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Computational Chemistry 2024年第2期12卷 25-56页

作者： Krzysztof Wojciechowski lucjan szuster Institute of Environmental Engineering and Building Installations Lodz University of Technology d Poland Institute of Leather Industry d Poland

We analysed the photooxidation reaction in the electro-(1O2) and nucleophilic (O2•−) reaction of 2-pyridone azo derivatives. First, we calculated the energy (enthalpies) of tautomers formation, which is a measure of durability and the probability of their formation. We performed the light fastness calculations of the monoazopyridone dyes. Using the semi-empirical methods of quantum chemistry AM1 and PM3, the reactivity indicators of superdelocalisability (SrE(N)) and the electron density distribution in ground state on the highest occupied HOMO orbital and the lowest unoccupied excited state LUMO in 2-pyridone phenylazo derivatives were calculated. Superdelocalisability coefficients enable the stability to oxidising agents of various chemical molecules depending on the tautomeric forms in which they may occur. The results of the electron density calculations at the HOMO and LUMO boundary orbitals allow to determine the tendency to electrophilic attack with singlet oxygen 1O2 or nucleophilic attack of the superoxide anion O2•−on a specific atom in the molecule. The structure of the dyes was optimised with MM+, MD and AM1 or PM3 until a constant energy value was achieved with a convergence criterion of 0.01 kcal/mol.

关键词： Photochemical Degradation AM1 and PM3 Methods Boundary Orbitals Electron Densities Electrophilic and Nucleophilic Reaction HOMO and LUMO Orbitals

[Azo-Hyd] Tautomerism and Structure of Selected Metal Complex Dyes AM1 and ZINDO/1 Methods

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Computational Chemistry 2016年第4期4卷 97-118页

作者： Krzysztof Wojciechowski lucjan szuster Institute of Environmental Engineering and Building Installations Technical University of Lód&zacute Lód&zacute Poland Leather Research Institute Lód&zacute Poland

Quantum-chemical calculation methods have been used to examine an influence of tautomeric equilibrium [Azo Hydrazo] on a structure of 1:2 chromium metal complex dyes called Gryfalan Navy Blue RL (CI 15 707, Acid Blue 193) and Gryfalan Black RL (Acid Black 194). Chromatographic analysis indicates that synthesis yields a mixture of several dyes with different shades. Studies conducted to date have suggested that such dye complexes can constitute Drew-Pfitzner or Pfeiffer-Schetty structural isomers [1]. It is a know fact, that o-hydroxy-azo dyes exist in equilibrium of tautomeric azo and hydrazone forms. We decided to examine, whether color properties of examined metal-complex dyes can be influenced also by an azo-hydrazone equilibrium and what kind of influence on it has sulphonic groups present in molecules. Calculation and optimization of the geometrical structure were performed using the AM1 methods for monoazoo-hydroxy-azo dyesand ZINDO/1 for 1:2 chromium metal complex dyes. It was stated that monoazo dyes can create complexes in both forms: azo and hydrazone, because energy differences between each form of the metal complex dye are so small, that the monoazo dye can, in practice, create complexes in both the azo and the hydrazone form, with energy differences not exceeding about 4 - 11 kcal/mol. It is calculated that spatial structure changes with an angle of about 90° between two molecules of the dye, and angles of 10° - 20° between the naphthalene moieties. Similar electron density on the hydroxyl and ketone groups suggests that the mixture contains a dominant share of the azo form. The presence of an ionised sulphonic group was also found to affect on the tautomer equilibrium.

关键词： Acid Dyes Cr Metal Complexes Quantum-Chemical Calculations AM1 and ZINDO/1 Methods

Photofading of Derivatives of Paraben (PHB) by AM1 and PM3 Methods: A Theoretical Study

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Computational Chemistry 2019年第2期7卷 39-50页

作者： Krzysztof Wojciechowski lucjan szuster Institute of Environmental Engineering and Building Installations Technical University of &#321 ódź ódź Poland Leather Research Institute &#321 ódź Poland

Calculations of chemical structures and photofading of parabens (PHB—4 hydroxybenzoic acid), which are p-hydroxybenzoic acid alkyl esters were performed. These compounds are used as preservatives for the substances used in cosmetics. The reactivity of these derivatives with an oxidant—singlet oxygen—have been tested with a theoretical method of frontier orbitals. All-valence molecular orbital methods, AM1 and PM3, have been used to calculate frontier electron density for higher occupied HOMO and lower unoccupied LUMO orbitals, which might be sensitive to an electrophilic (with singleton oxygen atom 1O2) or nucleophilic ( superoxide anion radical) attack at a particular atom in a molecule. Using AM1 and PM3, we calculated the reactivity , superdelocalisability and electron density distributions. The obtained superdelocalisability rates allow you to explain the fastness values in different chemical molecules. The structure of parabens (PHB) was optimized by MM+, DM, AM1 or PM3, to achieve constant energy values at a convergence criterion of 0.01 kcal/mol. The performed calculations indicate that the electrophilic oxidation reaction should take place in the aromatic ring in the 2-position to the hydroxyl residue of PHB, whereas the superoxide radical reaction occurs mainly on the alkyl residues of the ester group. The reaction may take place according to superoxide mechanism or 1,2-addition, where the higher superdelocalisability values SN are located on neighboring atoms in aromatic systems.

关键词： Photofading of Parabens All-Valence MO Calculation Orbital Frontier Electron Density Electrophilic and Nucleophilic Attack Theoretical Study

Can electrons attract one another?

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Science China Chemistry 2014年第10期57卷 1383-1392页

作者： PIELA lucjan Quantum Chemistry Laboratory University of Warsaw

Electrons are believed to avoid one another in space(correlation) due to the Coulomb repulsion and/or the Pauli exclusion *** is shown, using examples of two-electron systems, that indeed the mean electron-electron distance increases in case of the ground electronic state as compared to the independent electron model. It is demonstrated however that there exist excited states, often of low energy, in which the electrons, while having a lot of free physical space(with nuclei being absent), choose to be close to each other in their motion("anticorrelation"), as if they mutually attracted one another. The source of this effect, quantummechanical in nature, is the orthogonality of the eigenfunctions, that forces the electronic wave functions to differ widely, even at the price of short electron-electron distances. There are also excited states with a mixed behaviour, with complex and often intriguing correlation-anticorrelation patterns.

关键词： electron-electron attraction electron anticorrelation electron correlation electron-electron distance electron pair electron pair emission Cooper pairs Coulomb hole Fermi hole super conductivity

Applications of the conformal transformation method instudies of composed superconducting systems

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Frontiers of physics 2016年第6期11卷 109-127页

作者： Mateusz Krzyzosiak Ryszard Gonczarek Adam Gonczarek lucjan Jacak University of Michigan-Shanghai Jiao Tong University Joint Institute 800 Dongchuan Rd. Shanghai 200240 China Faculty of Fundamental Problems of Technology Wroctaw University of Technology Wybrzeze Wyspianskiego 27 50-370 Wroctaw Poland Faculty of Computer Science and Management Wroctaw University of Technology Wybrzeze Wyspianskiego 27 50-370 Wroc~aw Poland

A framework for analytical studies of superconducting systems is presented and illustrated. The formalism, based on the conformal transformation of momentum space, allows one to study the effects of both the dispersion relation and the structure of the pairing interaction in two-dimensional anisotropic high-T c superconductors. In this method, the number of employed degrees of freedom coincides with the dimension of the momentum space, which is different compared to that in the standard Van Hove scenario with a single degree of freedom. A new function, the kernel of the density of states, is defined and its relation to the standard density of states is explained. The versatility of the method is illustrated by analyzing coexistence and competition between spin-singlet and spin-triplet order parameters in superconducting systems with a tight-binding-type dispersion relation and an anisotropic pairing potential. Phase diagrams of stable superconducting states in the coordinates ?· (the ratio of hopping parameters) and n (the carrier concentration) are presented and discussed. Moreover, the role of attractive and repulsive on-site interactions for the stability of the s-wave order parameter is explained.

关键词： high-temperature superconductivity conformal transformation pairing symmetry critical temperature 74.20.Rp 74.25.Dw 74.62.Yb 74.20.Fg

Analytical assessment of some characteristic ratios for s-wave superconductors

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Frontiers of physics 2018年第2期13卷 201-212页

作者： Ryszard Gonczarek Mateusz Krzyzosiak Adam Gonczarek lucjan Jacak Faculty of Fundamental Problems of Technology Wroctaw University of Technology Wybrzeze Wyspianskiego 27 50-370 Wroctaw Poland University of Michigan-Shanghai Jiao Tong University Joint Institute 800 Dongchuan Road Shanghai 200240 China Faculty of Computer Science and Management Wroctaw University of Technology Wybrzeze Wyspianskiego 27 50-370 Wroctaw Poland

We evaluate some thermodynamic quantities and characteristic ratios that describe low- and high- temperature s-wave superconducting systems. Based on a set of fundamental equations derived within the conformal transformation method, a simple model is proposed and studied analytically. After including a one-parameter class of fluctuations in the density of states, the mathematical structure of the s-wave superconducting gap, the free energy difference, and the specific heat difference is found and discussed in an analytic manner. Both the zero-temperature limit T = 0 and the subcritical temperature range T ≤ Tc are discussed using the method of successive approximations. The equation for the ratio R1, relating the zero-temperature energy gap and the critical temperature, is formulated and solved numerically for various values of the model parameter. Other thermodynamic quantities are analyzed, including a characteristic ratio R2, quantifying the dynamics of the specific heat jump at the critical temperature. It is shown that the obtained model results coincide with experimental data for low-To superconductors. The prospect of application of the presented model in studies of high-To superconductors and other superconducting systems of the new generation is also discussed.

关键词： superconductivity characteristic ratios fluctuation of the DoS

A Mathematical Model and Simulations of Low Temperature Nitriding Katarzyna Tkacz-Smiech *** dedicate this article to the memory of Professor Katarzyna Tkacz-Smiech

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 777-803页

作者： Bogusław Bo˙zek lucjan Sapa Katarzyna Tkacz-Smiech Marek Danielewski Janusz Rybak AGH University of Science and Technology Faculty of Applied MathematicsCracow30-059Poland AGH University of Science and Technology Faculty of Materials Science and CeramicsCracow30-059Poland

Low-temperature nitriding of steel or iron can produce an expanded austenite phase,which is a solid solution of a large amount of nitrogen dissolved interstitially in fcc *** is characteristic that the nitogen depth profiles in expanded austenite exhibit plateau-type *** behavior cannot be considered with a standard analytic solution for diffusion in a semi-infinite solid and a new approach is *** formulate a model of interdiffusion in viscoelastic solid(Maxwellmodel)during the nitriding *** combines themass conservation and Vegard’s rule with the Darken bi-velocity *** model is formulated in any dimension,i.e.,a mixture is included in R^(n),n=1,2,*** the system in one dimension,n=1,we transform a differential-algebraic system of 5 equations to a differential system of 2 equations only,which is better to study numerically and *** modification allows the formulation of effective mixed-type boundary *** resulting nonlinear strongly coupled parabolic-elliptic differential initial-boundary Stefan type problem is solved numerically and a series of simulations is made.

关键词： Nitriding expanded austenite Maxwell solid Darken method Vegard rule

How minor structural changes generate major consequences in photophysical properties of RE coordination compounds;resonance effect,LMCT state

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Journal of Rare Earths 2020年第5期38卷 552-563页

作者： Ewa Kasprzycka Albano N.Carneiro Neto Viktor A.Trush lucjan Jerzykiewicz Vladimir M.Amirkhanov Oscar L.Malta Janina Legendziewicz Paula Gawryszewska University of Applied Sciences-Fachhochschule Münster Department of ChemicalEngineeringStegerwaldstr.39Steinjurt48565Germany Physics Department and CICECO-Aveiro Institute of Materials University of Aveiro38 JO-193AveiroPortugal Department o f Chemistry Taras Shevchenko National University of Kyivul.Volodymyrska 64Kyiv01601 Ukraine Faculty of Chemistry University of Wroclaw14 F.Joliot-Curie Street50-383WroclawPoland Departamento de Quimica Fundamental Universidade Federal de Pernambuco Cidade Universitaria RecifePE50740-560Brazil

Lanthanide coordination compounds of the formula Na[Ln(L)4](1 Ln),where Ln=La^3+,Eu^3+,Gd^3+,Tb^3+,L=[L]-and HL=dimethyl(4-methylphenylsulfo nyl)amidophosphate,were *** structural and spectro scopic properties were discussed in detail based on X-ray diffraction measurements,IR spectroscopy,absorption and emission spectroscopy at 293 and 77 K and theoretical calculations of the intramolecular energy transfer(IET)*** calculations were used to investigate the 1 Ln electronic properties re quired to calculate the transition rates.30 and 22 pathways of intramolecular nonradiative energy transfer were examined in the case of 1 Eu and 1 Tb,*** is shown that the main pathway for sensitization of the lanthanide emission is either the triplet(1 Eu)or singlet(1 Tb)transfer,occurring mainly through the exchange *** energy rates for energy transfer from S1 and T1 equal WS=1.53×10^5 s^-1(1 Eu),WT=5.14×10^6 s^-1(1 Eu)and WS=4.09×10^7 s^-1(1 Tb),WT=6.88×10^5 s^-1(1 Tb).The crucial role of the 7 F5 level in the energy transfer process of 1 Tb and the participation of the LMCT state in the depopulation of the ligand singlet state of 1 Eu were *** influence of the resonance effect on the splitting of the7 F1 level in 1 Eu was *** comparing the properties of 1 Ln with the properties of 2 Ln coordination compounds,sharing the same ligand and crystallizing in the same crystallographic system(monoclinic),but with a different space group,it is demonstrated how slight structural changes can affect the photophysical properties of Ln compounds.

关键词： Lanthanide Phosphorylated sulfonamides Energy transfer Antenna effect Crystal structure Resonance effect

The Triggering Role of Carrier Mobility in the Fractional Quantum Hall Effect Formation—An Evidence in Graphene

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Journal of Modern Physics 2013年第12期4卷 1591-1596页

作者： Janusz Jacak lucjan Jacak Institute of Physics Wroclaw University of TechnologyWroclawPoland

Recent experiments with suspended graphene have indicated the crucial role of carrier mobility in the competition between Laughlin collective state and insulating state, probably of Wigner-crystal-type. Moreover, the fractional quantum Hall effect (FQHE) in graphene has been observed at a low carrier density where the interaction is reduced as a result of particles dilution. This suggests that the interaction may not be a sole factor in the triggering of FQHE as it was expected basing on the standard formulation of the composite fermion model. Here, the topological arguments are presented to explain the observed features of the FQHE in graphene and the triggering role of carrier mobility in formation of the Laughlin state.

关键词： Graphene FQHE Braid Groups Composite Fermions

Homotopy Approach to Fractional Quantum Hall Effect

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Applied Mathematics 2015年第2期6卷 345-358页

作者： Janusz Jacak Patrycja Lydzba lucjan Jacak Institute of Physics Wroclaw University of TechnologyWroclawPoland

The topology-based explanation of the origin of the fractional quantum Hall effect is summarized. The cyclotron braid subgroups crucial for this approach are introduced in order to identify the origin of Laughlin correlations in 2D Hall systems. The so-called composite fermions are explained in terms of the homotopy cyclotron braids. Some new concept for fractional Chern insulator states is formulated in terms of the homotopy condition applied to the Berry field flux quantization.

关键词： Quantum Hall Effects Braid Groups Homotopy Methods