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排序方式: 共有135条查询结果,搜索用时 15 毫秒
61.
合成了一个新的配位聚合物[Ni(p-CPOA)(2,2′-bipy)(H2O)]n(p-CPOA2-= 4-羧基苯氧乙酸根,2,2′-bipy= 2,2′-联吡啶),并对其进行了元素分析、红外和单晶X-射线的表征.结果表明:配合物的化学式为C19H16N2O6Ni,晶体属单斜晶系,空间群为C2/c,晶胞参数a = 14.254(3),b = 13.085(3),c = 19.372(4)A,β = 104.89(3)°,V = 3491.8(12)A3,Z = 8,Mr = 427.05,Dc = 1.625 g/cm3,μ = 1.153mm-1,F(000) = 1760,最终R = 0.0345,wR = 0.0565。Ni原子为扭曲的六配位八面体构型,每个p-CPOA2-配体桥联2个Ni原子形成一维折叠链状结构,Ni…Ni原子之间的距离为9.675A,且通过分子间氢键将一维链连接成双链结构. 相似文献
62.
63.
A 2D copper coordination polymer of [Cu2(3-PyOH)2(EDTA)]n (EDTA4-=ethylenediaminetetraacetate quadrivalent anion C10H12N2O8, 3-PyOH=3-hydroxypyridine) was synthesized and characterized by the element analysis, IR and single crystal X-ray diffraction. The title complex crystallizes in monoclinic system with space group P21/c, a=1.327 5(3) nm, b=0.930 39(19) nm, c=0.948 44(19) nm, β=108.21(3)°, and V=1.112 8(4) nm3, Z=2, R=0.025 2, wR=0.066 1. Each copper(Ⅱ) atom is five-coordinated by three O atoms and one N atom from two different EDTA4- groups and one N atom from 3-PyOH ligand, forming a distorted square-pyramidal coordination geometry. Two adjacent copper(Ⅱ) atoms are bridged by the bis-tetradentate EDTA4- groups, constructing a two-dimensional layer structure along bc plane. The adjacent Cu…Cu distances are 0.502 5(3) and 0.611 3(3) nm. CCDC: 618806. 相似文献
64.
A novel binuclear copper complex of [Cu(C14H8O3)(C9H7N)(C2H5OH)]2 was synthesized and characterized by elemental analysis, IR, thermal analysis and X-ray single crystal diffraction. The title complex crystallizes in monoclinic system, space group
P21/c with a=1.381 7(3) nm, b=1.184 3(2) nm, c=1.332 5(3) nm, β=104.77(3)°. Each copper(II) atom is five-coordinated by three oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, one quinoline nitrogen atom and one ethanol oxygen atom, forming a distorted square-pyramidal coordination geometry. Two copper(II) atoms are linked by two 9-hydroxy-fluorene-9-carboxylate ligands into a dimmer structure with the Cu…Cu separation being 0.298 39(8) nm. The dinuclear motifs are further linked into a two-dimensional supramolecular layer via hydrogen bonds interactions. CCDC: 272850. 相似文献
65.
一维链状4-硝基-3-羧甲基苯异丙酸镉配位聚合物{[Cd(3-CNPP)(Py)3]·2H2O}n的合成、晶体结构及热稳定性研究 总被引:1,自引:1,他引:1
A novel one-dimensional coordination polymer, {[Cd(3-CNPP)(Py)3]·2H2O}n (3-CNPP2-=2-(3-carboxymethyl-4-nitrophenyl)propionate dianion, Py=pyridine) was synthesized and characterized by the element analysis, IR, TG and single crystal X-ray diffraction. The title complex crystallizes in monoclinic system with space group P21/ n, a=0.974 81(19) nm, b=1.992 3(4) nm, c=1.459 8(3) nm, β=95.92(3)°, and V=2.820 0(10) nm3 Z=4, R=0.037 3, wR=0.083 8. Each cadmium(Ⅱ) atom is seven-coordinated by four oxygen atoms from two different 3-CNPP2- groups and three nitrogen atoms from three pyridine ligands, forming a distorted pentagonal bipyramindal coordination geometry. The cadmium(Ⅱ) atoms are bridged by the tetradentate 3-CNPP2- groups, constructing a one-dimensional zigzag chain structure along c axis. The adjacent distance of Cd…Cd atoms is 0.979 6 nm. The two-dimensional hydrogen-bonding supramolecular network was formed via the hydrogen bond interactions. CCDC: 254257. 相似文献
66.
一维链状的3-羧基苯氧乙酸铜配位聚合物[Cu(3-cpoa)(phen)(H2O)]n的合成与晶体结构 总被引:2,自引:0,他引:2
A novel coordination polymer [Cu(3-cpoa)(phen)(H2O)]n(3-cpoa2-=3-carboxylphenoxyacetate, phen=1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Crystallographic facts are as follows: monoclinic crystal system, space group P21/n, a=0.688 96(14) nm, b=1.652 3(3) nm, c=1.651 1(3) nm, β=95.20(3)°, V=1.871 9(6) nm3, Z=4, Dc=1.618 g·cm-3, F(000)=932, μ=1.211 mm-1,R=0.048 2 and wR=0.062 2. The copper atom exhibits a distorted square pyramidal coordination geometry, involving two oxygen atoms of different 3-cpoa2- ligands, two nitrogen atoms of 1,10-phen ligand and one coordinated water molecule. The copper atoms are bridged by 3-cpoa2- ligand, forming a one-dimensional chain along c axis. The distance of adjacent Cu…Cu is 0.916 6(4) nm. A three-dimensional network structure is constructed by the intermolecular hydrogen bond and π-stacking interactions. CCDC: 219724. 相似文献
67.
应用(EI)MS/MS法研究了吡啶并苯并蒽酮以及苯并苯并蒽酮类异构体的裂解方式及其与结构之间的相关性,探讨了不同异构体中由M^i+产生的[M-H]^+、[M-HCN]^+、[M-COH]^+、[M-CO]^i+、[M-(CO+2H)]^i+以及[M-(CO+HCN)]^i+(i=1,2)等1价及2价离子在MS/MS-CID谱上的强度差异和裂解方式,发现是否含有氮原子以及氮原子和苯环位置的差异,是支 相似文献
68.
The novel coordination polymer {[Cd(p-CMSP)(Him)(H2O)]·3H2O}n (
p-CMSP2-=p-(carboxymethoxy)phenylthioacetate, Him=imidazole) was synthesized by the reaction of
Cd(NO3)2, imidazole and p-(carboxymethoxy)phenylthioacetic acid in an aqueous solution, and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The crystal structure is of monoclinic, space group
P21/c with a=1.144 0(2) nm, b=1.876 7(4) nm, c=0.877 89(18) nm, β=106.31(3)° and V=1.808 9(7)
nm3, Z=4, R=0.023 2, wR=0.051 4. Each Cd(II) atom displays a distorted octahedral coordination geometry, defined by three carboxyl O atoms from different
p-CMSP2- ligands, one S atom from thioether, one N atom from imidazole and one water molecule. Adjacent Cd(II) ions are bridged by
p-CMSP2- groups, resulting in a 2D layer structure. The adjacent Cd…Cd distances are 0.492 7 nm and 1.144 0 nm. Furthermore, such layers are linked through hydrogen bonds to form supramolecular network. CCDC: 269474. 相似文献
69.
一维螺旋链状配位聚合物[Cu(p-BDOA)(2,2′-bipy)·H2O]n的合成与表征(英) 总被引:5,自引:0,他引:5
A new copper(Ⅱ) coordination polymer, [Cu(p-BDOA)(2,2′-bipy)·H2O]n ( p-BDOA2-=benzene-1,4-dioxyacetate dianion; 2,2′-bipy=2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The Crystal crystallizes in orthorhombic system, the space group is P212121, with the unit cell parameters a=0.698 4(1) nm, b=1.559 7(3) nm, c=1.750 6(4) nm and V=1.906 8(7) nm3, Mr=461.91, Z=4, R=0.057 5, wR=0.078 3. Each copper(Ⅱ) atom is six-coordinated and displays a distorted square pyramidal geometry with a one-capped base by one very long semicoordinate Cu-O(carboxylate) bond. Adjacent Cu(Ⅱ) ions are bridged by carboxylate groups, resulting in a one-dimensional helical chain. The adjacent Cu…Cu distance within the polymeric chain is 1.348 4 nm. Furthermore, such chains are linked through hydrogen bonds and π-π stacking interactions to form supramolecular network. CCDC: 219234. 相似文献
70.
为实现嵌入式系统对LXI仪器的远程控制,采用DSP芯片扩展DP83848C以太网接口芯片的硬件方案和基于简化TCP/IP协议及RPC协议支持的软件方案,在分析TCP连接过程、RPC调用流程和VXI-11协议工作过程的基础上,设计实现了支持VXI-11协议的嵌入式硬件平台和控制软件;以R&S SMB100A微波信号源为被控对象的实验测试及数据分析结果表明,文中的硬件平台和控制软件可以根据协议工作时序正确发送控制数据包,LXI仪器可以正确响应嵌入式端的远程控制命令;文章提出的基于DSP和VXI-11协议的LXI仪器控制方案即可以用于实现分布式、低成本、灵活性较高的自动测试系统,也可以用于LXI仪器控制的桥接方案设计。 相似文献