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131.
Duo-Zhi Wang Jian-Rong Li Lei Li Xian-He Bu 《Journal of chemical crystallography》2008,38(12):931-936
Abstract Two metal complexes of 1H-triazo-4,5-f-1,10-phenanthroline (HL), CoL(SO4)0.5 · 4H2O (1) and MnL
2 · 2H2O (2) have been synthesized on hydrothermal conditions and characterized by elemental analysis, IR spectroscopy and single-crystal
X-ray diffraction analysis. Complex 1 was further assembled into a three-dimensional (3D) supramolecular network through the hydrogen-bonding interactions and
inter-molecular π···π stacking interaction, 2 further assembled into a two-dimensional (2D) layer structure. This result shows that hydrogen-bonding interactions and π···π
stacking interaction play important roles in the formation of coordination networks, especially in the aspect of linking the
multinuclear discrete subunits or low-dimensional entities into high-dimensional supramolecular frameworks.
Index abstract Two metal complexes of 1H-triazo-4,5-f-1,10-phenanthroline (HL), CoL(SO4)0.5 · 4H2O (1) and MnL2 · 2H2O (2) have been synthesized on hydrothermal conditions. Complex 1 was further assembled into a three-dimensional (3D) supramolecular network through the hydrogen-bonding interactions and
inter-molecular π···π stacking interaction, 2 further assembled into a two-dimensional (2D) layer structure.
相似文献
132.
The title compound 12-(2,4-dichlorophenyl)-7,8,9,10,11,12-hexahydrobenzo-[f]pyrimido[4,5-b]quinoline-9,11-dione DMF solvate 1(C24H20Cl2N4O3,Mr=483.34) was synthesized and crystallized.The crystal belongs to the monoclinic system,space group P21/n with a=6.4798(16),b=20.595(5),c=16.723(4),β=95.267(7)o,Z=4,V=2222.3(9)3,Dc=1.445 g/cm3,μ(MoKα)=0.328 mm-1,F(000)=1000,the final R=0.0530 and wR=0.1388 for 3484 observed reflections(I2σ(I)).X-ray analysis reveals that the central 1,4-dihydropyridine ring is slightly distorted,adopting a half-chair conformation,which is obviously different from the boat conformations of other similar compounds.In addition,the classical hydrogen bonds of N(2)-H(2A)…O(2) are presented in the crystals,and link the adjacent molecules to form dimmers.Atom O(3) in the DMF solvent forms two hydrogen bonds of O(3)…H(1H)-N(1) and O(3)…H(3H)-N(3) with a pyrimidoquinoline moiety,forming an interesting half-chair-like conformation.The hydrogen bonds link the molecules to form dimmers,while intermolecular π-π interaction connects the above-mentioned dimmers to yield a one-dimensional structure. 相似文献
133.
An ultrasonic-assisted solution-phase approach to tellurium bundles of nanowhiskers has been successfully established. It is a convenient and efficient process for the formation of Te nanowhiskers and their simultaneous assembly into tellurium bundles without using any templates. It was found that the transformation from Te powder to Te nanowhiskers involved the reversible disproportionation of tellurium. Sonication played a critical role for the formation of the Tellurium bundles of nanowhiskers. The bandgap of the Te nanowhiskers was calculated to be about 3.8 eV based on the UV-visible spectrum. The simplicity and rapidity of the procedure, and the newly discovered uniform morphology of the products made this synthesis promising and potential for related future applications. 相似文献
134.
用普通Korteweg-de Vries(KdV)方程作变换,构造(3 1)维KdV方程的解,获得了新的孤子解、Jaoobi椭圆函数解、三角函数解和Weierstrass椭圆函数解. 相似文献
135.
YANG Jian-Rong MAO Jie-Jian 《理论物理通讯》2008,50(10):809-813
A special coupled KdV equation is proved to be the Painleve property by the Kruskal's simplification of WTC method. In order to search new exact solutions of the coupled KdV equation, Hirota's bilinear direct method and the conjugate complex number method of exponential functions are applied to this system. As a result, new analytical eomplexiton and soliton solutions are obtained synchronously in a physical field. Then their structures, time evolution and interaction properties are further discussed graphically. 相似文献
136.
Cooperative Quantum Cutting of Nano-Crystalline BaF2:Tb^3+, Yb^3+ in Oxyfluoride Glass Ceramics
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We report on cooperative quantum cutting in Tb^3+- Yb^3+ codoped glass ceramics. Precipitation of BaF2 nanocrystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb^3+ ions under 485 nm excitation indicates cooperative energy transfer from Tb^3+ to Yb^3+. The quantum efficiency of this process reaches 145%. The realization of quantum cutting in glass ceramics may have promising applications in solar cells. 相似文献
137.
PbS-doped glasses are prepared. Absorption and luminescence spectra show that both the absorption and infrared emission can be tuned widely by thermal treatment conditions. Optical amplification at 1300 nm is observed, and amplified spontaneous emission (ASE) spectrum is also measured to confirm the optical gain from PbS quantum dots. 相似文献
138.
139.
以CF4,CH4和N2为源气体,采用射频等离子体增强化学气相沉积法,在不同射频功率下制备了含氮氟化类金刚石薄膜样品.原子力显微形貌显示,低功率下沉积样品表面致密均匀.拉曼及傅里叶变换红外光谱分析显示,随着射频功率的改变,薄膜的结构和组分也随之变化.紫外-可见光透射光谱证明薄膜具有紫外强吸收特性,通过计算得到其光学带隙在1.89—2.29 eV之间.结果表明,射频功率增加,薄膜内sp2C含量增加,或者说C=C交联相对浓度增加、F的相对浓度降低,导致薄膜内π-π*带边态密度增大,光学带隙减小.
关键词:
含氮氟化类金刚石薄膜
射频功率
光学带隙 相似文献
140.
在不同的氮分压r(r=N2/[N2+Ar])和射频功率P下,使用反应射频磁控溅射法,在玻璃基片上制备了氮化铜薄膜样品.用台阶仪测得了薄膜的厚度,用原子力显微镜、X射线衍射仪、紫外-可见光谱仪对薄膜的表面形貌、结构及光学性质进行了表征分析.结果表明,薄膜的沉积速率随P和r的增加而增大.薄膜表面致密均匀,晶粒尺寸为30nm左右.随着r的增加,薄膜颗粒增大,且薄膜由(111)晶面转向(100)晶面择优生长.薄膜的光学带隙Eg在1.47—1.82eV之间,随r的增加而增大.
关键词:
氮化铜薄膜
反应射频磁控溅射
晶体结构
光学带隙 相似文献