A New Main Group Metal Coordination Polymer: Synthesis,Structure, and Dielectric Constant Property of [Na(C6H4N5)(H2O)2]n

The reaction of NaOH with 4‐(2H‐tetrazol‐5‐yl)pyridine affords the first tetrazole‐pyridine sodium coordination polymer with chain structure, [Na(C₆H₄N₅)(H₂O)₂]_n ( 1 ). The compound could be characterized by single‐crystal X‐ray diffraction analysis. The temperature dependence of dielectric permittivity remains unchanged almost within the measured temperature range of 80 K to 270 K at 1 <SC>MH</SC>z, and the frequency dependence of the permittivity showed rapidly drops from 31.5 to 4.3 within the measured frequency range of 200 to 1 MHz at room temperature.     

N—（β—羟乙基）乙二胺三乙酸锑的晶体结构

近年来锑配位化合物的晶体结构已有多篇报道,并探讨了这类化合物的结构在其抗肿瘤活性中的地位。本文报道N-(β-羟乙基)乙二胺三乙酸锑的晶体结构。 结果与讨论 N-(β-羟乙基)乙二胺三乙酸锑(C_(10)H_(15)O_7N_2Sb)为无色透明棱形片状晶体,20℃时密度ρο=1.82g/cm~3,实测值(理论值):Sb 30.2(30.7),C 30.0(30.3),H 3.9(3.8),N 6.8(7.1)。     

Radiative and nonradiative processes in LiGa5O8: Mn

The luminescence of LiGa₅O₈:Mn⁴⁺ was observed with measurements of decay times and intensities for different temperatures. The experimental results were analysed taking into account purely radiative, vibronic and radiationless transitions. It is shown that the nonradiative process involves 46 phonons, each with an energy of 304 cm⁻¹.     

Asymptotic behaviour of low density solutions to the generalized Becker-Döring equations

The asymptotic behaviour of solutions to the generalized Becker-D?ring equations is studied. It is proved that solutions converge strongly to a unique equilibrium if the initial density is sufficiently small. Received July 19, 1996     

Tween-20／BmimPF6／H2O微乳液的形成及结构

研究了30℃时Tween-20／BmimPF6／水三元体系的相行为，表明Tween-20／BmimPF6／水能形成单相微乳液。用电化学循环伏安法确定了这种新型离子液微乳液体系的微结构及结构转变。利用UV-Vis光谱探针技术，证明了微乳液液滴的形成，表明在W／IL微乳液中能够增溶金属盐，显示了这种新型的微乳液体系在材料制备和反应等领域的潜在应用。     

Bis{μ‐6,6′‐dimethoxy‐2,2′‐[propane‐1,2‐diylbis(iminomethylene)]diphenolato}bis[aquacopper(II)] dihydrate

In the title compound, [Cu₂(C₁₉H₂₄N₂O₄)₂(H₂O)₂]·2H₂O, the asymmetric unit consists of one half of the bis{μ‐6,6′‐dimethoxy‐2,2′‐[propane‐1,2‐diylbis(iminomethylene)]diphenolato}bis[aquacopper(II)] complex and two water molecules. Two Cu^II centres are bridged through a pair of phenolate groups, resulting in a complex with a centrosymmetric structure, with the centre of inversion at the middle of the Cu₂O₂ plane. The Cu atoms are in a slightly distorted square‐pyramidal coordination environment (τ = 0.07). The average equatorial Cu—O bond length and the axial Cu—O bond length are 1.928 (3) and 2.486 (3) Å, respectively. The Cu—O(water) bond length is 2.865 (4) Å, so the compound could be described as having a weakly coordinating water molecule at each Cu^II ion and two solvent water molecules per dimetallic unit. The Cu...Cu distance and Cu—O—Cu angle are 3.0901 (10) Å and 87.56 (10)°, respectively. The molecules are linked into a sheet by O—H...O and C—H...O hydrogen bonds parallel to the [001] plane.     

Raman studies in SmCFI* phases

The study of the Raman intensity of the 'breathing' mode of the benzene rings as a function of the temperature in smectic phases revealed strong anomalies of the intensities I_ZZ and I_YY in SmC_FI2* and SmC_FI1* phases, as well as an important shift of the principal optical direction with respect to other smectic phases. The analysis of these results provided evidence for significant structural changes at the SmC*-SmC_FI* and SmC_FI*-SmC_A* phase transitions, because the molecules can no longer be treated as cylindrical rods. No anomalies in the tilt angle were found. Experimental results suggest a relationship between the deviation of the optical axis and the particular structure of the SmC_FI* phases. The deviation of I_ZZ maxima as a function of the rotation angle Ψ and the behaviour evident under an electric field in SmC_FI* and SmC_A* phases clearly excludes the coexistence of SmC_A* and SmC* local domains in SmC_FI* phases.     

Lindleyanin and Bergapten‐8‐yl Sulfate from Pleurospermum lindleyanum

A novel cyclobutane‐type lignan with a six‐membered lactone ring, named lindleyanin ( 1 ), and a novel furocoumarinyl sulfate, named bergapten‐8‐yl sulfate ( 2 ), along with 7 known compounds were isolated from the whole plants of Pleurospermum lindleyanum. Their structures were established on the basis of spectral techniques and X‐ray crystallographic analysis of 2 .