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We have studied the deposition of Zn metal onto a polished gold-coated quartz crystal with in situ tapping-mode atomic force microscopy (AFM), while simultaneously recording chronoamperometric and acoustic impedance quartz crystal microbalance (QCM) measurements. We are able to demonstrate good correlation between the three techniques. Modeling of the chronoamperometric dam recorded for the initial nucleation process of the same experiment suggests that nucleation initially occurred via a progressive mechanism. Crystallites of different sizes were clearly visible from the AFM images throughout the whole deposition time monitored, suggesting that sustained nucleation also occurs via a progressive mechanism. 10.1021/ac901329e

An optimization procedure is applied to the physically more rigorous solvation model, the generalized Born with surface area (GB/SA) together with the all-atom AMBER force field. There were no significant differences in performance among the 3 GB/SA studied and the differences are not very large and for certain individual loops are reversed.

The combination of in situ ellipsometry with atomic force microscopy (AFM) in the liquid study of adsorption of creatine phosphokinase (CPK) was presented. The thickness, the adsorbed amount, and the topography of the immobilized CPK layer onto silicon (Si) wafers were obtained under different pH conditions, the nature of interactions between CPK and Si wafers associated with the hydration forces control the degree of CPK unfolding upon adsorbing.

An investigation is presented of the nanotribological properties of C60 single crystal (111) and (100) surfaces around its orientational order-disorder phase transition temperature by atomic force microscopy and frictional force microscopy (AFM/FFM) in high vacuum. Results reveal that for both surfaces across the phase transition temperature, the friction force and the adhesive force between a C60 coated AFM tip and the C60 crystal surfaces exhibit discontinuous behavior.

A method to measure charge within a molecular circuit that shows negative differential resistance by conducting probe atomic force microscopy is presented. It is observed that the voltage region over which conduction was enhanced correlated strongly with the region over which the scanning probe tip experienced capacitive attraction to the surface.

The study created random parallel nanostuctures by scattering gold thin films deposited on glass slides. Atomic force microscope (AFM) images concluded that the width of the substructures within the scratches were of the order of a few hundred nanometers.

The electroformation of a Cu2S phase, obtained by sulfidization of a thin film of copper placed by the coating technique onto the gold surface of a gold/quartz crystal that is part of an electrochemical quartz crystal microbalance is studied. Atomic force microscopy revealed that the Cu2S phase electroformed on the gold/crystal quartz electrode is deposited as hemispherical particles on the terraces and in the cavities present in the gold film.

Atoms can be observed and determined for positions on nonconductive surfaces with the advent and progress of atomic force microscopy (AFM) technique. For the first time the array and orientation of the adsorbed molecules on zeolite surfaces could be determined.

The tip of an atomic force microscope has been used to manipulate multiwalled carbon nanotubes on a passivated silicon surface. Multiwalled carbon nanotuves were dissolved in methylene chloride using an ultrasonic bath and the solution was dissolved dispersed on a H-passivated Si(100) surface. The results showed that the interaction between the nanotubes and the substrate can stabilize highly strained nanotube configurations, with the resulting distortion inducing changes on the electronic structure and electron transport properties.

Scanning tunneling microscopy and atomic force microscopy were both proven to be effective as analytical tools in different chemical experiments. Both techniques provided highly accurate and reliable measurements. Recent advances in the field included formation of better calibration methods and probe tips. Moreover, materials which gave surface regions high-resolution properties have been developed, greatly increasing the imaging power of both techniques.

A new molecule to be adopted as a tip for scanning probe microscopies (SPM) that gives a smaller radius and has potential for chemical identification in submolecular resolution is presented. Reversible switching between the trans-and cis forms is successfully confirmed by NC-AFM measurements.

An important role is played by grain boundaries (GB) in the transport properties of field effect transistors based on polycrystalline organic semiconductor films. GB's trap and scalter mobile charge carriers are expected to increase the overall film resistance.

The study aims at an improved understanding of the mechanisms of protein resistance of poly ethylene glycol (PEG) layers, using the combcraft-copolymer poly(L-Iysine)-g-poly(ethylene glycol) (PLL-g-PEG), and concerns the effects of systematic variations in the surface properties, in particular PEG chain length and density, and surface charge. The combination of atomic force microscopy surface force measurements and protein adsorption experiment provides insights into the interfacial forces associated with various PEGylated surfaces and the mechanisms of protein resistance.

Atomic force microscopy (AFM) technique was employed for examining the formation of iono-platinic phases by cathodic modification of platinum surfaces. The modification begins at the interface solution platinum surface and involves the insertion of cations and salts into the platinum electrode.

Atomic force microscopy based technique-single molecule force spectroscopy was used for examining the single-chain nanomechanical properties of poly (N-vinyl-2-pyrrolidone) (PVPr) and povidone-iodine (PVPr-I2) under different solution conditions. The force-extension curve (force curve) of PVPr in water is deviated from that obtained in ethanol or tetrahydrofuran.

A study is conducted to give a survey of the classical works in mechanochemistry and put the key mechanochemical phenomena into perspective with the results from atomic force microscopy and quantum molecular dynamic simulations. The peculiar characteristics of mechanochemistry can be identified on the basis of the experimental and theoretical results.

Atomic force microscopy studies of the physical parameters determining the strength of lipid anchorage in bilayers as a function of the phase state of the lipid matrix are reported. Analysis of the data using both dynamic force spectroscopy and full microscopic models show that the anchorage strength is greater in gel-phase relative to fluid-phase lipids.

An interesting immobilization technique of liposomes on electron-beam exposed resist surfaces is found. The immobilized liposomes are visualized by the atomic force microscope and have shown well-organized three-dimensional physical structures, in which the liposomes maintain their shapes and sized similar to those of the original design in prepared solution.

Solution cast 2-(4-Biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) single crystals with different crystallographic axes perpendicular to the Au/S substrates in large area are achieved by controlling the rate of solvent evaporation in the presence and absence of external electrostatic field respectively.

An efficient implementation of the GB/SA approach with the OPLS-AA (all-atom) force field is described. Migration to the OPLS-AA model allows much broader application, and it also yields improved accuracy in predicting free energies of hydration.

The structural organizations of Lanmuir monolayers of the alpha-helical peptide alamethicin, which forms voltage-gated ion channels in lipid membranes, is studied y means of synchrotron X-ray diffraction, surface potential technique, surface pressure/area isotherms, and atomic force microscopy (AFM). The effects of hydrogen-bond promoters, pH, salt content of the aqueous sub phase, and lipid-peptide interactions were also analyzed.

The interfacial structures of a solution-cast variable acid film, before and after immersion in water were studied by X-ray scattering combined with atomic force microscopy. It is shown that the interfaces of the as-deposited film are self-affine.

Unrecognized strong correlation between the morphology of the PbO(sub 2) deposits and their electrocatalytic activity is discussed. An indicator of the catalytic activity of the corresponding films, leading to the observation of the correlation between deposit morphology and catalytic activity is mentioned.

During the sliding of an atomic force microscope (AFM) tip on the hydrophilic rough surface, water capillary bridges can form between the tip and the asperities of the surface. The total capillary force due to these bridges increases with the normal load following a 2/3 power law and an analytical relationship is derived to explain the interplay between humidity, velocity, and normal load in nanoscopic friction.

The spatial structure of the J-aggregates of meso-tetra (4-sulfonatophenyl) porphine (TPPS4) formed in aqueous solutions and coated on silicon substrates is analyzed in the light of atomic force microscopy (AFM). The study shows that TPPS4 equilibrium aggregates formed in aqueous solutions preserve a stable structure on the substrate and can be used for further optoelectronic applications.

The growth and structure of hybrid clay-based multilayers obtained by electrostatic self-assembly of poly(diallylpyrrolidinium bromide) and a synthetic hectorite (Laponite) is reported. By combining ellipsometry, atomic force microscopy (AFM), and specular grazing angle X-ray scattering measurements, a complete set of data, in both direct and reciprocal spaces, on the structure of {P/Laponite}(sub n) is obtained.

An atomic force microscopy (AFM) of the dependence of unbinding force on temperature at controlled loading rate is investigated. The thermodynamic model with additional insights, the bond stiffness, effective unbinding length, and the critical unbinding energy per biotin-avidin complex is estimated.

A scanning probe microscopic study was conducted, using atomic resolution scanning tunneling microscopy (STM), noncontact atomic force microscopy (NC-AFM), X-ray photoemission spectroscopy (XPS), low-energy electron diffraction (LEED), and formic acid adsorption experiments, to characterize the (001) surface of anatase TiO2. The result reveals that the formation of the anatase (001)-(1 x 4) reconstruction is governed by a mechanism of bulk-reduction, where interstitial Ti(super n+) species are produced and surface Ti(super 4+) is eliminated.

Atomic force microscopy is used to examine the structure of a nature eumelanin isolated from the ink sacs of cuttlefish (Sepia officinalis). Results show that the self-assembly of Sepia enumelanin is a hierarchical process with small units assembling into hundred-nanometer structures, which then aggregate to form the morphology of the macroscopic pigment.

A study was conducted to explore the unique structural patterns of a room temperature ionic liquid (IL) on a well-defined solid surface by employing atomically flat mica as the substrate to adsorb a prototype ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate, [Bmim][P[F.sub.6]]. Multilayer structures, including liquid and solid phases of [Bmim][P[F.sub.6]] were directly observed coexisting on mica substrates at room temperature by tapping mode atomic force microscopy (AFM) in air.

The contrasting method for atomic force microscopy (AFM) to substantially improve the resolution of a single molecule experiment with no changes of the conformation of adsorbed polymer molecules is presented. The innovation is considered important for the development of single molecule experiments with polymer chains.

High-resolution sensing of a wide range of materials is carried out by atomic force microscopy operated in noncontact mode (NC-FAM), regardless of their conductivity. The feasibility of the method in single-molecule analysis is presented for acetate and formate.