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The distance-dependent current-voltage (I-V) spectroscopy of the base-free naphthalo-cyanine (planar) and tin-naphthalocyanine (nonplanar) on a comparatively weak interacting substrate as highly oriented pyrolytic graphite (HOPG) is studied. The current-voltage curves show an unsymmetrical diode-like nature especially at large tip-sample distance in both cases.

Demonstrations regarding the Ware theoretical model that is suitable for the singlet energy transfer and for the triplet energy transfer are presented. The ns-ps two-color two-laser flash photolysis method could be applied to study bimolecular energy transfer process between short-lived species and triplet quenchers (Q).

A four-step procedure is reported for the transformation of diaryl ketones into polycyclic aromatic hydrocarbons and heterocycles that contain a newly formed, fused naphthalene ring system. The transition metal-catalyzed double ring closures of 1,1-diaryl-2,2-diethynylethylenes in the final step appear to work best for those compounds in which the distances between the atoms to be joined are less than about 3.35-3.40 angstrom.

Calculations were performed on fundamental and overtone CH-stretching vibrational band frequencies and intensities of neutral and cationic naphthalene and anthracene, which are the smallest of the polycyclic aromatic hydrocarbons. Simple and harmonic oscillator local mode model with local parameters obtained from scaled ab initio calculations and ab initio calculated dipole moment functions were used for these calculations.

Neutral photofragment spectroscopy is applied to record the vibrationally resolved electronic spectra of isolated protonated polycyclic aromatic hydrocarbons (PAHs)-naphthalene, anthracene and tetracene. The transitions observed for the neutral analogues in the visible region are attributed to the nature of the excited state which has a pronounced charge-transfer character for protonated linear PAHs with an even number of aromtic rings.

The side chains in the electron-rich dialkoxynapthalene (Dan) and electron-deficient 1,4,5,8-napthalenetetracarboxylic diimide (Ndi) derivatives were systematically altered and their 1:1 molar mixtures were explored to study the origin of the thermochromic behavior upon crystallizing from the mesophase. The levels of color change associated with crystallization were found to be controlled by the presence or absence of steric interactions due to side chain branching on the aromatic units.

A series of hybrid organic-inorganic [2]rotaxanes is prepared and characterized. The X-ray crystal structures of different [2]rotaxanes, a pseudorotaxane, and a two-station molecular shuttle has shown two distinct types of intercomponent hydrogen bond motifs between the ammonium groups of the organic thread and the fluoride groups of the inorganic ring. .

Time-resolved spectroscopy is used for comparing the photoinitiated charge separation (CS) and recombination (CR) in a series of donor-bridge-acceptor (D-B-A) molecules with cross-conjugated, linearly conjugated and saturated bridges. Molecular conductance calculations on the bridges have shown that cross-conjugation has resulted in quantum interference effects that have altered the through-bridge donor-acceptor electronic coupling as a function of charge injection energy.

The efficiency of any organic light-emitting diode (OLED) has decreased with prolonged operation and in fluorescent OLEDs containing the standard hole-transporting material NPB ([N,NE-diphenyl-N,NE-bis(1-naphthyl)-1,1' -biphenyl-4,4' -diamine], prolonged operation has resulted in chemical degradation of the NPB. The extent and location of chemical changes are consistent with the fact that chemical degradation of NPB is responsible for the loss of device efficiency and that the degradation is initiated by bond-breaking in excited-state NPB.

The introduction of a nitrogen atom at one of the acetylenic termini of 10-, 11-, 12-, and 13-membered benzannulated cyclic enediynes has resulted in the complete suppression of the conventional radical Bergman reaction in favor of a polar cycloaromatization. The latter reaction is catalyzed by acids and has proceeded by initial protonation of an ynamide fragment, where the resulting ketenimmonium cation has cyclized to produce naphthyl cation, which has reacted with nucleophiles or undergoes Friedel-Crafts addition to aromatic compounds.

The electronic properties of the molecular clips are elucidated by preparing the compound, the anti-configured isomer of orange-red molecular clip and the benzene-, naphthalene-, and anthracene-substituted quinones or the ehalf-clipsE. The configuration interaction in the excited states is considered to be a homoconjugation, indicating that the relevant charge transfer states are formed across an insulating aliphatic bridge.

The water-soluble, self-assembled, tetrahedral assembly [k.sub.12][Ga.sub.4][L.sub.6] (L = 1,5-biscatecholamidenaphthalene) has catalyzed the Nazarov cyclization of 1,3-pentadienols with very high levels of efficiency. The unprecedented rate increase is ascribed to both the stabilization of protonated reaction intermediates and the effect of constrictive binding on the bound guest.

The first oriented multicolored antiparallel redox gradients (OMARG-SHJs) with two-component redox gradients are described in both the electron- and hole-transporting pathways. The presence of both gradients is essential for achieving photoinduced charge separation over very long distances.

Electrical aging mechanism in blue emitting organic light-emitting devices (OLEDs) based on 9,10-bis(2-naphthyl)-2-t-butyl anthracene (TBADN) fluorescent emitter is examined by using delayed electroluminescence measurements. The results have shown that this species is efficient in dissipating excitation energy nonradiatively and is capable of quenching TBADN singlet excitons, thus contributing to the efficiency loss with electrical aging.

A new class of n-type semiconductors is described for organic thin film transistors (OTFTs), which is based on core-expanded naphthalene diimides fused with 2-(1,3-dithiol-2-ylidene)malonitrile groups. This class of n-type organic semiconductors has relatively low-lying LUMO levels and good film-formation ability, thus exhibiting good environmental stability even with prolonged exposure to ambient air.

The article explains the synthesis, as well as the properties of a new series of p-oligophenylene-linked donor-bridge-acceptor molecules. These molecules are shown to be widely used in numerous spin-selective charge transport pathways that are highly dependent on the damping coefficients.

Synchrotron radiation photoemission study was performed to gain insight into the energy level alignment at the interface between N, [N.sup.]-bis(naphthalene-1-y1)-N, [N.sup.t]-bis(phenyl) benzidine (NPB), a typical hole transport material, and Al which could be adjusted by precovering a thin [C.sub.60] layer on Al. The results showed that the barrier height for hole injection from Al to NPB could be lowered by as much as 0.98 eV, and the optimal thickness of the inserted [C.sub.60] layer was found to be 8-12 [Angstrom].

The detailed study report on the improved mechanism for device efficiency and the organic film morphology stability for organic light-emitting diodes (OLEDs) via incorporation of tungsten oxide (W[O.sub.3]) doped N,[N.sup.t] -di(naphthalen-1-yl)-N,[N.sup.t]-diphenyl-benzidine (NPB) hole injection layer is presented. The optically, electrically, and morphologically enhanced W[O.sub.3] doped NPD could find use as a promising hole injection layer for high efficiency and high stability OLEDs.

A threshold-voltage-corrected gate voltage is used to analyze the modification on the current-voltage characteristics of the n-channel organic thin film transistors fabricated on polyethylene naphthalate substrates. The improved performance of the device obtained with some of the self-assembled monolayer (SAM) treatments is attributed to both a better morphology of the semiconductor film, resulting in increased channel mobility, and to easier electron injection.

Mn-doped indium tin oxide (ITO) films are deposited on polyethylene naphthalate (PEN) substrates by using radio-frequency magnetron sputtering. Ferromagnetic hysteresis loops are observed at room temperature for the samples grown on PEN substrates and Mn-doped ITO films can be used as transparent ferromagnetic materials for flexible spintronic devices.

A detailed in situ study of the molecular orientation and electronic structure of 11,11,12,12-tetracyanonaphtho-2,6-quinodimethane (TNAP) vacuum-deposited on various metal substrates (Au, Ag, and Cu evaporated films) is presented. The results obtained demonstrated that doping not only changes the electronic structure but might also affect molecular orientation of TNAP.

Combination of dark injection space-charge-limited current (DI-SCLC) and trap-free SCLC measurements is used to demonstrate a quasi-Ohmic contact formed by the indium tin oxide (ITO)/buckminsterfullerene ([C.sub.60]) electrode with N,N'-bis(naphthalen-1-yl)-N, N'-bis(phenyl) benzidine (NPB). The Ohmic contact formed allows to estimate the NPB hole mobility through the use of both DI-SCLC and trap-free SCLC analysis.

The preparation of three rigid cubane-like photodimers, anti-head-to-head, anti-head-to-tail, and syn-head-to-tail from irradiation of 2-naphthalenecarbonitrile in solution with a light [lamdba] [greater than] 289 nm is reported. The easy manipulation and diverse substituted patterns of the photodimers could find application in cubane-like photodimers in the area of asymmetric catalysis and chiral assembly.

The three-component coupling reaction between phenylacetylene, carbon dioxide, and 3-bromo-1-phenyl-1-propyne was explored to develop a simple synthesis method for arylnaphthalene lignan lactones as valuable natural products. The level of regioselectivity for obtained products with promising anticancer and antiviral properties were enhanced by tuning the electronic properties.

Detailed study on a new terthiophene derivative substituted at the thienyl [beta] position with a naphthalenediimide functionalization is described. The findings from the UV-vis absorption, emission spectroscopic and electrochemical properties provide guidelines to control the electronic structure and also explore new strategies to obtain improved dyes.

The synthesis of variety of polyaromatic compounds having 1- and 2-naphthyl groups from the reactions of corresponding halides with tri(1- and 2-naphthyl)indium in good to excellent yields is reported. The study results for carbazoles having naphthyl groups show them to be promising host and hole transporting materials in organic electroluminescence due to their high thermal stability, electrochemical reversibility and wide band gap.

Several experimental and computational studies are conducted to examine the viscosity, as well as the ion conductivity in the [bmim][P[F.sub.6]]/naphthalene mixtures. The viscosity is shown to increase monotonically with the increasing ionic liquid (IL) mole fraction.

A study was conducted to measure the field-dependent hole mobility of 4,4',4'-tris(1-naphthylphenylamino)triphenylamine (1-NaphDATA) with three different methods on a set of hole-only samples with layer thicknesses d between 100 and 500 nm. The results revealed that the field dependence of the mobility depends on the measuring method.

The synthesis and characterization of naphthalenic-based sulfonated naphthalenic polyimides (SPI) membranes from the diamines is described. The membranes exhibit protonic conductivity similar to perfluorinated membranes such as Nafion.

The synergistic effect of a lifetime-extending light-emitting-layer (LEL) additive and improved electron injection and transport in organic light-emitting diodes (OLEDs) is described. The studies have shown that 4,7-diphenyl-1,10-phenanthroline (BPhen) in electron-injection and electron-transport layers is detrimental for the lifetime of the device.

The structure and the effects of the confinement of small water clusters between two benzene and two naphthalene molecules on the transport of protons are studied. The results prove that only a specific range of confinement helps in lowering the energy barriers of proton transfer.

The photochemical reactions in thin water films as present in aerosols and fogs are studied by analyzing the adsorption and photochemical transformations of gas-phase naphthalene using Suwannee River fulvic acid (SRFA) as surfactant. The thinner films show enhanced surface reaction at low concentrations of SRFA.

The mass spectroscopic studies of naphthalene dimer-argon clusters along with a rare tagging technique show the presence of a T-shaped naphthalene dimer chromophore.

The [super 13]C chemical shift tensors measured from two-dimensional (2D) FIREMAT on 4,7-di-t-butylacenaphthene and 4,7-di-t-butyl-acenaphthylene is described along with a series of calculations on both compounds. The experiments have revealed a break in symmetry caused by the crystal packing that has given rise to additional spectral lines beyond those that would predict on the basis of molecular symmetry in an isolated molecule.

The effect of different annealing ambients on the electrical and optical properties of indium tin oxide (ITO) on polyethylene napthalate (PEN) is analyzed. The results have shown that the different annealing ambients affect the electrical properties of ITO/PEN samples by changing the oxygen vacancy in the ITO layer and the conductivity of an ITO film is obtained by carrier concentration rather than mobility.

The electron transfer (ET) in four symmetrically substituted naphthalene-bridged bis-hydrazine radical cations is compared within the Marcus-Hush framework. The results show that ET rates estimated for four naphthalene bridged bis-hydrazine radical cations vary significantly and show no correlation with the distance between the charge-bearing units.