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A study is conducted which demonstrates that the films absorb a substantial amount of solvent (CHCL3) to which they are exposed. Organic solutes have high permeability in the films compared to the penetrants of similar size in gas permeation, as a result of this.

The realization of new spin-coatable, ultrathin cross-linked polymer blends exhibiting excellent insulating properties, large capacitances and enabling low-voltage organic thin-film transistor (OTFT) functions. The blending of appropriate commercially available polymers and organosilane cross-linking agents affords robust, smooth, adherent, pinhole-free, high-capacitance, low-leakage ultrathin gate dielectric materials.

Polarization-resolved surface second harmonic generation (SHG) experiments are performed on thin films of collagen I and IV molecules and conventional circular dichroism (CD) measurements. Collagen IV presents little CD and no SHG optical activity and collaged I exhibits large chiroptical effects involving both one-electron and excitonic coupling mechanisms.

The preparation of thin films simultaneously doped with two different luminescent molecules located in two different spatially separated regions is reported. Fluorescence and photoexcitation spectra of rhodamine 6G (R6G) in amorphous and structured thin films show that it is located inside the surfactant micelles of structured thin films.

Enantioselective surfactant-templated thin films that were fabricated through the sol-gel (SG) process are discussed. The resulting templated sol-gel matrix can be obtained in various forms of monoliths, ground powders or thin films.

Silica films with controlled thickness and refractive index is formed by the sequential absorption of a cationic polyelectrolyte and silica sols. The refractive indices of films are affected by relative humidity, reflecting the hydrophilicity of the silica surface.

The efficiency of the CO + NO reaction on size-selected Pd(sub n) clusters supported on MgO thin films strongly depends on the size. The efficiency of the reaction increases non-monotonically with cluster-size, revealing a local maximum for Pd15, whereas local minimum is observed for Pd20.

Electrochemiluminescence (ECL) can be obtained directly from the reaction of guanine bases in oligonucleotides in ultrathin films with the catalytic metallopolymer [Ru(bpy)(sub 2)-(PVP)(sub 10)(super 2+) without using a sacrificial reluctant. ECL and catalytic SWV peaks are sensitive to oligonucleotide hybridization and chemical DNA damage.

Ion mobility in thin organic films change dramatically near the liquid-vacuum interface. Nanometer films of glassy 3MP are much less viscous at the vacuum-interface than within the bulk of the film.

Self-assembly of KHCO3 is observed when glassy oligomerized films of poly[(aminopropyl)-siloxane)] containing K(super +) ions, denoted K(super +)/poly-APS, are exposed to CO2 and H2O. A multistep phenomenological model is proposed to account for the self-assembly.

The photophysical characteristics of light-harvesting dendrimer thin films are studied by photoluminescence near-field scanning optical microscopy (PL NSOM). It is found that the films exhibit pronounced nanoscopic domains and become more homogeneous.

The orientation of overcrowded aromatics in films with submonolayer coverage is investigated. It is found that the molecular order and orientation in thin films can be controlled by using the side chains in the molecules.

The effects of surface morphology on the anchoring and electrooptical dynamics of confined nanoscale liquid crystalline films are studied. It is found that the surface morphology induces a homeotropic alignment of the film confined in the cavity.

The adsorption of NO on MgO ulthratin films grown on a Mo(100) substrate results in the formation of N2O at low temperature (120 K). The isotope exchange experiments show that the reaction does not involve lattice oxygens.

A versatile two-step assembly method with organic and metal-organic chromophores cross-linked with palladium is used to understand the critical role of the molecular structure and reaction parameters on the nature of thin-film growth. The pivotal role of internal film morphology in the storage and usage of the palladium demonstrated the significance of both the internal film structure and deposition conditions on the assembly of molecular-based films.

Nanoscopic organic multilayers that serve as excellent gate dielectrics for thin film transistors using single-walled carbon nanotubes semiconductors are demonstrated. Results suggest the potential importance of new carbon-based electronic materials for high-performance logic circuit, displays, and other systems.

The first synthesis of calcium copper titanite, CaCu3Ti4O12 films on technologically important substrates unfolding the electronic dielectric functions of different nanostructured CaCu3Ti4O12 films by spectroscopic ellipsometry is reported. A robust link between the dielectric functions and the nanostructure of the CaCu3Ti4O12 films deposited under various conditions is developed.

A simple method to produce white light from sol-gel matrices, such as SiO2 and ZrO2, made with Ln(super 3+)-doped LaF3 nanoparticles co-doped with Yb(super 3+) ions is reported. Similar to SiO2 matrix, white light is observed with CIE coordinates of 0.37 and 0.31 when ZrO2 films are made with the Yb(super 3+)/Eu(super 3+), Yb(super 3+)/Er(super 3+), and Yb(super 3+)/Tm(super 3+) nanoparticles.

A quantum chemical calculation is conducted on the grafting of chain organosilane compounds on SiO2-hydroxylated solid surfaces. It is shown that a single molecule interacting with the surface lies flat to it, inhibiting further homogeneous film growth.

A high-optical-quality titania-based mesostructured film with cubic or 2D-hexagonal symmetry is fabricated. The results revealed that trifluoroacetate (TFA) coordinates the titanium center and forms a stable complex that is subsequently organized by the block copolymer species into ordered mesostructures.

The surface adsorption of three probe molecules-acetic acid, methanol, and water on a film composed of nanoscale anatase TiO2 particle is investigated using sum frequency generation (SFG) vibrational spectroscopy. The results revealed that acetic acid adsorption is nearly unaffected by the presence of water, while methanol/methoxy adsorption involves reversible hydroxylation/dehydroxylation when water is present.

A novel ABA-type triblock copolymer, where A and B correspond to azobenzene (Az) containing polymethacrylate and poly(ethylene oxide) (PEO), respectively is synthesized by atom transfer radical polymerization (ATRP). The findings indicate the active and quasi reversible photocontrol of 2D microphase separation in a monolayer formed by an ABA-type triblock copolymer with an azobenzene in the side chain.

Microscale organic synthesis is conducted by a newly developed capillary-based flow system, with the aid of microwave irradiation. The findings indicate that capillaries coated internally with thin films of Pd metal show tremendous rate accelerations and the thin films themselves are capable of catalyzing Suzuki-Miyaura reactions with no exogenous catalyst added.

A study of homogeneous rubbing followed by crystallization for poly(3-hexylthiophene) (P3HT) thin films is reported. The possibility to realize modifications on P3HT surfaces with spatial and geometrical control of the nanorubbing using the stylus of an atomic force microscope (AFM) is demonstrated.

The observation of finite regions of high conductivity in both n- and p-channel organic thin film transistors (OTFTs) based on vapor-deposited, polycrystalline organic semiconductor films using a solution-processed, solid polymer electrolyte gate dielectric is reported. Induced charge carrier densities well above 10(super 14) charges/cm(super 2) were achieved in polycrystalline n- and p-channel OTFTs gated by using a polymer electrolyte dielectric.

A model chemical system, which by virtue of the imposed microgeometry, autonomously detects a macromolecular phase transition occurring in a thin film and reports it in a visual form of color patterns is described. The results suggest that micronetwork reaction-diffusion systems are useful in rapid assessment absorptivities of other materials using different indicator pairs with different solvents.

The large-scale, long-range ordering of lamellae in thin films of poly(n-butyl acrylate) (PBA)-b-polyacrylonitrile (PAN) block copolymers was achieved by using a simple and versatile zone-casting technique. Ordered copolymer films were then successfully converted into ordered nanostructured carbons, which retained the oriented morphology of the PAN precursor.

A microscopic model of the interface between liquid water and a hydrophilic, solid surface, as obtained from ab initio molecular dynamics simulations, is presented. The results obtained show that in the liquid in contact with the clean substrate, molecular dissociation occurs in a manner similar to that observed in the gas phase.

The structural and electrical characterization of two new p-channel organic semiconductors from the class of hybrid acene-thiophene materials, 5,5'-bis(2-tetracenyl)-2,2'-bithiophene (1) and 5,5'-bis(2-anthracenyl)-2,2'-bithiophene (2) is reported. The thin-film structures are examined using wide-angle X-ray diffraction (XRD), grazing incidence X-ray diffraction (GIXD), and atomic force microscopy (AFM).

The effect of hydrophobic magnetic nanoparticles attracted to the electrode, by means of an external magnet, on the electrochemistry at redox monolayer-functionalized electrodes is reported. The results indicate that when the magnetic nanoparticles are attracted to the modified electrode surface, the diffusional electrochemical process is fully inhibited by the formation of a thin hydrophobic film on the electrode surface.

The study determined shear moduli for chemically polymerized and solvent cast regioregular poly-(3-hexylthiophene) films, using thickness shear mode acoustic wave resonators. It also explored the extent to which the principle of time-temperature superposition can be applied to a thin electroactive polymer film.

Hybrid mesostructured films prepared by cohydrolysis are synthesized along with self-assembly of an optimized methyltriethoxysilane- tetraethyl orthosilicate (MTES-TEOS) mixture with the purpose to reach a large order in the pore organization without 'point defects' are synthesized. It used these films to introduce a rigorous methodology, based on TEM and SAXS analysis followed by a computer simulation, to identify phases in these mesoporous films.

The preparation of a new class of copolymer films that consist of polymethylene (PM) with a low percentage of randomly distributed ethyl ester side groups, consistent with poly-(methylene-co-ethyl acetate) is reported. While ethyl diazoacetate (EDA) alone does not polymerize at gold surfaces but diazomethane (DM) does decompose on gold to grow PM films, the combined presence of EDA and DM results in the enhancements in film growth and promotes an alternative mechanism.

Two novel semiconductors based on thiophene-anthracene oligomers that show field-effect mobilities as high as 0.50 cm square/vs. and on/off ratios greater than 10 are reported. The high mobility of semiconductors can be achieved at relatively low substrate deposition temperatures.

An approach is developed for preparing noncollapsed and free-standing nanowire arrays on a conductive Au films and their potential use for inorganic-organic hybrid devices is demonstrated. This approach offers a potential technique platform for high-performance nanowire-based electrical-driven devices and might enable one bottom-up strategy for future technologies.

A method is presented to laminate polymeric semiconducting films using an elastomeric support made of poly(di-methylsiloxane) (PDMS). These techniques have enabled the study of interfacial interactions in polymeric thin film transistors.

The solid-state properties and field-effect transistor (FET) electrical behavior of several series of alpha, omega- and beta, beta'-fluorocarbon- and alkyl-substituted and unsubstituted oligothiophenes nTs (n=2-6) are compared. The thin films were grown by slow vacuum deposition over a range of substrate temperatures and/or by casting from solution are investigated with the help of X-ray diffraction and scanning electron microscopy.

The single-molecule (SM) spectroscopic methods are employed to study single site variations in the acidity properties of sol-gel-derived silicate films. The results are attributed to the buffering effects of surface silanols near pH 9 and enhanced pH sensitivity of the dye near pH7.

The highly conductive and transparent CSO thin films are grown on glass and single-crystal MgO(100) substrates at 400 degree Celsius by an MOCVD process. The XRD data reveal that all of these features as-deposited Sc-doped CdO (CSO) films are phase-pure and highly crystalline with features assignable are found to contract with the introduction of Sc(super 3+) in agreement with the full-potential linear augmented plane wave (FLAPW) calculations.

The preparation of anion-permselective cation-permselective and pH-switchable ultrathin polyelectrolyte multilayers with high stability and bipolar behavior through a photo-cross-linked structure is described. The bipolar ion-selective multilayer membranes are fabricated by alternating deposition of poly(acrylic acid)(PAA) and poly(allylamine hydrochloride)(PAH) modified with benzophenone groups.

Self assembled monolayers (SAMs) are thin organic films which forms spontaneously on solid surfaces and, useful as passivating layers and for the modification for the surface properties. A new patterning method using photocatalytic lithography of the alkylsiloxane SAMs and selective atomic layer deposition (ALD) of thin films is presented.

The preparation of reactive membranes and nanotemplates with nanoscopic cylindrical channels on the surface of various inorganic and polymeric substrates is described. The fabrication of nanostructured thin polymer films from supramolecular assembly is made for this purpose.

The characterization of the in situ evaporation induced self-assembly of a homogeneous silica/surfactant/solvent solution into a highly ordered surfactant-templated mesostructure is discussed. The nonvolatile silicic acid components replace water in acidic conditions with minimized siloxane condensation rate and maintain a fluid like state avoiding kinetic barriers to self-assembly.

The synthesis of donor-acceptor pi electron chromophore 5-{4-[2-(4,6-di-amino-[1,3,5]triazin-2-yl)-vinyl]-benzylidene}-pyrimidine-2,4,6-trione (DTPT) is discussed. ~16.8 A is the repeat distance between DTPT molecules in a H-bonded chain yielding a molecular tilt angle from the substrate normal of ~57 degree in the films after combining with the x-ray diffraction (XRD) data.

The synthesis, assembly, and thin film transistors of dihydrodiazapentacene is presented. It is found that these molecules are easier to prepare and have greater environmental stability than that of pentacene.

Thin films formed by melted powders of semiconductor alpha-quinquethiophene are studied. It is found that they exhibit a hierarchical self-affinity organization that spans scales from tens of nanometers to hundreds of micrometers.

The complete synthesis and characterization procedures to generate highly organized and oriented mesoporous titania thin films, using poly(ethylene oxide) (PEO)-based templates is reported. A critical discussion on all important chemical and processing parameters is provided which is essential for a rational design and the reproducible construction of mesoporous materials.

Constructing the film of poly(2,5-dioctyloxy-1,4-phenylene-alt-2,5-thienylene) is synthesized and behavior of this thin film at the air-water interface is studied by microscopy and reflection spectroscopy. The floating films are transferred by the Langmuir-Schafer (horizontal lifting) method onto various substrates.

A very simple solvent quenching approach to promote oriented poly(gamma-benzyl L-glutamate) PBLG aggregates by sequentially treating the films with good and bad solvents is demonstrated. It is observed that from ellipsometry thickness measurements has found that end-grafted PBLG chains are preferentially stretched away from surface when they are solvated in a good solvent such as chloroform, while they collapse in a bad solvent such as acetone.

A novel approach to fluorescence imaging involving a prefluorescent radical probe is developed and used with free radical photoinitiators in same manner as acid-sensitive dyes are used with photoacid generators. This system is used to study the photoinitiated radical processes in thin polymer films and in the preparation of functional fluorescent images.