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Pozycja Proper conformal symmetries in self-dual Einstein spaces(2014) Chudecki, Adam; Dobrski, MichałProper conformal symmetries in self-dual Einstein spaces are considered. It is shown that such symmetries are admitted only by the Einstein spaces of the type [N,−]⊗[N,−][N,−]⊗[N,−] . Spaces of the type [N]⊗[−][N]⊗[−] are considered in details. Existence of the proper conformal Killing vector implies existence of the isometric, covariantly constant, and null Killing vector. It is shown that there are two classes of [N]⊗[−][N]⊗[−] -metrics admitting proper conformal symmetry. They can be distinguished by analysis of the associated anti-self-dual (ASD) null strings. Both classes are analyzed in details. The problem is reduced to single linear partial differential equation (PDE). Some general and special solutions of this PDE are presented.Pozycja Bipolar transport of charge carriers in thin films of 9,10-dimethylanthracene and 1-acenaphthenol.(Lodz University of Technology Press, 2014) Kania, Sylwester; Kuliński, Janusz; Marciniak, Bernard; Różycka-Sokołowska, EwaThe current-voltage (I-U) characteristics we have been measured for thin films of 1-acenaphthenol and 9,10-dimethylanthracene prepared from their commercially available materials as products with purity >_ 10-3 mass %. Using the method of differential processing of the characteristics, charge transport mechanism in these films was assessed.Pozycja Conditions for having a diffeomorphism between two Banach spaces(Department of Mathematics - Texas State University, 2014) Galewski, Marek; Galewska, Elżbieta; Schmeidel, EwaWe provide sufficient conditions for a mapping acting between two Banach spaces to be a diffeomorphism. Standart arguments allow us to obtain a local diffeomorphism. It is proved to be global using mountain pass geometry.Pozycja On a new critical point theorem and some applications to discrete equations(AGH University of Science and Technology Press, 2014) Galewski, Marek; Galewska, ElżbietaUsing the Fenchel-Young duality we derive a new critical point theorem. We illustrate our results with solvability for certain discrete BVP. Multiple solutions are also considered.Pozycja Correlated networks in the adsorptionenhanced currents(Lodz University of Technology Press, 2014) Kania, Sylwester; Kuliński, JanuszInjection of carriers into thin layers of acenes due to adsorption of ethanol activator molecules is considered as a electron transfer reaction between two phases. Complexity of the processes may be diminished with applying electron transfer theory in the meaning of Marcus.Pozycja Effect of molecule dipolemoment on hole conductivity of polycrystalline anthrone and anthrachinone layers.(Wydawnictwo Politechniki Łódzkiej, 2015) Kania, Sylwester; Kościelniak-Mucha, Barbara; Kulinski, Janusz; Słoma, PiotrComplex analyzes were made using methods of molecular quantum mechanics to investigate the effect of the dipole moment of the molecule carrier drift mobility in polycrystalline layers composed of anthrone and anthrachinone molecules. The differences in the measured mobility values seems to be originated in the variations of the geometry of the frontier orbitals rather than the differences inherent in the crystal arrangement of these molecules, which after all, for both are nearly identical.Pozycja Dielectric properties of ferroelectric liquid crystalline material with chiral nematic phase.(Wydawnictwo Politechniki Łódzkiej, 2015) Wojciechowski, Marek; Bąk, Grzegorz W.; Tykarska, MarzenaThe ferroelectric liquid crystal with nematic N* phase has been investigated using broadband low frequency dielectric spectroscopy. The dielectric relaxation modes related to a ferroelectric Goldstone mode were detected only in a narrow temperature range. Well defined relaxation process was detected in the SmB* phase at about 90 Hz.Pozycja Spline interpolation for trap spectroscopy analysis for two cyclic hydrocarbons.(Wydawnictwo Politechniki Łódzkiej, 2015) Kania, Sylwester; Kuliński, JanuszCubic spline interpolation gives a tool for obtaining good image of current-voltage characteristics for trap spectroscopy analysis without prior assumption about the trap distribution for 1-acenaphthenol and 9,10-dimethylanthracene.Pozycja Adsorption induced hole transport in thin layers of non-ordered tetracene.(Wydawnictwo Politechniki Łódzkiej, 2015) Kania, Sylwester; Kuliński, JanuszAdditional disorder induced by adsorption processes by the molecule of ambient are responsible for deep modulation of conductivity. Observations confirmed the dominated role of the increase of the free carrier concentration due to the increse the shallow trap concentration, for modulation of the conductivity.Pozycja Elimination of the impact of rc constant on transient photocurrents measured in organic layers.(Wydawnictwo Politechniki Łódzkiej, 2016) Kania, Sylwester; Kuliński, JanuszWe present a calculation method for elimination of the effect of the RC constant of the measuring circuit in the time-of-flight (TOF) measurements where a pulse generation of the photocurrent in a thin layer of low-molecular organic material is exploited. Presented method allows to eliminate the influence of the component of displacement current related to dielectric losses and obtaining the actual conduction current time dependence. The method was tested on the thin layers of 1,5-dihydroxynaphthalene.Pozycja The effect of symmetry of a molecule electronic density on the dipole moment of unit cell and hole conductivity of thin polycrystalline films of anthrone and anthraquinone.(Wydawnictwo Politechniki Łódzkiej, 2016) Kania, Sylwester; Kościelniak-Mucha, Barbara; Kuliński, Janusz; Słoma, Piotr; Wojciechowski, KrzysztofThe electronic structure of anthrone and anthraquinone molecules in the gas state and in the simulated crystal unit cell were calculated with time dependent-density functional theory (TD-DFT) method. The values of dipole moment of single molecule and of single crystal unit cell were also determined with TD-DFT method. The results of TD-DFT were compared with known crystal structures of both compounds [1,2]. For both molecules it was observed improvement of matching the length of corresponding bonds when calculated for the unit cell. Unexpectedly high value of dipole moment was calculated for the single unit cell of anthrone. This fact can be responsible for the nano-dimension properties of anthrone as the carriers mobility or high boiling point.Pozycja Comparative study of the influence of the reorganization energy on the hole transport of two four-cyclic arenes(Wydawnictwo Politechniki Łódzkiej, 2017) Kania, Sylwester; Kuliński, Janusz; Sikorski, DominikApplication of the method of quantum-mechanical calculations allowed the determination of the reorganization energy of the molecules of tetracene and p-quaterphenyl and the estimation of the transfer rate integral between neighbouring molecules present in the solid state. Comparison of the transfer rates for holes with the values of the mobility, obtained experimentally for the polycrystalline tetracene layers and p-quaterphenyl layers vaporized in the vacuum in the similar conditions indicate that the molecule’s structure possess the dominate impact on the conductivity of the thin layers of these compounds.Pozycja The effect of the dipole moment on hole conductivity of polycrystalline films of two anthracene derivatives(Wydawnictwo Politechniki Łódzkiej, 2017) Kania, Sylwester; Kościelniak-Mucha, Barbara; Kuliński, Janusz; Słoma, Piotr; Wojciechowski, KrzysztofHole mobility in the polycrystalline layers of anthrone and anthraquinone differs in one order of magnitude in spite of nearly the same crystalline structure. The origin of this difference was determined with use of the quantum-mechanical calculations carried out at the density functional theory level using the B3lYP functional in conjunction with the 6-311++G(d,p) basis set. Based on theses calculations, we suppose that these difference can result from the presence of the dipol moment in the anthrone molecules.Pozycja Sensitivity of tetracene layer as an effect of entanglement(Wydawnictwo Politechniki Łódzkiej, 2017) Kania, Sylwester; Kościelniak-Mucha, Barbara; Kuliński, Janusz; Słoma, Piotr; Wojciechowski, KrzysztofApplication of the method of quantum-mechanical calculations allowed for studies of variability of interactions between molecules of ethanol and tetracene. Entanglement of quantum states is seen during calculations in two ways: as a change of electric dipole moment and as an increase of the basis set superposition error (BSSE) with decreasing distance between molecules under study. There are observed the dependences of the total energy of the system due to the mutual arrangement of the long axes of the molecules and due to the orientation of the bond of the oxygen atom to the carbon atom with respect to the plane of benzene skeleton of tetracene molecule.Pozycja Ab initio investigation of ethanol-tetracene interactions during adsorption(Wydawnictwo Politechniki Łódzkiej, 2018) Kania, Sylwester; Kościelniak-Mucha, Barbara; Słoma, Piotr; Wojciechowski, KrzysztofAb initio calculations presented in this work are performed to investigate the geometry, interaction energy and bonding properties of binary complexes formed between neutral ethanol and tetracene molecules. Two different geometries were applied for the study. The interaction energies between molecules in the complex posses minimum at the distance of about 3.6 A among oxygen atom in ethanol and the neighbouring carbon atom of tetracene skeleton.Pozycja The origin of the interaction responsible for the difference of hole mobility of thwo derivatives of anthracene(Wydawnictwo Politechniki Łódzkiej, 2018) Kania, Sylwester; Kuliński, Janusz; Sikorski, DominikHole mobility of the layers built from two anthracene derivatives differing in the substitution of the central benzene ring, i.e. anthrone substituted with only one keto group and anthraquinone substituted with two keto groups differs by one order of magnitude despite the fact that both have almost identical crystal structure. We ascribe this difference to existence of an additional intermolecular interaction arising in the layer of anthrone.Pozycja Electrical and thermal properties of anthraquinone layers(Lodz University of Technology Press, 2019) Kania, Sylwester; Kuliński, Janusz; Sikorski, DominikQuantum-chemical calculations indicate that the bond lengths in the anthraquinone anthracene backbone are shorter than the corresponding bonds in unsubstituted anthracene. The shape of the frontier molecular orbitals (FMO) indicates the possibility of more efficient electron capture by the anthraquinone molecule than by the anthracene molecule while maintaining stability in the conditions prevailing in electrochemical cells. Differential scanning calorimetry (DSC) studies indicate the temperature stability of anthraquinone above the melting point up to 300C. The glass transition is determined at about 100°C.Pozycja Polarization of organic aromatic molecule in anionic and cationic state(Lodz University of Technology Press, 2019) Kania, Sylwester; Kościelniak-Mucha, Barbara; Kuliński, Janusz; Słoma, Piotr; Wojciechowski, KrzysztofThe modification of electron states and the change in the geometry of the structure of molecule during hopping transport of charge carriers depends on the symmetry of the molecule. During electric transport the molecule reversibly transforms from neutral state to cation when hole conductivity occurs or to anion when electron conductivity occurs. The energies of orbitals HOMO and HOMO1 of anthrone and anthrachinone are always negative, what allows for holes transport. Positive energies of LUMO and LUMO+1 orbitals of anion of anthrone and anthraquinone in structure of anion or neutral molecule make electron transport difficult.Pozycja Charge carrier mobility in non-equilibrated transport in molecular materials(Lodz University of Technology Press, 2019) Kania, Sylwester; Kościelniak-Mucha, Barbara; Kuliński, Janusz; Słoma, Piotr; Wojciechowski, KrzysztofNon-equilibrated transport of charge carriers in the molecular material depends on the structure and packing of the molecules. Explanation of the measurements of the photocurrent generated with use of UV flash light in organic layer needs to define the quantity of charge carriers mobility. Definition of this quantity in the scope of some defined transport model requires the detailed analysis of generation, recombination and charge transfer between neighbouring molecules. The problem is discuss on the basis of transport properties of two anthracene derivativesPozycja Andrzej Dems (1938-1988)(Wydawnictwo Politechniki Łódzkiej, 2020) Dems-Rudnicka, Katarzyna; Stawski, DawidW trzydziestą rocznicę śmierci Andrzeja Demsa wspominali Go uczestnicy konferencji Central European Conference Fibre Grade Polymers, Chemical Fibres and Special Textiles związanej z tematyką badawczą, nad którą pracował.