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1.
马世红  陈健 《光学学报》1996,16(11):600-1606
利用π-A等温线,小角X射线衍射和光学测量方法研究了一种取代富勒烯LB膜的结构特性。纯C60-Be分子以体相的形式存在于气-液界面上。氮冠分子作为隔层材料,与C60-Be分子相混合可以制备性能优良的LB膜。  相似文献   

2.
研究了两亲性卟啉5,10,15,20-四-(4-十六烷基吡啶基)卟啉溴化物在气-液界面上的成膜性能,制备了其LB膜。用扫描隧道显微镜和UV-Vis光谱,荧光光谱,小角X射线衍射等实验方法研究了LB膜的形貌和卟啉大环分子在LB膜中的排列、取向和分子间的相互作用。结果表明,制备的LB膜结构均匀,性能稳定,在LB膜内,脂肪链并不是直立的,卟啉分子大环几乎平躺在基片上。  相似文献   

3.
利用π-A等温线、小角X射线衍射(SAXD)和光学测量方法研究了一种取代富勒烯(C60-Be)LB膜的结构特性。纯C60-Be分子以体相(bulkphase)的形式存在于气-液界面上。氮冠(醚)(NC)分子作为隔层材料,与C60-Be分子相混合可以制备性能优良的LB膜。π-A、吸收和小角X光衍射测量表明:这种混合膜结构的改善是由于C60-Be分子镶嵌在NC分子的双脂链之间造成的。通过测量三次谐波产生(THG)可以推出C60-Be的三阶非线性系数χ(3)=2.1×10-11esu。  相似文献   

4.
用LB膜技术组装α—Fe2O3超微粒的研究   总被引:10,自引:0,他引:10  
用超声分散的方法将α-Fe2O3超微粒分子用于硬脂酸/正己烷/氯仿溶液中,用LB膜进行有序组装。结果显示:α-Fe2O3超微粒能均匀地分散在有机溶剂中,α-Fe2O3超微粒/硬脂酸单分子膜的成膜性能良好,复合膜中的α-Fe2O3超微粒有一定的有序性,α-Fe2O3超微粒硬脂酸复合LB膜具有层状结构。  相似文献   

5.
采用紫外可见吸收和二次谐波产生技术研究了“推-拉”型偶氮苯分子Langmuir-Blodgett(LB)膜的光谱和二阶非线性光学特性.4-硝基-4′-氨基偶氮苯(NAA)分子能制成很好的LB多层膜,在稀溶液中以单体的反式异构体形式存在,在膜中主要以J-聚集体的形式存在,LB膜的紫外可见吸收谱的吸收峰较之溶液的发生了52 nm的红移.NAALB膜的二阶非线性极化率χ(2)为19.59×10-8 esu,一阶超极化率β值较大,约为1.974×10-29 esu.其光学二阶非线性起源于电偶极子机制.  相似文献   

6.
通过对不同制膜条件下样品的π-A曲线及紫外-可见吸收光谱的测量,研究LB单分子层膜中半花菁衍生物(hemicyaninederivative简称HD)分子的聚集状态及其形成机制。纯半花菁衍生物单分子层膜中分子以H聚集体的形式存在导致吸收峰的兰移及有效分子二阶非线性极化率β(基频波长λ=1.064μm)的减小。实验表明聚集体的形成主要发生在压膜过程。提高压膜速度或降低压膜终极压力(拉膜压力)可显著减小分子的聚集程度,从而提高单分子层膜的光学非线性极化率。  相似文献   

7.
卟啉LB膜的分子取向,形貌和膜厚度研究   总被引:3,自引:0,他引:3  
研究了5,10,15,20-四(对-山嵛酸乙酯-α-氧代苯基)卟啉分子在气液罪肌的成膜性,制备了该化合物的多层LB膜,研究了分子中不同的基团在LB膜中的取向,观测了LB膜的形貌和厚度,利用偏振UV-Vis和偏振FT-IR谱测定了分子内卟啉环和脂链取代基的取向,结果表明卟啉面法线和脂缝线与载片线间的夹角分别为37°和27°,利用TEM观测了LB膜的形貌和厚度,结果表明LB膜表面均匀,单层厚度大约为2  相似文献   

8.
本文以LB膜技术研究了向列相液晶的取向机理。选择了四种不同金属的可溶性酞菁化合物MPc-R4作为取向材料,拉制成LB膜,诱导向列相正性液晶E-7。通过对菁酞LB膜的表征和液晶取向及电光性能的研究,认为液晶的取向是由分子间的相互作用力决定的。  相似文献   

9.
荧光法比吸光度法灵敏,更适用于超薄膜系如LB膜的表征。拉制了荧蒽和苯并[b]荧蒽镶嵌在硬脂酸基质中的LB膜,探讨了它们的稳态和时间分辨荧光性质。实验表明,两种分子以单体形式存在于LB膜中。  相似文献   

10.
双亲性席夫碱金属配合物LB膜的制备和结构特征   总被引:1,自引:0,他引:1  
合成了双亲性席夫碱配体与Zn^2+,Cd^2+的配合物,用元素分析,红外光谱和紫外光谱对配合物进行了鉴定,以L-B技术得到了层状有序多层膜。LB膜的紫外可见吸收光谱表明膜中分子形成了H-聚集体,且具有特定取向,该膜在紫外光的照射下,膜内配体分子发生的烯醇-醌式结构转变能够提高分子的非线性极化率,该结果有利于这类配合物薄膜材料非线性光学性质研究。  相似文献   

11.
Ultraviolet-visible (UV-Vis), infrared transmission, and reflection absorption(RA) spectra have been measured for one-and multi-monolayer Langmuir-Blodgett(LB) films of C16H3330Naph(1,5)OH at various temperature to investigate dependencies of the aggregation and phase transitions on the number of monolayers. The UV-vis spectra of the LB films have revealed that the C16H33ONaph(1,5)OH forms aggregates in the LB film. From the temperature dependence of UV-vis absorption spectra, it is clear that the aggregate is gradual converted to monomer upto 80 °C. A comparison of the infrared transmission and RA spectra reveals that the hydrocarbon chains are tilted considerably in the LB film. As for the naphthalene ring part, the result suggest that the ring plane is oriented approximately perpendicular to the substrate surface. The Temperature dependence of infrared transmission spectra have been measured for 1-, 3-, and 11-monolayer LB films to investigate dependence of phase transitions on the number of monolayers. These observations show that the one-monolayer LB films does not have a clear order-disorder transition, while the three-and eleven-monolayer films have a phase transition near 60 °C. Therefore, it seems that the title angles of both the alkyl chain and chromophore part change largely concomitantly with the conversion from the aggregate to the monolayer.  相似文献   

12.
Fourier transform infrared (FTIR) transmission, polarized transmission, reflection absorption (RA) and Attenuated total reflection (ATR) spectroscopy were employed to investigate the molecular orientation and molecular recognition to the complementary base at the air / water interface of a novel nucleolipid amphiphile, octadecanoyl ester of 1-(2-carboxyethyl) thymine. It has been found that the molecules are biaxially oriented and the hydrocarbon chain titled considerably from the substrate normal as well as the chromophoric part in the LB film Molecular recognition through complementary bases pairing takes place at the air / water interface between the thymine moiety in the head group of the amphiphile and adenosine in the subphase, the hydrogen involved in the host-guest interactions has been detected by using FTIR-ATR technique. FTIR transmission spectra measured at elevated temperatures revealed that the order-disorder transition of the LB film which contains the complementary base occurs at lower temperature. To our best knowledge, investigation of the order-disorder transitions in nucleolipid amphiphile LB films and comparative studies of the order-disorder transitions between nucleolipid amphiphile LB film that contains and does not contain the complementary bases have been virtually nonexistent, so far.  相似文献   

13.
光学非线性LB膜的时间稳定性与光致漂白效应的关系   总被引:1,自引:0,他引:1  
马世红  姚文华 《光学学报》1998,18(5):27-532
用光学二次谐波产生(SHG),拉曼散射和紫外-可见吸收光谱等方法研究了偶氮,苯腙及半花菁三种有机染料Z型Langmuir-Blodgett(LB)多层膜的时间稳定性问题,发现:随着放置时间的推延,其中LB膜的二次谐波产生信号强度下降,然后逐渐达到稳定;在高压汞灯光照射下,粉末样品中N=N(偶氮),C=N(苯腙),C=C(半花菁)键伸缩振动所对应的拉曼峰强度以及这三类染样在LB膜样品中对所应的生色团  相似文献   

14.
The Fourier transform infrared transmission (FTIR-T) and attenuated total reflection (ATR) spectra of the 5-(dodecyloxy)-1-((6-(trimethylammonio)hexyl)oxy)naphthalene — sodium dextran sulfate composite LB films deposited under the surface pressure of 30 mN/m have been recorded and spectral assignments made. By means of polarization techniques and with the application of the uniaxial and biaxial orientation models, the orientation characteristics of the long hydrocarbon chains and the = C-O linkage in the LB films have been investigated, giving rise to the detailed information of the arrangement of molecular fragments in the 1-SDS composite LB films.  相似文献   

15.
温度对稀土夹心双萘酞菁LB膜光学性质的影响   总被引:3,自引:0,他引:3       下载免费PDF全文
 采用线性吸收谱和二次谐波产生技术研究了温度对具有中心对称结构的稀土夹心双萘酞菁化合物LB膜光学特性及其LB膜结构的影响。研究发现,加热可以使其LB膜的结构及分子间的相互作用发生变化,并形成J聚集体,从而使得吸收峰发生红移。稀土夹心双萘酞菁化合物约在40 ℃时其二次谐波信号有一个极小值,约在65 ℃时该化合物发生相变,使得二次谐波信号产生极大值,二次谐波信号最小时温度可高达180 ℃,说明该化合物的化学结构较为稳定。  相似文献   

16.
虽然用红外光谱显微探针方法研究岩心中碳质物已有很多工作,但是通常对诸如岩心等样品物性的光谱学微探针实验研究多是局限于对经过复杂处理分离出的微小样品或样品中个别位点所得的结果,缺乏对复杂样品各组分(或基团)的空间分布及其相互关系的研究。近年来新发展起来的光谱成像分析系统将光谱技术与成像技术有机地结合起来融为一体,可在光谱和空间两个方面对目标样品进行分析和识别并已得到广泛应用,但是用红外显微成像光谱研究岩心的工作则少有报道。文章报道了应用透射和衰减全反射(ATR)两种方式对含油岩心进行了显微红外光谱成像(Mapping)的研究。从灵敏度、信噪比、光谱分辨率和空间分辨率以及工作效率等方面对两种方式所得实验结果进行了比较和评估。  相似文献   

17.
Infrared transmission, Reflectance-Absorption (RA) and Ultra-Violet (UV) spectra were measured for mono-and multi-layers Langmuir-Blodgett (LB) films of 4-[4′-(4″-decyIoxy phenylazo)naphthloxy] butyl trimethylammonium bromide formed with SDS to study the molecular orientation and aggregation. The results indicate that the compound do not aggregate in the LB films, and the alkyl tail is nearly perpendicular to the substrate surface and the chromorphore part adopts trans-zigzag conformation. These results also suggest that the molecular orientation and aggregation are not depend upon the number of monolayers The comparison of infrared transmission and RA spectra indicates that the hydrocarbon chain is nearly perpendicular to the substrate surface, but the two rings in the chromophore part are tilted considerably from the surface normal.  相似文献   

18.
Two different ways to form monolayers and LB films (surface film and subphase film) of the complex have been used, where a novel amphiphile containing Schiff base as a headgroup was used as a ligand. the monolayer behavior at the air/water interface was characterized by π-A isotherms and two-dimensional molecular orientation of alkyl chains in LB films and thermal stability were measured by polarized and variable temperature FTIR transmission spectra, indicating that the LB film of the novel amphiphile and its copper(II) complex are very stable as well as stearic acid. Because incorporating the metal ion into the monolayer makes it more condensed, thermal stability of the LB film was enhanced. as can be compared from their structure and properties, subphase films are superior to surface films.  相似文献   

19.
采用原子层沉积技术(ALD),以二乙基锌和水为前驱体,在衬底温度分别为110和190 ℃的条件下制备了致密的氧化锌纳米薄膜。采用X射线光电子能谱,荧光光谱和椭偏仪等表征手段对薄膜的成分和光学性质进行了研究。结果表明,随着沉积温度的增加,氧化锌薄膜内—OH含量降低,说明氧化锌薄膜生长过程中的化学反应更加完全;另外,沉积温度增加后,薄膜在365 nm处的激子发射峰出现了明显的增强,同时可见光区的荧光发射峰消失,表明薄膜内的缺陷态减少。随着成膜质量的提高,氧化锌薄膜的电子迁移率从25提高至32 cm2·(V·S)-1。椭偏测量的拟合结果表明,在375~800 nm的波长范围内,氧化锌薄膜的折射率逐渐从2.33降至1.9,呈现出明显的色散现象;另外,不同温度下制备的氧化锌薄膜光学带隙均为3.27 eV左右,这说明沉积温度对薄膜的带隙没有明显影响。  相似文献   

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