4-(6-羟基己氧基)联苯-4''''-甲酸-L-2甲基丁醇酯的合成及其液晶性的研究

运用示差扫描量热仪、偏光显微镜、X射线衍射仪和计算机模拟分子链处于能量最低、最优构象时的分子长度等手段，对新合成的4-（6-羟基己氧基）联苯-4’-甲酸-L-2甲基丁醇酯进行表征。结果表明：该液晶化合物为近晶A相。合成总收率为47．3％（相对于4-羟基-4’-氰基联苯）。     

新型含氟偶氮苯类液晶的合成和相变研究

设计并合成了一类新型的4′-（4″－n－烷氧基亚苯基乙炔基）4－n-乙氧基偶氮苯及其两个系列的氟代化合物,它们的相变行为通过差示扫描量热法和偏光显微镜进行了测试及观察,发现它们均是液晶化合物,都呈现向列相和近晶相,并且发现该类化合物的相变行为与氟原取代的数目与位置有着密切的关系。相比较不含氟的同类化合物,氟原子的引入降低了化合物的熔点和清亮点,如果两个氟原子对称分布在液晶分子长轴向的两侧有利于向列相的稳定性,相反分布于分子长轴一侧的两个氟原子有利于近晶相的稳定性／。     

取代苯基硫脲在Au表面自组装单分子膜的AFM观察

采用自组装（ＳＡ）技术制备了对甲苯基硫脲、对氯苯基脲和２，４，６－三溴苯基硫脲Ａｕ表面的自装单分子膜（ＳＡＭｓ）。在Ａｕ－溶液界面，硫脲Ｓ原子与Ａｕ－Ｓ键诱导吸附分子形成取向在序排列的单分子膜。用原子力显微镜（ＡＦＭ）对单分子膜进行了直接观察，ＡＦＭ所获得的结构信息与椭圆偏振测量、接触角测量和Ｘ－射线光电子能谱（ＸＰＳ）分析结果一致。     

激光化学气相沉积法制备铜膜的性能与形态分析

本文对以二（乙酸丙酮根）合铜（Ⅱ）和二（三甲基乙酰三氟代丙酮根）合铜（Ⅱ）为母体的化合物，用１０．６μｍ和２８０ｎｍ激光气相沉积法生成铜膜的形态及性能采用探针轮廓仪、扫描电子显微镜和四探针法进行了分析，观察到紫外激光生成铜膜中具有环状周期性图案的现象。     

激光化学气相沉积法制备铜膜的性能与形态分析

本文对以二（乙酰丙酮根）合铜（Ⅱ）和二（三甲基乙酰三氟代丙酮根）合铜（Ⅱ）为母体的化合物，用１０．６μｍ和２８０ｎｍ激光气相沉积法生成铜膜的形态及性能采用探针轮廓仪，扫描电子显微镜和四探针法进行了分析，观察到紫外激光生成铜膜中具有环状周期性图案的现象。     

4-(6-羟基己氧基)联苯-4′-甲酸-L-2甲基丁醇酯的合成及其液晶性的研究

运用示差扫描量热仪、偏光显微镜、X射线衍射仪和计算机模拟分子链处于能量最低、最优构象时的分子长度等手段,对新合成的4-(6-羟基己氧基)联苯-4′-甲酸-L-2甲基丁醇酯进行表征。结果表明:该液晶化合物为近晶A相。合成总收率为47.3%(相对于4-羟基-4′-氰基联苯)。     

分子器件

分子器件的主要研究内容包括：分子导线、分子开关、分子整流器、分子存储器、分子电路和分子计算机等。相关实验技术为：LB膜、自组装、有机分子束外延生长和扫描隧道显微镜等。     

纳米结构可重入STM/SEM超高真空多功能系统的研制

扫描隧道显微镜（ＳＴＭ）分辨率极高,是微观研究的重要仪器;但由于其视场小,样品易受污染等原因,在某些研究工作听应用受到了限制,扫描电子显微镜（ＳＥＭ）的最低放大倍数在十倍左右,视场可达２０ｍｍ＾２－３０ｍｍ＾２,可以引导扫描隧道显微镜进入试样预期的区域;另外超高真空的扫描电的样品室可以为扫描隧道显微镜提供清洁的工作环境,减少样品的污染。超高真空扫描电与扫描隧道显微镜的结合,可以弥补扫描隧道显微镜的     

海洋红藻R—藻胆蛋白的扫描隧道显微镜研究

Ｒ－藻红蛋白（Ｒ－ＰＥ）从海洋红藻多管藻中分离获得，然后用扫描隧道显微镜对其结构进行了研究。结果表明当Ｒ－ＰＥ在基底高定向石墨（ＨＯＰＧ）上吸附时，大部分蛋白分子聚集在一起，少数单个的蛋白分子分布于ＨＯＰＧ的表面。进一步缩小扫描范围，以可清楚地观察到Ｒ－ＰＥ分子为圆盘壮结构，但分子中央的孔洞的不象－Ｃ藻蓝蛋白那样清晰，这是由于λ－亚基位于分子的中央孔洞内。     

3-硝基-4-多氟烷氧基苯甲酸酯类液晶的合成和相变研究

设计并合成了一类新的3－硝基－4－多氟烷氧基苯甲酸4－[4-n－庚氧基－2，3-氟亚苯基乙炔基]苯酚酯液晶，并通过差示扫描量热法（DSC）和偏光显微镜对其相变行为进行了观察和测试。发现当氟碳链较短时，化合物呈现向列相和近晶A相，氟碳链增长后，化合物只呈现近晶A相。     

Au(111)表面自组装硫醇单分子膜的STM成像机理

本文利用基于密度泛函理论的算法模拟Au(111)表面紧密堆构型的烷烃硫醇自组装单分子层膜(SAMs)中单分子的扫描隧道显微镜(STM)图像，发现图像细节依赖于偏压和烃链链长，主要由受电子效应影响的形貌效应决定。同时进行了电子结构分析以研究硫醇SAMs的STM成像机制，还发现烷烃硫醇分子中的S原子在Au表面的吸附模式也明显地影响着STM图像细节。     

STM Lithography in an Organic Self‐Assembled Monolayer

We describe the suitability of ultra‐high vacuum scanning tunneling microscopy (UHV‐STM) based nanolithography by using highly ordered monomolecular organic films, called self‐assembled monolayers (SAMs), as ultrathin resists. Organothiol‐type SAMs such as hexadecanethiol (SH–(CH₂)₁₅–CH₃) and N‐biphenylthiol (SH–(C₆H₆)₂–NO₂) monolayers have been prepared by immersion on gold films and Au(111) single crystals. Organosilane‐type SAMs such as octadecyltrichlorosilane (SiCl₃–(CH₂)₁₇–CH₃) monolayers have been prepared on hydroxylated Si(100) surfaces as well as hydroxylated chromium film surfaces. Dense line patterns have been written by UHV‐STM in constant current mode for various tunneling parameters (gap voltage, tunneling current, scan speed, and orientation) and transferred into the underlying substrate by wet etch techniques. The etched structures have been analyzed by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM). Best resolution has been achieved without etch transfer for a 20 nm × 20 nm square written in hexadecanethiol/Au(111) with an edge definition of about 5 nm. Etch transfer of the STM nanopatterns in Au films resulted in 55 nm dense line patterns (15 nm deep) mainly broadened by the isotropic etch characteristic, while 35 nm wide and 30 nm deep dense line patterns written in octadecyltrichlorosilane/Si(100) and anisotropically etched into Si(100) could be achieved.     

Organic monolayers with uniform domain orientation and reduced antiphase boundaries – MBE of perylene on Au(110)

The growth of epitaxial monolayers of perylene on Au(1 1 0) was investigated by means of scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). The preparation was done by molecular beam epitaxy (MBE). The experimental setup allowed us to perform LEED or STM measurements during evaporation. The pattern of the adsorbed perylene molecules shows several dosage-induced structural transitions, leading to a final coincident monolayer structure with uniform domain orientation and a low density of antiphase boundaries. The underlying Au(1 1 0) interface exhibits several different reconstructions, depending on the perylene coverage.     

Growth and morphology of ultra-thin Ni films on Pd(1 0 0)

A series of Ni films with thickness from 0.2 monolayers (ML) to 12.5 ML were epitaxially grown on a Pd(1 0 0) substrate at room temperature. Growth and morphology were investigated by scanning tunneling microscopy (STM), reflection-high-energy-electron diffraction (RHEED) and Auger electron spectroscopy (AES). We found that the strain relief mechanism for the tetragonal distorted films is related with the appearance of 1 Å high-filaments.     

Direct observation of the stacked structure in substituted copper phthalocyanine LB films with STM

The in-plane molecular structures of octa-alkyl substituted copper phthalocyanine LB films deposited on graphite have been resolved with a scanning tunnelling microscope (STM). The face-to-face stacking of Pc macrocycles has been observed in the topographies of R₈PcCu monolayers. The stacking period was found to be 3.8–4 Å and the molecular rows were separated by 19 Å and 16 A for (C₆H₁₃)PcCu and (C₅H₁₁)PcCu respectively.     

Resistive switching in Rose Bengal and other Xanthene molecules is a molecular phenomenon

There has been a debate on the mechanism of resistive switching in Rose Bengal and other Xanthene class molecules. While some authors proposed that the switching was due to an oxide layer at the Rose Bengal/Aluminum interface, some inferred the switching as an extrinsic effect like filament formation. We show results from Rose Bengal and other Xanthene class molecules on doped Si. Conductance switching in such monolayers induced by Pt/Ir tip of a scanning tunneling microscope (STM) in a non-contact mode shows that resistive switching in these molecules, initially reported by us in 2003 (in thin films), is indeed a molecular phenomenon.     

STM·IPC-205B型扫描隧道显微镜的技术与应用

扫描隧道显微镜(STM)作为纳米科技中最为有效和重要的检测加工手段之一,其应用随着纳米科技热的兴起而日益引起人们的重视。本文简述了STM·IPC-205B型机的工作原理及应用,以具体实例的STM扫描图像说明STM具有广阔的应用前景。     

STM单分子剪裁术及其应用--纳米科技专家的手术刀

本文结合具体的实验,着重介绍了扫描隧道显微术（STM）诱导的单分子化学键断裂反应和成键反应（STM单分子剪裁术）的实验方法、剪裁机理和应用前景.STM单分子剪裁通过电压脉冲实现,化学键断裂和键合的能量来源于针尖和样品间发生非弹性隧穿的电子.STM单分子剪裁不仅可以对化学反应的路径进行控制,而且能控制和改变分子性质,实现某种物理效应,为单分子功能器件的制备提供一个重要的新方法.     

Hydrogen bond directed assembly of oligothiophene/fullerene superstructures on Au(1 1 1)

We previously reported that a branched quaterthiophene donor chromophore functionalized with a phthalhydrazide hydrogen bonding (H-bonding) unit (MeBQPH) gives twofold more efficient bulk heterojunction organic solar cells (with C₆₀ acceptors) compared to a nearly identical donor incapable of H-bonding (MeBQPME). Here, scanning tunneling microscopy (STM) studies confirm the formation of MeBQPH trimer rosettes on Au(1 1 1) through phthalhydrazide H-bonding interactions that are sufficiently strong to compete with adsorbate/substrate interactions. The MeBQPME comparator molecule void of hydrogen bonding functionality does not similarly assemble on the metal surface. Complementary density functional theory (DFT) calculations facilitate a structural understanding of the MeBQPH donor assemblies and their strong stabilization through formation of six hydrogen bonds. STM studies also reveal the templated growth of C₆₀ on ordered MeBQPH monolayers with C₆₀ molecules preferentially occupying the threefold interstitial sites of the MeBQPH monolayer. This work supports the idea that H-bonding interactions can be used to control the morphology of organic donor–acceptor blends to potentially create efficient and stable bulk heterojunction photovoltaic devices.     

基于隧道电流检测方式的原子力显微镜纳米检测系统设计

原子力显微镜（AFM）是当前进行材料表面微观形貌观察及分析的强有力工具之一。本文主要介绍一种隧道显微镜（STM）检测方式的原子力显微镜纳米检测系统（AFM.IPC-208B）,该AFM系统设计是在STM.IPC-205B系统设计的基础上,采用隧道电流工作方式,将STM与AFM功能组合兼容。文章详细阐述了AFM.IPC-208B系统的设计原理、镜体、扫描控制以及数据采集。新设计的AFM.IPC-208B系统仍具有0.1nm的分辨率,检测范围为0～2mm×2mm,系统操作简易,工作效率高,与原STM.IPC-205B系统兼容,工作性能稳定可靠。