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The Franck-Condon (FC) factors for the lowest energy molecular nature electronic transition was calculated by employing ground- and excited-state geometries to determine the origin of the intensity of 0 -> 0 and 0 -> 1 vibronic bands.

Hexabutoxytriphenylene is used for the synthesis of hexabutoxytribenzo[a,g,m]coronenes. The analysis has shown that these molecules can adopt a 'double concave' conformation, thus making them ideal hosts for the binding of different guest molecules at each face.

The series of trigonal molecules made up of a central truxene core with peripheral oligofluorene branches of variable lengths is analyzed for molecular and electronic features. The electronic interactions are found to be the functions of some key intensity ratios in the Raman spectra.

The synthesis and photophysical properties of para- and meta-linked alkynylpyrene oligomers are presented. The absorption and fluorescent spectra have shown para-linked oligomers to be [pi]-conjugated when compared to meta-linked ones and the fluorescence quantum yields are decreased with increasing oligomer length.

A method for the measurement of 24 hydroxylated polycyclic aromatic hydrocarbon metabolites (OH-PAHs) in urine has been developed. The method is based on enzymatic deconjugation, automated liquid--liquid extraction, and gas chromatography/isotope dilution high-resolution mass spectrometry after derivatization of the OH-PAHs to the trimethylsilylated derivatives. The metabolites included in the current method are formed from eight different parent compounds. The limits of detection were below 7 pg/mL when using a sample size of 2 mL of urine, except for 1- and 2-naphthols (18 and 12 pg/mL, respectively). The enzymatic deconjugation efficiency, verified by deconjugation of urine samples spiked with [alpha]-naphthyl [beta]-D-glucuronide sodium salt (1-NAP-GLU) and pyrene-1-sulfate potassium salt (1-PYR-SULF), was determined to be 97% for 1-NAP-GLU conjugate and 84% for 1-PYR-SULF. The overall coefficients of variance for six batches of quality control samples (n = 42), was 2.9-11%. Mean method recoveries of the [sup.13]C-labeled internal standards were 66-72%, except for [sup.13][C.sub.6-1-naphthol (46%). The throughput of this method has been determined to be 40 samples per day per analyst. This method is currently applied to epidemiological studies, such as the National Exposure and Nutrition Examination Survey (NHANES), to measure human exposure to PAHs.

The first isolation and identification of two arene oxides from hexabromoantharacene and other derivatives of anthracene from hexabromoanthracene are described. The study aims to elaborate the conversions and to illustrate the potential utility of isomeric anthracene oxides for the synthesis of polysubstituted anthracene derivatives that are difficult to synthesize using other routes.

The infrared vibrational and UV-visible electronic absorption spectra of 2,3-benzofluorene and its cation trapped in solid Ar are analyzed. The unidentified infrared (UIR) bands, contributed by the 2,3-benzofluorene cation and observed in the interstellar space are discussed.

The synthesis, as well as the different properties of a newly formulated teranthene derivative is discussed. The biradical character exhibited by the compound in its ground state is also analyzed.

A new PCR primer system that targets a wide range of polycyclic aromatic hydrocarbon ring-hydroxylating dioxygenase ([PAH-RHD.[alpha]]) gene of both Gram-positive and Gram-negative bacteria was developed and used to study their abundance and diversity in two different soils in response to phenanthrene spiking. The results obtained from the analysis of amplicons confirmed the specificity of the newly developed primer system and revealed a soil type-dependent response of [PAH-RHD.sub.[alpha]] gene-carrying soil bacteria to phenanthrene spiking.

A new method based on synchronous fluorescence observations of [super 14]C-pyrene was developed for continuously measuring the uptake of dissolved pyrene by Mycobacterium gilvum VM552, a representative degrader of polycyclic aromatic hydrocarbons (PAHs). The findings from the study might find relevant use for bioaccumulation scenarios that consider the effect of sediment resuspension events on exposure to water column and sediment pore water as well as the direct uptake of PAHs from sediments.

High exo-facial selectivity is seen in the selective monohydrolysis of a series of near-symmetric diesters that possess an exo-ester group and endo-ester group attached on a norbornane or norbornene skeleton. The effect of the co-solvent for the selective monohydrolysis reaction is contributed to improvement of the yields of the half-esters.

Density functional theory is used to demonstrate the possible way to control the charge-transport parameters of perylene tetracarboxylic diimides (PTCDIs) as a function of the type, number, and positions of the substituents. The results indicated that large bandwidths along with small effective masses could be obtained with the insertion of appropriate substituents on the nitrogens, in particular halogenated aromatic groups.

Novel fused-ring bicyclic and tricyclic nicotine derivatives are prepared from natural (S)-nicotine. Enantiopure bicyclic dioxino, dihydrofuro and dihydropyranol nicotine derivatives as well as tricyclic benzofuro and benzopyran derivatives are prepared from simple alkoxy or halonicotine intermediates.

The article explains a new technique, which can be easily employed for studying the solvation free energies of oil in water. The analysis proves that the molecular shape and the size are the most important factors that affect the oil/water transfer in a system.

The transformation of two-dimensional graphene oxide (GO) nanosheets into carbon nanotubes is achieved by sonicating GO in 70% nitric acid. The cavitation-induced condensation of the polyaromatic hydrocarbons (PAHs) has resulted in their molecular reconstruction to form folded carbon nanostructures.

The preparation of substituted calix[4]azulenes through reaction between 6-alkylazulenes and paraformaldehyde in the presence of florisil is reported. Hydride abstraction of a calix[4]azulene with [Ph.sub.3]CP[F.sub.6] produced tetraazulene analogue of the porphodimethenes.

An efficient synthesis of dibenzo[a,m]rubicenes and tetrabenzo[a,f,r,m]rubicenes involving ICl-mediated benzannulation of 1,4-diphenyl-2,5-dialkynylbenzene as the key step is described. The photophysical properties of the new indeno-PAHs are analyzed.

Tailor-made synthesis and structure-property relationship of several swallow-tail N-substituted perylene bisimide (PBI) dyes are presented. The results suggested that the inherent tendency of PBI molecules for crystallization could be effectively suppressed by incorporating flexible OEG swallow-tail units only at imide positions.

UV-vis spectroscopic studies were conducted to determine the contribution of [C.sup.8]-aryl moiety and [N.sup.7] p[K.sub.a1] values and hydrolysis kinetics, while density functional theory (DFT) calculations were used to probe the structural features and stability of the [C.sup.]8-aryl-dG adducts bearing different para and ortho substituents.The information gained from the study facilitated development of a new rationale for the tendency of abasic site formation to accompany [C.sup.8]-arylpurine adduction within duplex DNA at neutral pH.

Photoinduced charge separation in pyrene-based bichromophoric systems has provided an effective strategy in organic synthesis, which is shown for the [2+2] cycloaddition between 1,3-cyclohexadiene and styrenes as a model reaction.

Palladium-catalyzed cocyclotrimerization of allenes with arynes is developed for selectively preparing phenanthrenes. A variety of allenes have undergone the cocyclotrimerization with arynes to produce the corresponding phenanthrenes in the presence of [[(allyl)PdCl].sub.2] and P[(o-tol).sub.3].

The reaction energetics of 43 1,4-dihydrogenation reactions of polycyclic aromatic hydrocarbons and nitrogen-containing heterocycles as well as the 43 analogues Diels-Alder reactions with ethylene ([C.sub.2][H.sub.4]) are analyzed by using density functional theory (DFT) calculations. The transition state distortion energies have correlated with the activation energies of these reactions, even for cases when energies of reaction do not correlate with reactivities.

The fabrication of two distinct supramolecular species of perylene bisimide by mixing melamine-appended perylene bisimides (MPBIs) and cyanurates is described. Supramolecular architectures are determined by the number of carbon atoms at the linker moieties of MPBIs and can be applied to generate a variety of other functional [pi]-conjugated molecules.

The femtosecond-resolved transient absorption spectroscopy is employed to study the photophysics and the excited-state dynamics of nitroperylene (NPe) in solvents with different properties. The excited-state dynamics of NPe is shown to be highly dependent on the wavelength and the polarity of the solvent.

Several studies are conducted to explain the mechanism associated with the palladium, Pd(II) phthalocyanine-sensitized triplet-triplet annihilation (TTA) of the rubrene acceptor molecules. The rubrene molecules are shown to emit yellow singlet radiations upon red excitation of the Pd compound.