https://eczasopisma.p.lodz.pl/PHYSICS <p>The journal publishes articles of employees and students of the Institute of Physics, Technical University of Lodz, employees of the Center for Teaching Mathematics and Physics, and employees of other universities, regarding the latest research in all areas of physics. One issue is published every year. The journal is published in English. All works are reviewed. The journal is indexed in the BazTech database.</p> Wydawnictwo Politechniki Łódzkiej en-US Scientific Bulletin. Physics 1505-1013 https://eczasopisma.p.lodz.pl/PHYSICS/article/view/479 <p>The nature of intermolecular interactions for anthrone and anthraquinone differs due to the symmetry of substitution of the central benzene ring, i.e. anthrone substituted with only one keto group and anthraquinone substituted with two keto groups. In order to interpret the interactions among the molecules, the interaction energies between molecules in crystals were calculated using DFT B3LYP calculations. The results reveal the consistency between calculated “lattice energies” and theirs terms and thermodynamical properties as density, boiling point and melting point of examined compounds.</p> Sylwester Kania Janusz Kuliński Barbara Kościelniak-Mucha Piotr Słoma Krzysztof Wojciechowski Copyright (c) 2021-12-30 2021-12-30 42 1230 5 12 10.34658/physics.2021.42.5-12 https://eczasopisma.p.lodz.pl/PHYSICS/article/view/481 <p>Volume conductivity of thin organic layers in contact with the ambient atmosphere depends on the volume properties and on the adsorption processes on the free surface of the layer. In order to clarify the role of the surface, experiments were carried out at a temperature close to 293 K to determine the influence of the adsorption dynamics on the change of characteristic relationships observed for the transport of electric charge in vacuum, in the ambient atmosphere and in the controlled atmosphere of the ethyl alcohol vapors. The investigations were carried out for two linear tetracyclic molecular structures, i.e. p-tetraphenyl and tetracene. These molecular systems differ in organization of the rings. The results show an increase in conductivity measured for both compounds when there are the molecules capable of adsorbing to the surface and to transfer or receive charge carriers connected with the process of diffusion or drift transport in the volume of the layer. The nature of the observed increase in conductivity proves that the hopping mechanism is present in the case of conductivity of both tested materials.</p> Sylwester Kania Janusz Kuliński Barbara Kościelniak-Mucha Piotr Słoma Krzysztof Wojciechowski Copyright (c) 2021-12-30 2021-12-30 42 1230 13 31 10.34658/physics.2021.42.13-31