coloration material for photochromic films.  相似文献   
5.
郝娟  周广刚  马跃  黄文奇  张鹏  卢贵武 《物理学报》2016,65(11):113101-113101
高温压电晶体是许多机电器件必需的一种多功能材料, Ga3PO7晶体的居里温度高达1364 ℃, 可应用于高温极限条件. 但是预测高温极限条件下晶体的结构以及物理性质的问题采用实验研究的手段非常困难, 而理论上的预测未见研究. 本文采用密度泛函-准谐振近似理论计算了温度在0-1200 ℃范围内Ga3PO7 晶体的结构常数和热学性质, 结果表明Ga3PO7晶体的晶格常数a和c随温度的升高呈线性增大, 且c方向受温度影响更为显著; 晶体的密度随温度的升高而减小, 计算的a 和c方向平均热膨胀系数分别为1.67×10-6 K-1和3.58×10-6 K-1, 高温区定压热容为2.067 J/g·K, 与实验值一致. 计算了从常温到高温下该晶体的弹性常数以及体弹性模量的变化, 研究了高温条件下的声表面波特性, 发现随着温度的升高, 声表面波速度浮动较小, 而机电耦合系数略有增大; 在传播角为151° 时该晶体具有较好的温度稳定性且机电耦合系数达到最大值, 这表明Ga3PO7 晶体是一种有望应用于高温环境下的压电晶体.  相似文献   
6.
A new metal-organic complex Mn2(cbba)4(phen)2 (Hcbba = 2-(4'-chlorine-benzoyl)-benzoic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound crystallizes in orthorhombic, space group Pbcn with a = 12.154(5), b = 18.166(7), c =31.197(13) (A°), V = 6887(5) (A°)3, C80H48C14Mn2N4O12, Mr= 1508.90, Dc = 1.455 g/cm3, μ(MoKa) =0.591 mm-1, F(000) = 3080, Z = 4, the final R = 0.0408 and wR = 0.0873 for 4033 observed reflections (I > 2σ(I)). In the crystal structure, the manganese atom is six-coordinated with four carboxylate oxygen atoms from three different cbba ligands and two nitrogen atoms from phen ligands, showing a distorted octahedral geometry. Furthermore, it exhibits a 3D supramolecular network through π-π interactions.  相似文献   
7.
周广刚  卢贵武  矫玉秋  李英峰  王坤  于养信 《物理学报》2012,61(1):10204-010204
通过构建晶体表面-KDP分子界面吸附结构模型, 采用分子动力学和密度泛函计算方法研究KDP分子在(001)和(010)面吸附的物理化学过程, 考察了温度对物理吸附行为的影响. 研究表明: KDP晶体表面的吸附过程和生长习性主要由化学吸附主导, 化学吸附能的计算表明[K-O8]基元在(001)界面的结合能是(010)界面结合能的2.86倍; 在饱和温度附近, [H2PO4]-阴离子在KDP界面的物理结合能随温度的变化呈现振荡特征, 溶液中有较多的离子团簇形成, 溶液变得很不稳定; 当温度从323 K降低至308 K时, 水分子在界面的结合能总体呈下降趋势, 而KDP分子在界面的吸附能总体呈上升趋势, 脱水过程是水分子和[H2PO4]-阴离子在固液界面边界层竞争吸附的结果. 研究结果对确足晶体生长界面动力学过程发展和完善晶体生长理论有重要意义. 关键词: 分子动力学 双层结构模型 结合能  相似文献   
8.
李秀梅  王庆伟  李丹  赵霞  高广刚 《结构化学》2007,26(11):1341-1344
A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction,elemental analyses and IR spectroscopy. The compound {[Cu2(C2O4)2(inta)4](inta)}n1 crystallizes in the triclinic system,space group P1,with a=8.4722(5),b=10.9825(6),c=11.6128(6),α=104.8050(10),β=102.5740(10),γ= 109.6890(10)o,V=927.18(9)3,Mr=929.79,Z=1,Dc=1.665 g/cm3,F(000)=475,μ=1.231 mm-1,R=0.0453 and wR=0.1185 for 3290 observed reflections (I > 2σ(I)). Of the compound,the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2(C2O4)2}∞ chain is formed along the c axis. Furthermore,the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels (ca. 5.491×11.507) where inta molecules are filled.  相似文献   
9.
A totally structure-determined organosilver(I) metal-oganic framework(MOF) of [{Ag_(18)(CF_3COO)_(18)(H_2O)_2}{Ag_4(erlotinib)_4}]_n·7nCH_3OH·3nH_2O(1) was first synthesized by the self-assembly of erlotinib drug ligand and silver salts in the study. 1 formed a NbO-like 3D network, which was built from Ag(I)-erlotinib induced chains and 18-core silver(I) nanoclusters. When 1 was dispersed in methanol solution, it formed derivative nanoparticles(1-NPs) with the average size of 3.81 nm. Silver(Ⅰ) ion is an efficient reactive oxygen species(ROS) evocator, whereas the erlotinib ligand possesses the targeting activity towards tumor cells. Therefore, IC_(50) values of 1-NPs for A549 and MRC-5 cells were respectively 0.97 and 7.28 μM, which were lower than IC_(50) value of erlotinib. It should be noted that the 7.5-fold higher inhibition effect on A549 cells allows 1-NPs to be a potential targeting anticancer drug for curing lung cancer. The study opens a new avenue to design anticancer drugs based on organosilver(I)MOF derivatives that can realize the value-added reactivity by combining clinical drugs with ROS-inductive silver(Ⅰ) ion.  相似文献   
10.
Liu H  Qin C  Wei YG  Xu L  Gao GG  Li FY  Qu XS 《Inorganic chemistry》2008,47(10):4166-4172
Two sandwich-type complexes Na9n(Cu(im)4(H2O)2)1.5n(Cu(im)4(H2O))n[{Cu(im)4}{Na(H2O)2}3{Cu3(im)2(H2O)}(XW9O33)2]2n .(xH2O)n (im=imidazole, X=Bi (1), Sb(2), x=42.5 (1), 40 (2)) have been synthesized and structurally characterized. Basic frameworks of 1 and 2 are built from sandwich-type [{Na(H2O) 2} 3{Cu3(im)2(H2O)}(XW9O33)2](9-) (X=Bi or Sb) anions and [Cu(im) 4](2+) cations. The Cu(2+) and Na(+) ions in the central belt are coordinated by alpha-[XW9O33](9-) units, im, and water molecules to form {CuO4(im)}, {CuO4(H2O)}, and {NaO4(H2O)2} groups in which Cu (2+) ions are partially modified with im ligands. These groups connect alternately forming a six-membered ring including six alpha-[XW9O 33](9-) units. Neighboring anions are further linked by [Cu(im) 4](2+) cations to display an unprecedented anionic chain, which is first observed in sandwich-type tungsto-bismuthate (-antimonite) system. Two kinds of isolated copper complexes and sodium ions are located as counterions, which cause three-dimensional packings of 1 and 2 to present interesting cage structures. The magnetic properties for 1 and 2 both indicate dominant antiferromagnetic interactions among trinuclear Cu(II) clusters.  相似文献   
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