Condensed Matter Physics
https://cmpj2.icmp.lviv.ua/index.php/cmpj
<p><strong>Condensed Matter Physics</strong> contains original and review articles in the field of statistical mechanics and thermodynamics of equilibrium and nonequilibrium processes, relativistic mechanics of interacting particle systems.The main attention is paid to physics of solid, liquid and amorphous systems, phase equilibria and phase transitions, thermal, structural, electric, magnetic and optical properties of condensed matter. <strong>Condensed Matter Physics </strong>is a diamond open-access, international peer-reviewed scientific journal published quarterly.</p> <p><span id="main"><strong><tt>ISSN 1607-324X (print), 2224-9079 (online)</tt></strong></span></p> <p>Key title: <strong>Condensed Matter Physics</strong><br />Abbreviated key title: <strong>Condens. Matter Phys.</strong> </p>Institute for Condensed Matter Physics of the National Academy of Sciences of UkraineenCondensed Matter Physics1607-324XCrossing the disciplines - a starter toolkit for researchers who wish to explore early Irish literature
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/88
<p>The inspiration behind this paper came from both authors’ long-term collaboration with our friend and colleague, Professor Ralph Kenna. This connection emerged initially through his interest in Rathcroghan and in our paper, ‘Exploring the Nature of the Fráoch Saga’, which we concluded with the statement that we believed it ‘presents a case that will hopefully ignite conversation between disciplines’. This led us to consider the potential value for researchers of compiling a template list of useful and reliable sources and resources to consult, in other words a type of starter toolkit or guide for any individual from an alternative discipline or background, who might possess, or, in time, develop a personal or professional interest in Early Ireland and Early Irish literature. In doing this, we decided for ease of illustration, to take the example of the location name Rathcroghan/Cruachan Aí, (the prehistoric Royal Site of Connacht in the west of Ireland and the place that we both work in and interact with on a daily basis), as a case study in order to demonstrate an initial methodological approach to not only the types of resources and information available, but also to highlight some potential pitfalls that may arise in the course of an investigation.</p>
ArticlesStatistical PhysicsComplex Systemssocial networksmythologyM. McCarthyD. P. Curley
Copyright (c) 2024 M. McCarthy, D. P. Curley
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2024-09-242024-09-24338043380410.5488/cmp.27.33804Richard Kirwan a [united] Irish man of science in Europe
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/77
<p>The late eighteenth and early nineteenth centuries have long been considered as a formative period for modern Irish political traditions such as nationalism, republicanism and unionism. For Europe it was the time of a turnover in science moving from observation to experiment and from speculation to fact. Richard Kirwan was a well known natural philosopher in Europe and a respected man of science in his time. Throughout all the wars, he was connected with his colleagues in a network reaching across Europe and even to America. Using a few examples, this article is intended to provide an insight how the network worked in a time that was marked by political conflicts and revolutionary events in both science and social life.</p>
ArticlesStatistical Physicshistory of sciencehistory of physicsnatural scienceR. Folk
Copyright (c) 2024 R. Folk
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2024-09-242024-09-24331013310110.5488/cmp.27.33101Differential geometry, a possible avenue for thermal ablation in oncology?
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/78
<p>We report a model for hyperthermia therapies based on heat diffusion in a biological tissue containing a topological defect. Biological tissues behave like active liquid crystals with the presence of topological defects which are likely to anchor tumors during the metastatic phase of cancer evolution and the therapy challenge is to destroy the cancer cells without damaging surrounding healthy tissues. The defect creates an effective non-Euclidean geometry for low-energy excitations, modifying the bio-heat equation. Applications to protocols of thermal ablation for various biological tissues (liver, prostate, and skin) is analyzed and discussed.</p>
ArticlesStatistical PhysicsComputer Modellingdifferential geometrybioheat transportthermal ablationA. ManapanyL. DidierL. MoueddeneB. BercheS. Fumeron
Copyright (c) 2024 A. Manapany, L. Didier, L. Moueddene, B. Berche, S. Fumeron
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2024-09-242024-09-24332013320110.5488/cmp.27.33201On a previously unpublished work with Ralph Kenna
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/79
<p>This is part of an unpublished work in collaboration with Ralph Kenna. It was probably not mature enough at the time it was submitted more than ten years ago and it was rejected by the editors, but some of the ideas had later been published partially in subsequent works. I believe that this “draft” reveals a lot about Ralph’s enthusiasm and audacity and deserves to be published now, maybe as a part of his legacy.</p>
ArticlesStatistical Physicsuniversalityfinite-size scalingupper critical dimensionR. KennaB. Berche
Copyright (c) 2024 R. Kenna, B. Berche
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2024-09-242024-09-24336023360210.5488/cmp.27.33602Partition function zeros of zeta-urns
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/80
<p>We discuss the distribution of partition function zeros for the grand-canonical ensemble of the zeta-urn model, where tuning a single parameter can give a first or any higher order condensation transition. We compute the locus of zeros for finite-size systems and test scaling relations describing the accumulation of zeros near the critical point against theoretical predictions for both the first and higher order transition regimes.</p>
ArticlesStatistical PhysicsLee-Yang and Fisher zeroescritical exponentsfirst order phase transitionssecond order phase transitionsP. BialasZ. BurdaD. A. Johnston
Copyright (c) 2024 P. Bialas, Z. Burda, D. A. Johnston
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2024-09-242024-09-24336013360110.5488/cmp.27.33601Ising model with varying spin strength on a scale-free network: scaling functions and critical amplitude ratios
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/81
<p>Recently, a novel model to describe ordering in systems comprising agents which, although matching in their binarity (i.e., maintaining the iconic Ising features of “+” or “–”, “up” or “down”, “yes” or “no”), still differing in their strength was suggested [Krasnytska et al., J. Phys. Complex., 2020, <strong>1</strong>, 035008]. The model was analyzed for a particular case when agents are located on sites of a scale-free network and agent strength is a random variable governed by a power-law decaying distribution. For the annealed network, the exact solution shows a rich phase diagram with different types of critical behavior and new universality classes. This paper continues the above studies and addresses the analysis of scaling functions and universal critical amplitude ratios for the model on a scale-free network.</p>
ArticlesStatistical PhysicsComplex Systemsphase transitionsIsing modeluniversalityscaling functionscritical amplitude ratioscomplex networkM. Krasnytska
Copyright (c) 2024 M. Krasnytska
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2024-09-242024-09-24336033360310.5488/cmp.27.33603Revisiting the Lee-Yang singularities in the four-dimensional Ising model: a tribute to the memory of Ralph Kenna
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/83
<p>We have studied numerically the Lee-Yang singularities of the four dimensional Ising model at criticality, which is believed to be in the same universality class as the φ<sub>4</sub><sup>4 </sup>scalar field theory. We have focused in the numerical characterization of the logarithmic corrections to the scaling of the zeros of the partition function and its cumulative probability distribution, finding a very good agreement with the predictions of the renormalization group computation on the φ<sub>4</sub><sup>4</sup> scalar field theory. To obtain these results, we have extended a previous study [R. Kenna, C. B. Lang, Nucl. Phys., 1993, B393, 461] in which there were computed numerically the first two zeros for <em>L</em>≤24 lattices, to the computation of the first four zeros for <em>L</em>≤64 lattices.</p>
ArticlesStatistical PhysicsComputer Modellingrenormalization groupscalinglogarithmsmean fieldcomplex singularitiesJ. J. Ruiz-Lorenzo
Copyright (c) 2024 J. J. Ruiz-Lorenzo
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2024-09-242024-09-24336043360410.5488/cmp.27.33604Statistical physics and emergent behaviour: from spin models to cultural complexity. In memory of Ralph Kenna (27.08.1964-26.10.2023)
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/84
<p>It’s been sixty years since Ralph’s birth day and soon it will be one year since he left us. Initially, this collection of papers was being prepared as a Festschrift - a birthday greeting, and now it is published in his memory. It is difficult to write this foreword, because Ralph is not only a fellow physicist and a close collaborator, he is a very close friend. It is also difficult to write because, in a short text, it is hard to reflect the versatility of his gifts: from statistical physics to field theory, from the science of complex systems to quantitative methods in social sciences and humanities, from scientometrics to history of physics. This is not a complete list of areas that he enriched thanks to his talent and hard work. What’s more, his activities in scientific research are inseparable from his public activities, be it the protection of historical heritage or the restoration of historical memory in Ireland, his motherland, or the collection of funds for the fight against serious diseases in the UK, where he worked, or his participation in the organisation and evaluation of research work on a pan-European scale. The integrity of his personality is one of those features that first come to mind when we think about him, repeatedly.</p>
EditorialEditorialB. BercheR. FolkYu. HolovatchO. Mryglod
Copyright (c) 2024 B. Berche, R. Folk, Yu. Holovatch, O. Mryglod
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2024-09-242024-09-24301013010110.5488/cmp.27.30101Consensus decision making on a complete graph: complex behaviour from simple assumptions
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/85
<p>In this paper we investigate a model of consensus decision making [Hartnett A. T., et al., Phys. Rev. Lett., 2016, 116, 038701] following a statistical physics approach presented in [Sarkanych P., et al., Phys. Biol., 2023, 20, 045005]. Within this approach, the temperature serves as a measure of fluctuations, not considered before in the original model. Here, we discuss the model on a complete graph. The main goal of this paper is to show that an analytical description may lead to a very rich phase behaviour, which is usually not expected for a complete graph. However, the variety of individual agent (spin) features - their inhomogeneity and bias strength - taken into account by the model leads to rather non-trivial collective effects. We show that the latter may emerge in a form of continuous or abrupt phase transitions sometimes accompanied by re-entrant and order-parameter flipping behaviour. In turn, this may lead to appealing interpretations in terms of social decision making. We support analytical predictions by numerical simulation. Moreover, while analytical calculations are performed within an equilibrium statistical physics formalism, the numerical simulations add yet another dynamical feature - local non-linearity or conformity of the individual to the opinion of its surroundings. This feature appears to have a strong impact both on the way in which an equilibrium state is approached as well as on its characteristics.</p>
ArticlesStatistical PhysicsComputer ModellingComplex Systemscollective decision makingspin modelsbiasconformityP. SarkanychYu. SevinchanM. KrasnytskaP. RomanczukYu. Holovatch
Copyright (c) 2024 P. Sarkanych, Yu. Sevinchan, M. Krasnytska, P. Romanczuk, Yu. Holovatch
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2024-09-242024-09-24338013380110.5488/cmp.27.33801Female representation across mythologies
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/86
<p>Social groups have been studied throughout history to understand how different configurations impact those within them. Along with this came the interest in investigating social groups of both fictional and mythological works. Over the last decade these social groups have been studied through the lens of network science allowing for a new level of comparison between these stories. We use this approach to focus on the attributes of the characters within these networks, specifically looking at their gender. With this we review how the female populations within various narratives and to some extent the societies they are based in are portrayed. Through this we find that although there is not a trend of all narratives of the same origin having similar levels of representation some are noticeably better than others. We also observe which narratives overall prioritise important female characters and which do not.</p>
ArticlesStatistical Physicsnetworkscomplex systemssocial systemsM. JanickyjP. MacCarronY. YoseR. Kenna
Copyright (c) 2024 M. Janickyj, P. MacCarron, Y. Yose, R. Kenna
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2024-09-242024-09-24338023380210.5488/cmp.27.33802Quantifying the role of supernatural entities and the effect of missing data in Irish sagas
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/87
<p>For over a decade, complex networks have been applied to mythological texts in order to quantitatively compare them. This has allowed us to identify similarities between texts in different cultures, as well as to quantify the significance of some heroic characters. Analysing a full mythology of a culture requires gathering data from many individual myths which is time consuming and often impractical. In this work, we attempt to bypass this by analysing the network of characters in a dictionary of mythological characters. We show that the top characters identified by different centrality measures are consistent with central figures in the Irish sagas. Although much of Irish mythology has been lost, we demonstrate that these most central characters are highly robust to a large random removal of edges.</p>
ArticlesStatistical PhysicsComplex Systemscomplex networkssocial networksmythologyP. MacCarron
Copyright (c) 2024 P. MacCarron
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2024-09-242024-09-24338033380310.5488/cmp.27.33803In memoriam: Stefan Sokołowski
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/89
<p>It is our real pain to write this article, remembering years of friendship and scientific collaboration with Stefan Sokołowski, who passed away on the 24th of June 2024. He was a strong man in his faith and convictions, a kind and helpful friend, attentive and open-minded in discussions, creative, profound and sophisticated in understanding the flow of life and science. He left an unforgettable mark on our hearts and personal memories. His way of thinking left an imprint on students, young scientists and co-workers. We accompany all that with warm farewell applause as an appreciation of Stefan’s way and effects throughout his life.</p>
PersonaliaPersonaliaO. PizioA. PatrykiejewC. VegaL. PusztaiJa. IlnytskyiT. PatsahanA. Trokhymchuk
Copyright (c) 2024 O. Pizio, A. Patrykiejew, C. Vega, L. Pusztai, Ja. Ilnytskyi, T. Patsahan, A. Trokhymchuk
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2024-09-242024-09-24370013700110.5488/cmp.27.37001Hamiltonian limited valence model for liquid polyamorphism
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/48
<p>Liquid-liquid phase transitions have been found experimentally or by computer simulations in many compounds such as water, hydrogen, sulfur, phosphorus, carbon, silica, and silicon. Limited valence model implemented via event-driven molecular dynamics algorithm provides a simple generic mechanism for the liquid-liquid phase transitions in all these diverse cases. Here, we introduce a variant of the limited valence model with a well defined Hamiltonian, i.e., a unique algorithm by which the potential energy of the system of particles can be computed solely from the coordinates of the particles and is thus equivalent to a complex multi-body potential. We present several examples of the model which can be used to reproduce liquid--liquid phase transition in systems with maximum valence <em>z</em> = 1 (hydrogen), <em>z</em> = 2 (sulfur) and <em>z</em> = 4 (water), where <em>z</em> is the maximum number of bonds an atom is allowed to have. For <em>z</em> = 1, we find a set of parameters for which the system has a liquid-liquid and an isostructural solid-solid critical points. For <em>z</em> = 4, we find a set of parameters for which the phase diagram resembles that of water with a wide region of negative thermal expansion coefficient (density anomaly) extending into the metastable region of negative pressures. The limited valence model can be modified to forbid not only too large valences but also too low valences. In the case of sulfur, we forbid the formation of monomers, thus restricting the valence v of an atom to be within an interval 1 = <em>v</em><sub>min </sub>≤ <em>v</em> ≤ <em>v</em><sub>max </sub>≡ z = 2.</p>
ArticlesSoft Matterliquid-liquid phase transitionliquid-gas phase transitionsolid-solid transformationsphase diagramsS. V. Buldyrev
Copyright (c) 2024 S. V. Buldyrev
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2024-06-282024-06-28236012360110.5488/cmp.27.23601Vapour-liquid phase behaviour of primitive models of ionic liquids confined in disordered porous media
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/49
<p>We develop a theory for the description of ionic liquids (ILs) confined in a porous medium formed by a matrix of immobile randomly placed uncharged particles. The IL is modelled as an electroneutral mixture of hard-sphere anions and flexible linear chain cations, represented by tangentially bonded hard spheres with the charge located on one of the terminal beads. The theory combines a generalization of the scaled particle theory, Wertheim's thermodynamic perturbation theory, and the associative mean-spherical approximation and allows one to obtain analytical expressions for the pressure and chemical potentials of the matrix-IL system. Using the theory, we calculate the vapour–liquid phase diagrams for two versions of the IL model, i.e., when the cation is modelled as a dimer and as a chain, in a complete association limit. The effects of the matrix confinement and of the non-spherical shape of the cations on the vapour-liquid phase diagrams are studied.</p>
ArticlesSoft Matterionic liquidsdisordered porous mediumchain-like cationsvapour-liquid phase diagramsT. HvozdT. PatsahanYu. KalyuzhnyiO. PatsahanM. Holovko
Copyright (c) 2024 T. Hvozd, T. Patsahan, Yu. Kalyuzhnyi, O. Patsahan, M. Holovko
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2024-06-282024-06-28236022360210.5488/cmp.27.23602Plasmonic effects in rod-like metal-dielectric nanoparticles
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/50
<p>The optical properties of rod-like two-layer nanoparticles are studied using the notions of equivalent prolate spheroid. The calculations are presented for frequency dependencies for polarizability and the absorption and scattering cross-section of prolate spheroids, cylinders, and spherocylinders. The effect of the sizes, the shapes of the nanoparticle and the material of the core and the shell on the location of the maxima of the imaginary part of polarizability and absorption and scattering cross-sections is analysed. The recommendations regarding the shape and size ratio of the nanoparticles for obtaining the maximum value of radiation efficiency are formulated.</p>
ArticlesSolid State Physicspolarizabilityequivalent prolate spheroidfrequency dependenciesabsorption and scattering cross-sectionsrod-like nanoparticlesYa. V. Karandas
Copyright (c) 2024 Ya. V. Karandas
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2024-06-282024-06-28237012370110.5488/cmp.27.23701The local structure, electronic and optical properties of Pb(Mg1/3Nb2/3)O3-PbTiO3: first-principles study
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/51
<p>Pb(Mg<sub>1/3</sub>Nb<sub>2/3</sub>)O<sub>3</sub>-PbTiO<sub>3</sub> perovskite-based crystals attract considerable scientific interest due to their interesting properties and possible use in piezoelectricity and photovoltaics. To understand the local structure and fundamental properties of such materials, in this work, we focused on the study within the density functional theory of structural, electronic, and optical properties of Pb[(Mg<sub>1/3</sub>Nb<sub>2/3</sub>)<sub>0.75</sub>Ti<sub>0.25</sub>]O<sub>3</sub>. Using GGA(PBEsol) approximation for structure optimization gives a good agreement with experimental data. Through the variation in Hubbard <em>U</em> parameters to GGA(PBEsol) functional, we achieve the bandgap for the Pb[(Mg<sub>1/3</sub>Nb<sub>2/3</sub>)<sub>0.75</sub>Ti<sub>0.25</sub>]O<sub>3</sub> which is in good agreement with the experimental results. The study of the bond populations showed that the Mg-O bond demonstrates no covalency, whereas there is a significant Ti-O and Nb-O covalent bonding. Such different bonding characteristics must be responsible for the relaxor properties of Pb[(Mg<sub>1/3</sub>Nb<sub>2/3</sub>)<sub>0.75</sub>Ti<sub>0.25</sub>]O<sub>3</sub> compound. In addition, the investigations of the optical properties of the Pb[(Mg<sub>1/3</sub>Nb<sub>2/3</sub>)<sub>0.75</sub>Ti<sub>0.25</sub>]O<sub>3</sub> by adopting Hubbard <em>U</em> corrections, modifying the error of the GGA approximation, and confirming the electronic analysis, were performed.</p>
ArticlesComputer Modellinglocal structurebandgapdensity of statesoptical propertiesM. KovalenkoO. BovgyraV. KapustianykO. Kozachenko
Copyright (c) 2024 M. Kovalenko, O. Bovgyra, V. Kapustianyk, O. Kozachenko
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2024-06-282024-06-28237022370210.5488/cmp.27.23702Spin-1/2 Ising-Heisenberg distorted diamond chain with antiferromagnetic Ising and ferromagnetic Heisenberg interactions
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/52
<p>The exactly solvable spin-1/2 Ising-Heisenberg distorted diamond chain in the presence of the external magnetic field is investigated for the case of antiferromagnetic Ising and ferromagnetic <em>XXZ</em> Heisenberg interactions. The influence of quantum fluctuations and the distortion on the ground state, magnetic and thermal properties of the model are studied in detail.In particular, it is established that the zero-temperature magnetization curve may involve intermediate plateaus just at zero and 1/3 of the saturation magnetization. It is demonstrated that the temperature dependence of the specific heat reveals up to four distinct peaks at zero magnetic field and up to five distinct peaks at a weak magnetic field. The physical origin of all observed additional peaks of the specific heat has been clarified on the grounds of dominating thermal excitations. We have shown that the quantum fluctuations give rise to an effective geometrical frustration in this chain.</p>
ArticlesSolid State PhysicsIsing-Heisenberg distorted diamond chainground statephase diagramspecific heatB. M. Lisnyi
Copyright (c) 2024 B. M. Lisnyi
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2024-06-282024-06-28237032370310.5488/cmp.27.23703Hexagonal core-shell structure nanowire with high spins of spin-3/2 and spin-5/2
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/53
<p>The magnetic properties and hysteresis loops for the hexagonal Ising nanowire (HIN) with a core-shell structure consisting of mixed spins with the core spin being spin-5/2 and the shell spins being spin-3/2 are studied. The Blume-Capel model is considered by using the mean-field approximation (MFA) based on the Gibbs-Bogoliubov inequality for free energy. The impact of different bilinear interaction parameters (<em>J<sub>cc</sub>, J<sub>ss</sub>, J<sub>cs</sub></em>) between the core, shell, and core and shell spins, respectively, including the crystal (<em>D<sub>c</sub>, D<sub>s</sub></em>) and external magnetic fields (<em>h = h<sub>c</sub> = h<sub>s</sub></em>) at the core and shell sites, are taken into consideration. In order to obtain phase diagrams on various planes, the thermal changes of the net, core, and shell magnetizations are investigated for various values of our system parameters. It is discovered that the model exhibits only second-order phase transitions when <em>h</em> = 0.0 for <em>D</em> greater or equal to zero, first- and second-order phase transitions for <em>h</em> ≠ 0.0 and compensation temperatures for all <em>h</em>.</p>
ArticlesSolid State Physicsmean field theoryBlume-Capel modelhysteresis loopscompensation temperaturemagnetizationmixed-spin systemM. KarimouR. A. YessoufouE. Albayrak
Copyright (c) 2024 M. Karimou, R. A. Yessoufou, E. Albayrak
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2024-06-282024-06-28237042370410.5488/cmp.27.23704Self-assembly behaviour of diblock copolymer-diblock copolymer under oscillating shear field
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/54
<p>The self-assembly behaviour of a diblock copolymer-diblock copolymer mixture under an oscillating shear field is investigated via cell dynamics simulation. The results indicate that the macrophase separation of the composite system is accompanied by the corresponding microphase separation induced by the oscillating shear field. With an increase in the shear frequency, the AB phase changes from a tilted layered structure to a parallel layered structure, and finally to a vertical layered structure. The CD phase transforms from the initial concentric ring into a parallel layer in the ring and then into a parallel layered structure; thus, the system finally forms a layered structure of the AB phase (vertical layer) and CD phase (parallel layer) perpendicular to each other. To verify the phase transition, the dynamic evolution of the domain size at different shear frequencies is analysed. The ordered phase transition with an increase in the oscillating shear field varies when the initial composition ratio of the system is changed. This conclusion provides a valuable guidance for the formation and transformation of ordered structures in experiments.</p>
ArticlesSoft Matterdiblock copolymeroscillating shear fieldself-assemblyY. GuoH. HeX. Fu
Copyright (c) 2024 Y. Guo, H. He, X. Fu
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2024-06-282024-06-28238012380110.5488/cmp.27.23801Molecular dynamics simulations of water-ethanol mixtures. I. Composition trends in thermodynamic properties
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/57
<p>We explored the composition dependence of a rather comprehensive set of properties of liquid water-ethanol mixtures by using the isobaric-isothermal molecular dynamics computer simulations. The united atom non-polarizable model from the TraPPE data basis for the ethanol molecule combined with the TIP4P-2005 and SPC/E water models is considered. We restrict our calculations to atmospheric pressure, 0.1013 MPa, and room temperature, 298.15 K. Composition trends of the behavior of density, excess mixing volume, apparent molar volumes are described. On the other hand, the excess mixing enthalpy and partial molar enthalpies of species are reported. Besides, we explore the coefficient of isobaric thermal expansion, isothermal heat capacity, adiabatic bulk modulus and heat capacity at constant pressure. In addition, the self-diffusion coefficients of species, the static dielectric constant and the surface tension are described. We intend to get insights into peculiarities of mixing of species in the mixture upon changes of ethanol molar fraction. The quality of predictions of the models is critically evaluated by detailed comparisons with experimental results. Then, necessary improvements of the modelling are discussed.</p>
ArticlesComputer Modellingmolecular dynamicswater-ethanol mixturessurface tensiondielectric constantpartial molar volumesD. Benavides BautistaM. AguilarO. Pizio
Copyright (c) 2024 D. Benavides Bautista, M. Aguilar, O. Pizio
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2024-06-282024-06-28232012320110.5488/cmp.27.23201The 70th Birthday of Professor Mykola Lebovka
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/56
<p>Professor Mykola Lebovka, an outstanding Ukrainian scientist in the field of physical chemistry of condensed matter, head of the Laboratory of Physical Chemistry of Disperse Minerals in F. D. Ovcharenko Institute of Biocolloidal Chemistry of National Academy of Sciences of Ukraine, the Editorial Board member of the Condensed Matter Physics journal, turns 70 on May 15, 2024.</p>
PersonaliaPersonalia
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2024-06-282024-06-28270022700210.5488/cmp.27.27002The 75th Birthday of Professor Jurij Kozicki
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/55
<p>Professor Jurij Kozicki (a.k.a. Yurij Kozitsky), a renowned scholar in the field of mathematical backgrounds of statistical physics and dynamical systems, an active member of the Editorial board of the Condensed Matter Physics journal and a member of the Institute for Condensed Matter Physics Supervisory Board, celebrates his 75th Birthday.</p>
PersonaliaPersonalia
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2024-06-282024-06-28270012700110.5488/cmp.27.27001In memory of Ihor Yukhnovskii, the founder and editor-in-chief of the journal ''Condensed Matter Physics'' (1925-2024)
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/46
<p>On March 26, 2024, the prominent Ukrainian scholar, theoretical physicist, and founder of the Lviv school of statistical physics, professor, academician of the National Academy of Sciences of Ukraine Ihor Yukhnovskii, passed away. He lived almost 99 years and his life was filled with many events. He was a soldier during World War II, a scientist and educator, and a public and state figure of the highest level. But above all, he was a scientist. He approached any task as a researcher, from formulating the problem to finding its optimal solution. Analytical thinking and mathematical logic dominated all his activities. At the same time, he remarkably combined scientific pragmatism with unexpected imaginative ideas, which ensured his outstanding achievements both in science and in politics.</p>
EditorialEditorial
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2024-06-282024-06-28200012000110.5488/cmp.27.20001Effects of charge and size on the coadsorption of counterionic colloids in Gibbs monolayers
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/13
<p>This study uses a coarse-grained Monte Carlo algorithm to model and simulate the coadsorption of a binary mixture of counterionic colloids in Gibbs monolayers. These monolayers form at a idealized air-water interface, with one non-soluble species confined at the interface and the second one partially soluble in the aqueous phase. The investigation focuses on the effect of colloidal size and charge on the thermodynamics and microstructure of the monolayer. We find that the composition of the monolayer evolves non-trivially with surface coverage, depending on the balance of steric and electrostatic forces. When the electrostatic interactions are weak, the soluble species is expelled from the monolayer upon compression, yielding a phase behaviour particularly sensitive to the relative size of the soluble and non-soluble colloids. By contrast, strong electrostatic interactions favour the stabilization of the soluble particles in the monolayer and the formation of quasi-equimolar fluids, with only a weak dependence on particle size. The combination of these phenomena results in the formation of a number of two-dimensional mesoscopic arrangements in the monolayer, ranging from diluted gas-phase behaviour to domains of aggregates and percolates, and to incipient crystalline structures.</p>
ArticlesSoft MatterGibbs monolayersMonte Carloequations of stateaggregationJ. M. Gómez-VerdúB. Martínez-HayaA. Cuetos
Copyright (c) 2024 J. M. Gómez-Verdú, B. Martínez-Haya, A. Cuetos
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2024-03-282024-03-28136011360110.5488/cmp.27.13601Description of CuInP2S6 ferrielectrics in a mixed Ising model
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/44
<p>The appearance of spontaneous polarization in CuInP<sub>2</sub>S<sub>6</sub> ferrielectrics is related to the second order Jahn-Teller effect for copper cations located in a double-well local potential, the stereoactivity of indium cations located in a three-well local potential, as well as the valence fluctuations of phosphorus cations. The paraelectric to ferrielectric phase transition is primarily determined by the coupling of indium cations with their surroundings. This transition can be analyzed using the mixed Ising model with spins <em>s</em> = 1/2 and <em>S</em> = 1. The spectrum of pseudospin fluctuations at different temperatures was calculated using a mean-field approach for a set of quantum anharmonic oscillators. The results were then compared with Raman spectroscopy data for CuInP<sub>2</sub>S<sub>6</sub> crystal. The analysis indicates that the lattice anharmonicity below 150 K, is mainly determined by the indium sublattice, leading to the coexistence of the glassy state and ferrielectric phase. Above 150 K, the anharmonicity of the copper sublattice activates the ionic conductivity and results in the existence of a long-ranged fluctuated cluster of spontaneous polarization in a temperature interval of the paraelectric phase above <em>T<sub>C</sub></em>.</p>
Rapid CommunicationSolid State PhysicsferrielectricsCuInP2S6mixed Ising modelquantum anharmonic oscillator modelR. YevychV. LiubachkoV. HrytsM. MedulychA. KohutychYu. Vysochanskii
Copyright (c) 2024 R. Yevych, V. Liubachko, V. Hryts, M. Medulych, A. Kohutych, Yu. Vysochanskii
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2024-03-282024-03-28147011470110.5488/cmp.27.14701Computer simulations of soft matter. On 60-th anniversary of Jaroslav Ilnytskyi
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/43
<p>This special issue Condensed Matter Physics, entitled "Computer Simulations of Soft Matter" is dedicated to Jaroslav Ilnytskyi on the occasion of his 60-th birthday. Prof. J. Ilnytskyi is one of scientific leaders of the Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine (NASU), who iswell known for his contributions to the theory and computer simulation studies of polymer fluids, liquid crystals, macromolecular and colloid solutions. Versatility of Jaroslav works is due to his excellent background commonly resulting in original ideas, his feeling and ability to choose and apply appropriate methods for the solution of various problems. Finally, Jaroslav works are distinguished by the profound analyses of either theoretical or simulation results with respect to experimental observations frequently complemented by the discussion of possible applications.</p>
EditorialEditorialO. PizioT. PatsahanV. Blavatska
Copyright (c) 2024 O. Pizio, T. Patsahan, V. Blavatska
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2024-03-282024-03-28101011010110.5488/cmp.27.10101Finite size effects and optimization of the calculation of the surface tension in surfactant mixtures at liquid/vapour interfaces
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/41
<p>The surface tension of monolayers with mixtures of anionic and nonionic surfactant at the liquid/vapour interface is studied. Previous works have observed that calculations of the surface tension of simple fluids show artificial oscillations for small interfacial areas, indicating that the surface tension data fluctuate due to the finite size effects and periodic boundary conditions. In the case of simulations of monolayers composed of surfactant mixtures, the surface tension not only oscillates for small areas but can also give non-physical data, such as negative values. Analysis of the monolayers with different surfactant mixtures, ionic (DTAB, CTAB, SDS) and nonionic (SB3-12), was done for density profiles, parameters of order and pair correlation functions for small and large box areas and all of them present similar behaviour. The fluctuations and the non-physical values of the surface tension are corrected when boxes with large interfacial areas are considered. The results indicate that in order to obtain reliable values of the surface tension, in computer simulations, it is important to choose not only the correct force field but also the appropriate size of the simulation box.</p>
ArticlesSoft Matterfinite size effectsmolecular dynamicssurface tensionsurfactant monolayer mixtureswater/airC. J. Guzman-ValenciaJ. Toriz-SalinasH. Espinosa-JimenezA. B. Salazar-ArriagaJ. L. López-CervantesH. Dominguez
Copyright (c) 2024 C. J. Guzman-Valencia, J. Toriz-Salinas, H. Espinosa-Jimenez, A. B. Salazar-Arriaga, J. L. López-Cervantes, H. Dominguez
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2024-03-282024-03-28136051360510.5488/cmp.27.13605Dimerizing hard spherocylinders in porous media
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/39
<p>This research focuses on the unique phase behavior of non-spherical patchy colloids in porous environments. Based on the theory of scaled particle (SPT), methods have been refined and applied to analyze the thermodynamic properties of non-spherical patchy particles in a disordered porous medium. Utilizing the associative theory of liquids in conjunction with SPT, we investigated the impact of associative interactions and connections between the functional nodes of particles on the formation of the nematic phase. Calculations of orientational and spatial distributions were conducted, which helped to understand the phase behavior of particles during the transition from isotropic to nematic phase under the spatial constraints imposed by the disordered matrix of the porous medium.</p>
ArticlesSoft Matterpatchy colloidsspherocylindersdimerizationdisordered porous mediageometrical porosityprobe particle porosityV. I. ShmotolokhaM. F. Holovko
Copyright (c) 2024 V. I. Shmotolokha, M. F. Holovko
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2024-03-282024-03-28136071360710.5488/cmp.27.13607When correlations exceed system size: ﬁnite-size scaling in free boundary conditions above the upper critical dimension
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/37
<p>We progress finite-size scaling in systems with free boundary conditions above their upper critical dimension, where in the thermodynamic limit critical scaling is described by mean-field theory. Recent works show that the correlation length is not bound by the system's physical size, a belief that long held sway. Instead, two scaling regimes can be observed — at the critical and pseudo-critical temperatures. We demonstrate that both are manifest for free boundaries. We use numerical simulations of the <em>d</em> = 5 Ising model to analyse the magnetization, susceptibility, magnetization Fourier modes and the partition function zeros. While some of the response functions hide the dual finite-size scaling, the precision enabled by the analysis of Lee–Yang zeros allows this be brought to the fore. In particular, finite-size scaling of leading zeros at the pseudo-critical point confirms recent predictions coming from correlations exceeding the system size. This paper is dedicated to Jaroslav Ilnytskyi on the occasion of his 60th birthday.</p>
ArticlesStatistical Physicsuniversalityﬁnite-size scalingupper critical dimensionYu. HoncharB. BercheYu. HolovatchR. Kenna
Copyright (c) 2024 Yu. Honchar, B. Berche, Yu. Holovatch, R. Kenna
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2024-03-282024-03-28136031360310.5488/cmp.27.13603Universal properties of branched copolymers in dilute solutions
https://cmpj2.icmp.lviv.ua/index.php/cmpj/article/view/26
<p>We analyze the universal conformational properties of complex copolymer macromolecules, based on two topologies: the <em>rosette</em> structure containing f<sub>c</sub> linear branches and f<sub>r</sub> closed loops grafted to the central core, and the symmetric <em>pom-pom</em> structure, consisting of a backbone linear chain terminated by two branching points with functionalities <em>f</em>. We assume that the constituent strands (branches) of these structures can be of two different chemical species <em>a</em> and <em>b</em>. Depending on the solvent conditions, the inter- or intrachain interactions of some links may vanish, which corresponds to Θ-state of the corresponding polymer species. Applying both the analytical approach within the frames of direct polymer renormalization and numerical simulations based on the lattice model of polymer, we evaluated the set of parameters characterizing the size properties of constituent parts of two complex topologies and estimated quantitatively the impact of interactions between constituent parts on these size characteristics.</p>
ArticlesStatistical PhysicsSoft Matterpolymersscalinguniversal propertiesrenormalization groupnumerical simulationsK. HaydukivskaV. Blavatska
Copyright (c) 2024 K. Haydukivska, V. Blavatska
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2024-03-282024-03-28133011330110.5488/cmp.27.13301