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The electronic structure and spectra of two novel pentapyrrolic macrocycles compounds and the isomers of smaragdyrin are examined using spectral and theoretical techniques. The results from spectral pattern that four lowest excited electronic singlet states of both compounds are in good agreement with a four-orbital model was widely used to describe the spectral analysis of such similar compounds.

Molecular dynamics and DFT studies of intermolecular hydrogen bonds between bifunctional heteroazaaromatic molecules and hydrolic solvents are carried out. The experiment indicates that these molecules form different types of intermolecular complexes with hydroxylic solvents in the ground electronic state.

Electronic absorption and magnetic circular dichroism were recorded for five cyclophanes with ethano bridges: [2.2]paracyclophane, (1,2,4)[2.2.2]cyclophane, (1,2,4;1,2,5)[2.2.2]cyclophane, (1,2,3,4,5,6)(1,2,3,4,5,6)cyclophane, and trans-[2.2]metacyclophane. Spectral and structural analyses were based on geometry optimization and calculations of transition energies, carried out using density functional theory methods. The assignments have been proposed for several electronic transitions observed in the region below 52 000 cm-1. The observation of transitions which should be forbidden in the high D2h symmetry [2.2]paracyclophane suggests a twisted ground state structure of D2 symmetry, although the former structure with large amplitude vibrations at room temperature cannot be excluded. The PBE0 functional turned out to appropriately reproduce the inter-ring distances and electronic transition energies. [ABSTRACT FROM AUTHOR]

Proton transfer reaction is studied for 1H-pyrrolo[3,2-h]quinoline-water complexes [(PQ-([H.sub.2]O).sub.n], n=0-2) in the ground and the lowest excited singlet states at the density functional theory (DFT) level. The excited-state acid-base changes introduce a driving force for the proton transfer reaction, large relaxation and reorganization of the hydrogen bonded water bridge in [(PQ-([H.sub.2]O).sub.2] are required during the proton translocation from the pyrrole NH group to the quinoline nitrogen blocking the complete tautomerization in this type of solvate.

A study is conducted to examine few carbazole-related compounds in alcoholic solution, photoinduced solute--solvent proton-transfer dynamics, by means of femto- and picosecond fluorescence transient measurements. The results are suggestive of a thermally averaged deuteron tunneling process in the cyclic solute--solvent complex.

Anharmonicity plays a crucial role in hydrogen transfer reactions in hydrogen-bonding systems, which leads to a peculiar spectral line shape of the hydrogen stretching mode as well as highly complex intra/intermolecular vibrational energy relaxation. Single-molecule study with a well-defined model is necessary to elucidate a fundamental mechanism. Recent low-temperature scanning tunnelling microscopy (STM) experiments revealed that the cis↑cis tautomerization in a single porphycene molecule on Cu(110) at 5 K can be induced by vibrational excitation via an inelastic electron tunnelling process and the N–H(D) stretching mode couples with the tautomerization coordinate [Kumagai et al. Phys. Rev. Lett. 2013, 111, 246101]. Here we discuss a pronounced anharmonicity of the N–H stretching mode observed in the STM action spectra and the conductance spectra. Density functional theory calculations find a strong intermode coupling of the N–H stretching with an in-plane bending mode within porphycene on Cu(110). [ABSTRACT FROM AUTHOR]

We describe various experimental approaches that have been used to obtain a detailed understanding of double hydrogen transfer in porphycene, a model system for intramolecular hydrogen bonding and tautomerism. The emerging picture is that of a multidimensional tautomerization coordinate, with several vibrational modes acting as reaction-promoters or inhibitors through anharmonic intermode coupling. Tunnelling processes, coherent in the case of isolated molecules and incoherent in condensed phases, are found to play a major role even at elevated temperatures. Single-molecule spectroscopy studies reveal large fluctuations in hydrogen transfer rates observed over time for the same chromophore. Scanning probe microscopy is employed to directly observe the structure and tautomerization dynamics of single molecules adsorbed on metal surfaces and demonstrates how the interactions of the molecules with atoms of the supporting surface affect their static and dynamic properties: different tautomeric forms are stabilized for molecules depending on the surface structure and the reaction mechanism can also change, from a concerted to a stepwise transfer. The scanning probe microscopy studies prove that tautomerization in single molecules can be induced by different stimuli: heat, electron attachment, light, and force exerted by the microscope's tip. Possible applications utilizing tautomerism are discussed in combination with molecular architectures on surfaces, which could pave the way for the development of single-molecule electronics. [ABSTRACT FROM AUTHOR]

Tekst przedstawia rozważania na temat pozytywnych aspektów wykorzystania mediacji jako formy sprawiedliwości Autorka artykułu przybliża w nim charakterystyczne cechy pojęcia sprawiedliwości naprawczej poprzez przybliżenie jego typowych dla niego znamion. W tekście przedstawiona zostaje także analiza porównawcza sprawiedliwości naprawczej i karnej jak również wymienione zostają możliwe nadużycia będące wynikiem instytucjonalnego zawłaszczenia mediacji. Autorka artykułu podkreśla przede wszystkim obustronne korzyści (zarówno dla sprawcy i pokrzywdzonego, jak również dla społeczeństwa, ale i wymiaru sprawiedliwości) wynikające ze stosowania mediacji, takie jak: odciążanie wymiaru sprawiedliwości od spraw uważanych za drobne, możliwość zadania pytań przez pokrzywdzonego i przebaczenie sprawcy, współuczestniczenie w rozwiązaniu własnej sprawy i możliwość przeproszenia a tym samym zrozumienia – jakąś i komu krzywdę wyrządził oraz przywrócenie społecznego zaufania do wymiaru sprawiedliwości a tym samym edukacji prawnej społeczeństwa. W podsumowaniu J. Waluk zachęca do wprowadzenia w społecznościach lokalnych konferencji sprawiedliwości naprawczej, których celem miałyby być zainteresowanie tym rozwiązaniem władz lokalnych i samorządowych.