排序方式: 共有60条查询结果,搜索用时 171 毫秒
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合成并表征了一种新的离子对化合物[4-NH2-Py][TCNQ](其中4-NH2-Py+是4-氨基吡啶阳离子,TCNQ-为7,7,8,8-四氰基对苯二醌二甲烷自由基阴离子)。在该离子对化合物晶体中,2个TCNQ-离子形成了面对面堆积的二聚体;阴离子中的氰基分别和阳离子上的氨基、吡啶质子化氮原子之间存在非常强的分子间氢键。通过氢键作用,相邻的TCNQ-二聚体被阳离子连成三维氢键网络。变温磁化率测量表明,在2~400 K温度范围内,该离子对化合物表现为抗磁性。在密度泛函理论框架下,用对称性破损方法计算了化合物晶体中π二聚体内以及通过氢键连接的相邻的TCNQ-离子之间的磁交换常数,发现π二聚体内存在非常强的反铁磁交换作用,与之相比,通过氢键连接的TCNQ-离子之间的磁交换作用可以忽略。π二聚体内强反铁磁交换作用(J/kB≈1805 K)导致了该化合物基本表现为抗磁性。 相似文献
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A novel cobalt complex,[Co2(bptc)(bix)1.5](1,H4bptc=3,3',4,4'-biphenyltetra-carboxylic acid,bix = 1,4-bis(imidazol-1-ylmethyl)benzene),has been hydrothermally prepared and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal is of triclinic system,space group P1 with a=10.770(7),b=12.245(8),c=13.514(9),α=102.829(8),β=107.734(8),γ=98.833(9)°,C37H27N6O8Co2,Mr=801.51,V=1607.5(18)3,Dc=1.656g/cm3,F(000)=818,μ=1.100mm-1,Z=2,the final R = 0.0694 and wR = 0.1543 for... 相似文献
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<正>Great interest has been focused on the rapidly expanding field of the construction of novel functional metal-organic frameworks(MOFs)owing to their variety of intriguing architectures and topologies and their potential applications in magnetism 相似文献
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A novel two-dimensional cadmium(Ⅱ) complex {[Cd(bpds)(bpp)2]·2H2O}n (1) with 4,4′-biphenyldisulfonic acid (H2bpds) and 1,3-bis(4-pyridyl)propane (bpp) has been synthesized by means of hydrothermal method and characterized by elemental analysis, IR spectrum, thermal analysis and single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a=0.900 96(12) nm, b=1.098 84(14) nm, c=1.125 71(15) nm, α=115.907(2)°, β= 92.307 (2)°, γ=105.383 (2)°, V=0.950 8(2) nm3, Dc=1.497 g·cm-3, Z=1, F(000)=440, Goof=1.046, R1=0.028 2, wR2= 0.074 9. Complex 1 shows a novel two-dimensional (2D) lamellar structure and further extended into a 3D supramolecular structure through O-H…O and C-H…O hydrogen bonding interactions. Luminescent studies show that complex 1 exhibits intense blue fluorescent emission. CCDC: 769593. 相似文献
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运用密度泛函理论,在B3LYP/6-31G(d)水平上对菲并咪唑(PI)及其8种2-取代芳基衍生物的结构进行了全优化,探讨了取代基对分子结构、电离势(I_P)、电子亲和势(E_A)、电荷转移、前线分子轨道能量和电子吸收光谱等方面的影响.采用含时的度泛函理论(TD-DFT)计算了各分子的气相及液相的电子吸收光谱,计算结果与实验值十分接近.并用GaussSum2.1程序模拟吸收光谱和态密度(DOS)图,结果表明,芳基4′-位上取代基对菲并咪唑(PI)和苯环的骨架结构没有很大的扰动,但它们重新调整了菲并咪唑环和苯环中原子电荷分布,前线分子轨道(LUMO)-HOMO)能隙降低,导致8种取代的化合物的吸收波长均发生了红移. 相似文献
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本文选取平面型配体2,2-联嘧啶(2,2-bipyrimidine,C8H6N4)和马来二睛基二硫烯二钠(Na2(mnt)),采用溶液合成法制备配合物[Cu(mnt)(C8H6N4)](1),并运用IR、XRD、X射线单晶衍射等方法进行了表征,还对其作了TG、EPR、磁性等研究。配合物1属于单斜晶系,空间群为P21/c,晶胞参数:a=0.71064(11)nm,b=1.6270(2)nm,c=1.27384(19)nm,β=98.926(2)°,V=1.4550(4)nm3;具有层状堆积的结构,层间距为0.3360 nm。磁性测试数据表明,配合物1具有顺磁性质。 相似文献
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各种均一配体的金属二硫纶 [1~ 4 ]、金属二亚胺 [5,6]以及二硫纶和二亚胺混合配体的金属配合物 [7,8] ,因其具有特殊的氧化还原性和光、电、磁功能 ,近 1 0多年来一直受到科学家们的高度重视。笔者的兴趣在于二氰基二硫纶 (mnt2 - )的过渡金属配合物 ,以及二氰基二硫纶和α,α′-二亚胺混合配体过渡金属配合物的合成、性质、结构和电子功能研究 [9~ 12 ] 。这些配合物不仅本身具有优异的气敏、光敏、催化等功能性 ,而且也是合成金属四氮杂卟啉的前驱物 [13~ 14 ]和自组装有序分子聚集体的功能元件之一[15] 。 最近 ,笔者合成和表征了… 相似文献
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A novel compound, (IBzQI)(TCNQ)2 2 (IBzQ1=1-(4-iodobenzyl)quinolinium and TCNQ = 7,7,8,8-tetracyanoquinodimethane) has been fabricated and X-ray single-crystal structurally analyzed. This compound crystallizes in the triclinic system, space group P1 with a = 8.3540(17), b = 13.284(3), c = 16.185(3) А, α= 82.12(3), β= 75.19(3), γ= 72.34°, V = 1651.2(6) А^3, Z= 2, C_40H_21IN_9, Mr = 754.56, Dc = 1.518 g/cm^3,μ= 1.015 mm^-1, S = 1.010, F(000) = 754, R = 0.0387 and wR = 0.0948. The structure analysis shows that the anions are stacked into column with tetrads, and there are two types of TCNQ entries (TCNQ-1 and TCNQ^0) in agreement with the IR spectra analysis of the compound. The temperature dependence of the magnetic susceptibility (2-300 K) for 2 exhibits spin gap of singlet-triplet feature, and the best fit gave △/kB = 1523.4 K. In order to understand both magnetic behavior and local charge distribution of [(TCNQ)2]-unit, the molecular orbital calculations and analysis based on extended Hückel method were performed, and the results support the analyses of both crystal structure and IR spectra. 相似文献