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1.
分别以NMR技术、电喷雾质谱、紫外光谱和红外光谱等分析方法考察了瓜环[n](n=7, 8)与盐酸法舒地尔的相互作用. 实验结果显示, 盐酸法舒地尔与两种瓜环都形成了1∶1的包结配合物, 但其主客体配合物的作用模式随着瓜环空腔大小的不同而各不相同. 通过紫外吸收光谱法计算出瓜环[n](n=7, 8)与盐酸法舒地尔的包结常数分别为2 524 L/mol, 1 216 L/mol, 其范围在200 L/mol~10 000 L/mol之内,这说明瓜环对盐酸法舒地尔具有潜在的药物缓释作用.  相似文献   

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3.
该文测定了最近合成的[Co(H2O)4(NCS)2](18-C-6)的1H、13C、14N核磁共振谱,验证了其配合物的结构,并用红外光谱(IR)作了进一步的确定.  相似文献   

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High-spin states in 185pt have been reinvestigated via the reaction 173Yb(<'16>O, 4n) at a beam energy of 90 MeV. The previously known band based on the ν7/2<'->[503](f<,7/2>) Nilsson orbital has been extended to higher spin states. Properties of the ν7/2<'->[503](f<,7/2>) band have been discussed with an emphasis on the evolution of configuration while increasing the spin.  相似文献   

6.
结合紫外光电子能谱(UPS),X射线光电子能谱(XPS),原子力显微镜(AFM)和掠入射X射线衍射谱(GIXRD)等实验手段,系统研究了2,7-二辛基[1]苯并噻吩并[3,2-b]苯并噻吩在Cu(100)基底上的吸附、生长过程以及界面能级结构.发现第一层的分子平躺吸附于Cu(100)上形成稳定的物理吸附.随膜厚增加,分子取向转为直立于薄膜平面,生长模式转为岛状生长模式.分子取向的变化导致膜厚大于16A的薄膜的能级结构发生变化.直立取向的分子在表面形成由内向外的电偶极层,引起真空能级下降,功函数降低;而轨道电离的各向异性使得分子从平躺到直立时UPS得到的分子最高占据轨道(HOMO)峰型发生变化,且HOMO起始边向深结合能端移动整体上随着膜厚的增加,真空能级向下弯曲,HOMO下移,电离能则先减小后增大下移的能带结构利于电子从界面向表面的迁移以及空穴从表面向界面的迁移.  相似文献   

7.
本文通过对 [Fe3 O(Ala) 6(H2 O) 3 ](Cl O4) 7和 [Fe3 O(Gly) 6(H2 O) 3 ](NO3 ) 7· 3H2 O的 ESR谱的解析及变温磁化率的研究 ,得出它们的 ESR谱具有各向同性的特点 ;朗德因子分别为 2 .0 19和 1.997;两种配合物中铁离子间有反铁磁相互作用  相似文献   

8.
A series of chemical conversions of formyl derivatives of tetraphenylporphyrin is implemented, including the dimerization under the action of low-valence titanium, formation of a vinyl derivative by Wittig's reaction, and also the intramolecular cyclization with formation of isomeric verdins. By means of radical nitration, nitro derivatives of heterylporphyrins are obtained, which are exposed to a reaction of vicarious nucleophilic substitution of hydrogen with formation of 2,3-disubstituted derivatives. The previously unknown derivatives of the above-named porphyrins are obtained, and means for synthesis of well-known compounds are considerably improved. Reported at the VIIIth International Conference on Spectroscopy of Porphyrins and Their Analogs, Minsk, September 22–26, 1998. I. I. Mechnikov Odessa State University, 2, Dvoryanskaya Str., Odessa, 270026, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 512–515, July–August, 1999.  相似文献   

9.
Positron lifetime measurements were carried out on [Fe x Zn1–x (ptz)6](BF4)2 single crystals in the temperature range of 72–300 K. Complementary Doppler broadening spectra were also recorded at room temperature. The probability of the formation of o-Ps (lifetime 500–1400 ps) was between 10–30%. Both the spin density and the lattice parameters of the sample affected the lifetime of o-Ps through the ortho-para conversion and the pick-off annihilation, respectively. The positron annihilation technique proved to be a sensitive detector of the spin-crossover5T2 1A1 and of the concomitant phase transformation.  相似文献   

10.
张红  牛冬梅  吕路  谢海鹏  张宇河  刘鹏  黄寒  高永立 《物理学报》2016,65(4):47902-047902
利用紫外光电子能谱、X射线光电子能谱以及原子力显微镜系统研究了2,7-二辛基[1] 苯并噻吩并[3,2-b]苯并噻吩(C8-BTBT)生长在单晶Ni(100)上的能级结构随着薄膜厚度的演化以及薄膜的生长方式. 发现第一层C8-BTBT平躺生长且与Ni基底发生了化学吸附反应. 从第二层起分子直立生长且呈现岛状生长模式. 这种平躺至直立的分子取向转变, 导致薄膜的能级结构在第一层与第二层间发生阶梯式的变化, 真空能级与最高占据能级同步下降. 此后能带结构随着薄膜厚度的增加逐渐向下弯曲, 功函数随着膜厚的增加而减小. 同时还发现由于直立生长的C8-BTBT其层间电导率较差导致实验中的能级未能收敛. 实验结果提示对基于Ni和C8-BTBT的自旋器件需要插入缓冲层并尽可能减少C8-BTBT的层数.  相似文献   

11.
结合紫外光电子能谱(UPS)、X射线光电子能谱(XPS)和原子力显微镜(AFM)等实验手段系统研究了C8-BTBT沉积在层状Mo S2基底上的界面能级匹配、薄膜生长和分子取向。研究发现C8-BTBT分子竖直生长在Mo S2上,生长过程中界面的真空能级(VL)、最高占据态轨道(HOMO)和电离能(IP)都出现了非常规的弯曲现象。这种能级弯曲行为可归因于直立分子从界面相到体相的转变过程中,其分子倾斜角(θ)存在一定的渐变,这种渐变会在沿表面法线方向诱导出一系列的层间电偶极,最终导致能级的弯曲。同时θ的变化也会改变薄膜的表面极化强度,引起IP的逐渐减小。能级的弯曲在界面处形成类P-N结的效应会对C8-BTBT基电子器件的性能有很大的影响。  相似文献   

12.
运用原位FTIRS,UV/Vis和电化学方法研究了乙腈溶液中[Os Ⅵ(N)(NH3)4](CF3SO3)3在GC和Pt电极上的还原过程 .结果首次在Pt电极上检测到桥氮物种ν(N≡N)的红外谱峰,位于2 019和1 970 c m-1附近,分别指认为[Ⅲ,Ⅱ]和[Ⅱ,Ⅱ]混合价桥氮锇络合物.为进一步探讨桥氮偶联过程提供了新的谱学数据.  相似文献   

13.
利用能量为164—180MeV的35Cl束流,通过重离子核反应149Sm(35Cl,5n)研究了179Au的高自旋态能级结构.实验进行了γ射线的激发函数、X-γ和γ-γ-t符合测量.基于对实验测量结果的分析,首次建立了179Au的1/2[660](πi13/2)转动带.结合已有的实验数据,着重讨论了奇AAu核中1/2[660](πi13/2)转动带的带头激发能随中子数的变化  相似文献   

14.
In a first approximation the Debye-Waller factor (DWF) of molecular crystals is factorized into a molecular and a lattice part:f=f m f l. In the case of spincrossover compounds there is the unique possibility to measure differences of both parts in the two spin states by switching the spin states with the LIESST effect. Measurements of the DWF depending on temperature, -ray direction and spin state were performed with57Fe-Mössbauer spectroscopy on three single crystals (R¯3) of the spincrossover system [FexZn1–x(ptz)6](BF4)2 (ptz=1-propyltetrazole), a concentrated sample withx=1 and diluted ones withx=0.30 andx=0.005. The DWF decreases from 10 to 300 K by a factor of 100 and its anisotropyf /f increases from 1 to 5.4. The differences of the DWF in the low spin and the high spin state (after LIESST) for the diluted and the concentrated samples were measured at low temperatures ( 50 K). From these data both the Grüneisen constant of the lattice G=2.9 and the lowest IR active intramolecular frequency (45 cm–1 (HS), 58 cm–1 (LS)) have been determined. The contribution of the DWF from the acoustic modes of the lattice is calculated from the elastic constants of rhombohedral [Fe x Zn1–x (ptz)6](BF4)2. The contribution of the optical lattice vibrations is estimated. The influence of different DWF in the two spin states on the evaluation of the fraction of molecules in either spin state from Mössbauer area data is discussed.In partial fulfillment of his thesis.  相似文献   

15.
设计并合成了天然产物喹叨啉(Quindoline)的两个衍生物:苯并呋喃[3,2-b]喹啉和5-N-甲基苯并呋喃[3,2-b]喹啉,通过MS、1H NMR等手段确认其结构.运用紫外(可见光谱、荧光光谱和圆二色光谱研究了合成的衍生物与小牛胸腺DNA结合能力的强弱和结合方式.实验结果表明,5-N季铵化引入的正电荷能提高苯并...  相似文献   

16.
The structural, optical and ionic properties of thieno[3,4-b]pyrazine (TP) analogues have been studied using quantum chemical methods. The density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods were employed to optimise the ground- and excited-state geometries of TP analogues. Based on the ground- and excited-state geometries, the absorption and emission spectra have been calculated by using TD-DFT method with 6-311G(d,p) basis set. All the calculations were carried out in gas phase and in acetonitrile and chloroform medium. The solvent-phase calculations were performed using the polarisable continuum model (PCM). It has been observed that the effect of medium on the calculated absorption and emission spectra of these analogues is negligible. The calculated absorption and emission spectra are in good agreement with the available experimental results. This theoretical investigation shows that the fused-ring thieno[3,4-b]pyrazine analogues dibenzo[f,h]thieno[3,4-b]quinoxalines and thieno[3′,4′:5,6]pyrazino[2,3-f][1,10] phenanthroline have lower band gap than the thieno[3,4-b]pyrazine. Hence, these analogues can be used for the production of low band gap conjugated polymers.  相似文献   

17.
High-spin states in 179Au have been studied experimentally using the 149Sm(35Cl,5n) heavy-ion fusion-evaporation reaction at beam energies of 164—180MeV. Measurements of γ-ray excitation functions, X-γ coincidences and γ-γ-t coincidences were performed with 13 BGO(AC)HPGe and 3 LOAX detectors. Based on these measurements, a rotational band built on the 1/2[660](πi13/2) Nilsson state has been established for the first time, and this band has been assigned to 179Au according to the systematic of level structure in odd-A Au nuclei. Properties of the 1/2[660](πi13/2) band in odd-A Au nuclei are discussed with an emphasis on the band-head energy while changing the neutron number.  相似文献   

18.
Grain boundaries (GBs) relaxation is a promising and effective strategy to improving GB stability or stabilizing nanocrystalline metals. However, previous studies mainly focused on nanocrystalline pure metals and GB behaviors therein, without considering the role of foreign atoms such as impurity or alloying atoms in GB relaxation. In this work, the shear-strain induced structural relaxation of pure Cu Σ3 [110](112) symmetric tilt GBs (STGBs), and the effects of foreign elements (Fe and Ni) and temperature on the GB relaxation were investigated in detail by molecular dynamics method. The results show that shear strain can trigger the structural relaxation of pure, Fe- and Ni-containing Cu GBs by the emission of Shockley partial dislocations from Cu GBs. Both Fe and Ni have impediment effects on the shear-strain induced GB relaxation, though the content of Fe or Ni atom (0.00165 at.%) is quite low in the GB model. The temperature cannot trigger GB relaxation independently within the considered temperature range, but play a positive role in the shear-strain induced structural relaxations of pure, Fe- and Ni-containing Cu Σ3 [110](112) STGBs. Our work might gain new insights into the mechanically induced GB relaxation in nanocrystalline copper and could be beneficial for improving the stability of Cu GBs.  相似文献   

19.
《Ultrasonics sonochemistry》2014,21(4):1451-1460
A convenient one-pot protocol was developed for the synthesis of 1H-spiro[furo[3,4-b]pyridine-4,3′-indoline]-3-carbonitrile derivatives. This reaction was carried out through a three component condensation reaction of isatins, malononitrile, and anilinolactones in the presence of a catalytic amount of Et3N as an inexpensive and available basic catalyst in THF under ultrasound irradiation. The products were obtained in high yields and short reaction times. The main advantage of this synthetic method is that the obtained products in ultrasonic irradiations are different from classical heating.  相似文献   

20.
本文通过对[Fe 3O(Ala) 6(H 2O) 3](ClO 4) 7和[Fe 3O(Gly) 6(H 2O) 3](NO 3) 7·3H 2O的ESR谱的解析及变温磁化率的研究,得出它们的ESR谱具有各向同性的特点;朗德因子分别为2.019和1.997;两种配合物中铁离子间有反铁磁相互作用.  相似文献   

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