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The absorption coefficient [alpha]([omega]), the transverse dielectric function [epsilon]([omega]), the optical conductivity [sigma]([omega]) and the reflectance R([omega]) calculated for an emeraldine salt conducting polymer in its crystalline 3-dimensional (3D) polaronic structure is presented. Kohn-Sham density functional theory (DFT) electronic wave functions and energies are implemented in the expression of the macroscopic transverse dielectric function in the framework of the band theory without the electron-hole interaction.

A strategy is described for designing high-performance, ambipolar, acene-based field-effect transistor (FET) materials, which is based on the replacement of C-H moieties by nitrogen atoms in oligoacenes. The demonstration of high and balanced ambipolar FET properties from nitrogen-containing oligoacenes has provided new opportunities for designing high-performance ambipolar organic semiconductors.

Secondary ion mass spectroscopy and photoemission spectroscopy has shown that aliovalent ion substitution of Mg at the La site is not the main source of hole doping and the Fermi level has not shifted even in heavily doped LaCuOSe Mg. The studies have shown that planar defects composed of Cu and Se deficiencies are created in LaCuOSe, which are explained by the existence of a degenerate low-mobility layer and formation of complex Cu and Se vacancy defects with the help of generalized gradient approximation band calculations.

Self-threading polythiophene is described whose conjugated molecular wire is sheathed within its own cyclic side chains. The defect-free insulating layer has prevented electronic cross-communication between the adjacent polythiophene backbone in the solid film and the covalently linked cyclic side chains have extended the effective conjugation length of the interior polythiophene backbone.

The surface electron and hole availability is tuned by the adsorption of [Cl.sub.2] or [O.sub.2] to study the role of electrons and holes in the electronically excited oxidation of adsorbed CO on Ti[O.sub.2](110). The study results provide evidence for the electronically excited CO oxidation reaction which is caused by an electron-mediated process in contrast to [O.sub.2] desorption which is mediated by holes.

A study was conducted to examine the influence of three different fullerene derivatives on the charge generation and recombination dynamics of polymer/fullerene bulk heterojunction (BHJ) solar cell blends. The internal electric field in combination with polarization effects and the dynamic nature of polarons in the BHJ solar sell are the key features to overcome electron-hole interaction to form free extractable charges.

The application of the different thallium hyperfine clocks in determining the rate of hole transfer exhibited by the oxidized porphyrin dyads is discussed.

The article presents a new approach, which can be employed for the generation of new sites that can be used for trapping photogenerated holes on the surfaces of the rutile Ti[O.sub.2] nanoparticles. The trapping activity is shown to lead to a significant enhancement in the photocatalytic activity of the system.

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.

The patterning of a surface with more than one type of functionality in spatially resolved fashion is described. The two newly created surface functionalities can be used independently to locally deposit complementary materials such as electron- or hole-transporting molecules via self-assembly.

The hyperfine-clock strategy is applied to dyads of dihydroporphyrins (chlorins) and a de novo synthetic strategy is used to introduce a [super 13]C label at the 19-position of the chlorin macrocycle. The analysis of the chlorin and phorphyrin dyads has provided insights into the structural features that affect the hole/electron-transfer process.

A mechanistic study on a novel nanobelt structure of single-crystalline anatase Ti[O.sub.2] that overcomes the drawback of sphere-shaped nanoparticles and provides a new concept for rational design and development of high-performance photocatalysts is reported. The results provide insight into the photocatalysis efficiency of nanocrystals which could be significantly improved by tailoring the shape and the surface structure of nanocrystals.

The self-assembly of the nanofibers with built-in donor/acceptor heterojunction upon admission of MeOH, the enantiomerically pure form of chiral amphiphilic porphyrin-fullerene dyad in presence of C[H.sub.2][Cl.sub.2] is reported. The electron and hole mobilities under zero electric field estimated from time-of-flight profiles are comparable to those reported for top-class organic materials with a donor/acceptor heterojunction.

Host-guest complexation was employed to accomplish electrochemical implantation of a water-insoluble diazonium salt in aqueous media onto an electrode surface. The developed process could also be applied to construct a surface made of submicrometric holes in an organic semiconducting layer.

X-ray absorption near-edge structure spectroscopy is utilized as a probe to examine the hole states of phases of the homologous series of (Cu,Mo)-12s2, for which the member phases differ from each other by the number (s) of cation layers in the fluorite-structured (Ce,Y)-[[[O.sub.2]-(Ce,Y)].sub.s-1] block between the Cu[O.sub.2] planes. The [T.sub.c] value of superconductive copper oxides is found not to depend on the distance between two adjacent Cu[O.sub.2] planes as long as the hole-doping level and the immediate (crystal) chemical surroundings of the planes are kept the same.

A new method is described for preparing polyrotaxanes and it is applied to the synthesis of a polyrotaxane having a poly(phenylene ethylnylene) backbone by the Sonogashira copolymerization of a structurally defined rotaxane with a linker molecule. The time-resolved microwave conductivity has shown that hole mobility along the [pi]-conjugated polymer chain of the polyrotaxane thus formed is extremely high and comparable to that in amorphous silicon.

The article presents a comparison of the theoretical analyses and the calculations conducted to determine the size-dependence of carrier mobility and polarity as observed in graphene. The electron and hole mobility in such compounds is shown to highly vary with the width of the carbon ribbon.

Hole-transporting framework formed by surfactant-templated sol-gel polycondensation of an electroactive phenylenevinylene-based organosilane precursor is described. Electroactive organosilicas with mesopores and large surface areas have great potential applications for novel photovoltaic and photocatalytic systems.

The synthesis of poly[3-(4-n-octyl)-phenylthiophene] (POPT) from Grignard metathesis (GRIM) is reported. The GRIM POPT is found to exhibit favorable electronic, optical, and processing properties for organic photovoltaics (OPVs).

Several molecular dynamics simulations are conducted to explain the self-assembly and the structure-mobility relations observed in the various perylene tetracarboxydiimide derivatives. The derivatives are shown to exhibit a helical molecular arrangement, which favors hole transport suppressed by the structural defects of the system.

The article presents a new methodology that can be employed for the controlled synthesis of the PbS nanostructures with zero-, one- and two-dimensional structures. The degree of confinement of these nanostructures is shown to be highly dependent on the spatial dimensionality, hence making it useful for polarization-sensitive devices.

Four new DTS-BTD copolymers (P1-P4) differing by the concentration of electron-donating and -withdrawing substituents along the backbone are prepared and studied by 2D-WAXS and in bottom-contact FETs. All copolymers have self-assembled into lamellar superstructures, but only P2 and P4 have displayed a propensity to [pi]-stack and P4 has displayed a high hole mobility.

Single-molecule fluorescence spectroscopy is used to perform single-molecule detection of DNA hole transfer (DNA HT) and gain insight into the hole transfer process of individual DNA and the optical readout of DNA information at the single molecule level. The results confirmed the possible application of 'signal-on' detection system to detect DNA HT in individual DNA and the base-pair mismatch in the target DNA with high sensitivity and accuracy.

Molecular layers are designed that have enabled bistable switching on a surface and have demonstrated control of a single switch in a dense and ordered array at the spatial limit. Up and down motion of a central Sn ion through the frame of a phthalocyanine molecule is obtained from the resonant electron or hole injection into molecular orbits.

The small changes in the near-Fermi-level electronic structures of nonmodel supported catalysts, induced by the formation of surface alloys, are measured and related to the chemical and catalytic performance of these materials. A simple, physically transparent framework is described for predicting shifts in the d-band center in response to alloying and relating these shifts to the chemical characteristics of the alloy.

The photogenerated hole lifetime in Ti[O.sub.2] renders it the ability to split water molecule. Transient absorption spectroscopy over a range of excitation intensities is used to measure the hole lifetime and resulting oxygen production .

The studies related to the packing and binding interactions within the keto-steroid isomerase (KSI) active site that could constrain local side-chain reorientation and prevent hydrogen bond shortening is reported. The findings from the studies provide evidence for subtle geometric effects that could have significant energetic consequences.

The fabrication of the nanostructured liquid-crystalline materials consisting of the ion-conductive and hole transport layers built by the association of [pi]-conjugated molecules bearing ionic moieties is reported. The liquid crystals could be applied to various electronic devices such as light-emitting electrochemical cells as well as the electrochromic devices.

The framework of the electron-expansion methodology is used for calculating the weights of local covalent and ionic structures of a chemical bond from usual delocalized wave functions, where the hole conditions are expanded in terms involving only electrons. The three-electron populations are very important for bond localization, but in Charge-Shift bonds they are not important for the covalency/ionicity of these bonds.

The experimental and theoretical studies were conducted to determine the acid-base properties of the adenine cation radical produced by one-electron oxidation of dAdo and the stacked DNA-oligomer [(dA).sub.6] by [Cl.sub.2]* anion in aqueous glass. The results obtained showed that adenine cation radical isolated in solution and adenine cation radical in adenine stacks have highly differing acid-base properties resulting from the stabilization induced by hole delocalization within adenine stacks.

A new computational strategy is described for evaluating the charge-transfer (CT) parameters for hole transfer in DNA. Environmental effects are captured by using a quantum mechanics-molecular mechanics (QM/MM) coupling scheme and dynamical effects are included by evaluating the CT parameters along classical molecular dynamics simulations.