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Different concentrations of zinc phthalocyanines (Zn-Pc) in toluene solution are prepared and characterized in order to obtain best conditions for realizing the films in poly(methyl methacrylate) (PMMA). The findings reveal that comparison of linear and nonlinear absorption properties of the films and their Zn-Pc concentration in the PMMA matrix have shown that an enhancement of the nonlinear optical coefficient arises despite the evidence of the initial aggregation of molecules.

Nuclear motion modulation of electronic structure in a metal bridged phthalocyanine dimer, lutetium bisphthalocyanine, which displays two visible absorption bands is studied by exploiting a coherently excited nuclear wave packet. The nuclear coordinate influences the energies of the underlying exciton and charge resonance states as well as their interaction and the interplay of the various couplings creates unusual anti-correlated spectral motion in the two bands.

The functionalization of single-wall carbon nanotubes (SWNTs) with 4-(2-trimethylsilyl)ethynylaniline and the subsequent attachment of a zinc-phthalocyanine (ZnPc) derivative is described by using the reliable Huisgen 1,3-dipolar cycloaddition. The SWNT-ZnPc nanoconjugate is examined with a series of steady-state and time-resolved spectroscopy experiments and a photoinduced communication between the two photoactive components are identified.

The preparation and structural characterization, optical and electrochemical properties of unsymmetrically substituted mono and bistrithiolophthalocyanines is described. The ultraviolet-visible and/or NMR spectroscopy studies of the generation of cationic species upon treatment of phthalocyanines with TFA (trifluoroacetyl) are also described.

X-ray absorption spectroscopy was used to study the unoccupied electronic structure of potassium doped copper-phthalocyanine thin films. The result data revealed the filling of the lowest unoccupied molecular orbital upon doping and related changes of the core level absorption spectra.

Time-dependent density functional theory (TDDFT) approach and different exchange-correlation functionals are used for predicting the vertical excitation energies in zinc phthalocyanine (PcZn). The studies have shown that TDDFT method can be used for the accurate prediction of vertical excitation energies in phthalocyanines within a large energy range.

The desorption of [F.sup.-] ions from FCuPc films is used for monitoring damaging processes and accessing their nature under low-energy electron irradiation. The strong influence of energy redistribution is emphasized, which has quenched the long-lived negative ion resonances and has selected localized and strongly repulsive excitations.

The vibrational frequency shifts caused by electron addition to metal phthalocyanine (MPc) molecules are identified and characterized. The features and parameters of the static Jahn-Teller effect are obtained as a byproduct in a phthalocyanine molecular ion.

Ultraviolet absorption and micro-Raman analyses are used for studying the polymorphism in the growth of titanyl phthalocyanine films on dielectric substrates. Hyperthermal beams have given unprecedented control on the growth, which has produced crystalline films with a controlled structure and different phases even at room temperature and on amorphous substrates, depending on the deposition rate.

The effect of atmospheric gases on the ionization energy (I) of titanyl phthalocyanine thin film is examined by using photoemission yield spectroscopy. The results have shown that the atmospheric effect by ambient air on I is mainly due to water vapor, although oxygen has also made significant contribution.

The synthesis and characterization of the Germanium phthalocyanine, GePc, and the reduced complexes like SiPc[(pyridine).sub.2] and GePc[(pyridine).sub.2] are described. The analysis reveals that these complexes contain various antiaromatic [pi]-electron circuits.

The effect of the donor-acceptor (DA) linker chain length on the electron-transfer (ET) efficiency between CdSe quantum dots (QDs) and a series of Si phthalocyanines are studied with steady state and femtosecond time-resolved spectroscopy. An additional non-Forster-type energy transfer (ET) is observed, which is related to a surface DA interdigitization effect that can occur for QD-based DA systems.

The electronic structure of potassium-doped copper phthalocyanine (CuPc) using photoemission spectroscopy is studied. None of the films prepared revealed a finite electron density of states at the Fermi level (E(sub F)), which is in contrast to reports in the literature.

Theoretical computations based on time dependent density functional theory and multiconfigurational complete active space is used to study the photophysics of free-base hemiporphyrazine. The results confirm that the dual emission spectrum of hemiporphyrazine is due to the formation at the excited state of different tautomers.