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1

Do we still need a laboratory to study advanced oxidation processes? A review of the modelling of radical reactions used for water treatment

Wacławek Stanisław

Ecological Chemistry and Engineering. S

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2021

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Vol. 28, nr 1

11--28

EN

Environmental pollution due to humankind’s often irresponsible actions has become a serious concern in the last few decades. Numerous contaminants are anthropogenically produced and are being transformed in ecological systems, which creates pollutants with unknown chemical properties and toxicity. Such chemical pathways are usually examined in the laboratory, where hours are often needed to perform proper kinetic experiments and analytical procedures. Due to increased computing power, it becomes easier to use quantum chemistry computation approaches (QCC) for predicting reaction pathways, kinetics, and regioselectivity. This review paper presents QCC for describing the oxidative degradation of contaminants by advanced oxidation processes (AOP, i.e., techniques utilizing •OH for degradation of pollutants). Regioselectivity was discussed based on the Acid Blue 129 compound. Moreover, the forecasting of the mechanism of hydroxyl radical reaction with organic pollutants and the techniques of prediction of degradation kinetics was discussed. The reactions of •OH in various aqueous systems (explicit and implicit solvation) with water matrix constituents were reviewed. For example, possible singlet oxygen formation routes in the AOP systems were proposed. Furthermore, quantum chemical computation was shown to be an excellent tool for solving the controversies present in the field of environmental chemistry, such as the Fenton reaction debate [main species were determined to be: •OH < pH = 2.2 < oxoiron(IV)]. An ongoing discussion on such processes concerning similar reactions, e.g., associated with sulphate radical-based advanced oxidation processes (SR-AOP), could, in the future, be enriched by similar means. It can be concluded that, with the rapid growth of computational power, QCC can replace most of the experimental investigations related to the pollutant’s remediation in the future; at the same time, experiments could be pushed aside for quality assessment only.

2

Tert-butyl esters of 2,3-diaryl-3-arylaminopropanoic acids – stereoselective synthesis, isolation, spectroscopic and structural elucidation

Tasheva D. N., Zareva S. Y.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 3

12-17

EN

A series of seven substituted tert-butyl esters of 2,3-diaryl-3-arylaminopropanoic acids has been synthesized, isolated, spectroscopically and structurally elucidated. An influence of the substituents on the spectroscopic characteristics and conformations is discussed using the data of the linear-polarized IR- (IR-LD), UV-spectroscopy and 1H-NMR. Theoretical quantum chemical calculations are carried out, with a view to explaining and supporting the experimental optical properties and the electronic structure. The stereoselective synthesis of the corresponding diastereoisomers is optimized, thus giving good yields (62–72%) and purity of the compounds.

3

Methods of theoretical description of molecular materials

Eilmes A.

Scientific Bulletin. Physics / Lodz University of Technology

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2006

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Vol. 26

13-19

EN

A review of some recent results in theoretical modeling of molecular materials is presented. Particular attention is paid to the possibility of developing complex models combining various theoretical approaches.

PL

w pracy omówiono podstawowe metody teoretyfcznego opisu/modelowania układów molekularnych: oblicznia ab initio, mechanika i dynamika molekularna, metody Monte Carlo. Przedstawiono przegląd najpopularniejszych programów i pakietów obliczeniowych. Zastosowanie metod obliczeniowych a takża potencjalne źródła problemów, jakie mogą się z nimi wiązać, zilustrowane zostały przykładami zaczerpniętymi z literatury (np. badania oligoacenów, modelowanie kryształów molekularnych) i z prac wykonywanych ostatnio w Zespole Półprzewodników Organicznych Wydziału Chemii UJ (np. parametryzacja oddziaływań międzycząsteczkowych i pól siłowych, modelowanie transportu jonów w stałym elektrolicie polimerowym).

4

Idee chemii kwantowej [rec.]

Konarski J.

Postępy Fizyki

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2004

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T. 55, z. 5

234-235

PL

Recenzja książki: Lucjan Piela - Idee chemii kwantowej, Wydawnictwo Naukowe PWN, Warszawa 2003, s. 1137.

5

Ab initio study of urea crystal

Xue D., Ratajczak H.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 3-4

143-154

EN

Dielectric properties - linear (refractive indices) and nonlinear optical responses - of urea crystal are quantitatively calculated using static ab initio quantum chemistry calculations at the self-consistent field (SCF) level of theory. The polarizabili-ties and first hyperpolarizabilities of the urea molecule are used to calculate macroscopic susceptibilities of the urea crystal. The calculated values of the urea crystal can agree well with experimental data and other reports. The effect of hydrogen bonds on the susceptibilities of the urea crystal may be neglected. The present work provides us a useful way to deal with quantum chemistry calculations of such molecular crystals as urea.

6

Kwantowochemiczne metody prognozowania selektywności [2 + 3] cykloaddycji

Jasiński Radomir, Markowska Agnieszka, Barański Andrzej

Wiadomości Chemiczne

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2002

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[Z] 56, 1-2

9--38

EN

In general, quantum-chemical methods for prediction of the outcome of cycloaddition reactions can be classified into three groups, depending on the particular reaction steps. The least used first group comprises the reactivity indexes, which are based on the analysis of stationary states of substrates. The second group contains the indirect methods of determination of activation energy, such as PMO, FMO and BL. The third group includes the methods relying on finding and characterization of critical structures on the corresponding potential energy hypersurface. BL and PMO methods can be applied only for the reactions that obey the principle of non-intercrossing of the energy profiles. These methods are mutually complementary and are used for description of different reaction stages of [2+3] cycloadditions. In the case of a late transition state, the activation energy is controlled primarily by the electronic effects related to formation of new bonds, rather than by the weak donor-acceptor interactions of substrates that are the basis for PMO and FMO methods. Reverse situation occurs when the activation barrier is controlled by an early transition state whose structure resembles substrates. Despite some reported successes, BL method has not become so popular as PMO. This results probably from the narrower scope of potential applications of the former method compared to the later one as well as from the BL method formalism. BL is used for explanation of specific aspects of [2+3] cycloadditions rather than for the reactivity predictions in the literal sense. Availability of fast computers and advanced quantum-chemical software has caused the [2+3] cycloaddition analysis based on localization and characterization of critical points on the potential energy hypersurface has gained popularity in recent years. Such analysis affords information about reactivity of the reagents, reaction mechanism, and, regio-, stereo- and periselectivity of practically any kind of reactions. By this method, transition state geometry and its physicochemical parameters, such as charge distribution, ionization potential, or dipole moment, can be determined. The transition state dipole moment can be used for prediction of the reaction course in solvents of different polarity. Moreover, there are procedures for direct calculations in the presence of a simulated dielectric medium, such as a solvent.

7

Modelowanie oddziaływania wodoru z metalami przejściowymi za pomocą teorii funkcjonałów gęstości (DFT). Perspektywa kwantowych modeli katalizy heterogenicznej

Bartczak W.M., Romanowski S., Łandwijt M.

Wiadomości Chemiczne

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2001

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[Z] 55, 7-8

629-655

EN

Computer modelling of catalytic effects of a series of the transition metals and their alloys on the process of dissociation of molecular hydrogen has been performed. The project was composed of three stages. First, the binding energy versus the internuclear distance has been calculated for a series of metal dimers and mixed dimers: Ni2, NiCu, Cu2, Ag2, AgPd, Pd2 Au2, Pt2, AuPt. It has been shown that the traditional methods of quantum chemistry: the ZINDO semiempirical methods and the Hartree-Fock methods do not work properly in the case of the transition metal dimers. In contrast with these methods, the calculations based on the nonlocal version of the density functional theory (DFT) provide very good results, in full agreement with available experimental data concerning the dissociation energies and equilibrium bond lengths of the metal dimers. Then, using the fitted Morse form of the potential interaction between the metal atoms, the Molecular Dynamics (MD) simulations have been performed in order to obtain the atomic structures appearing in the alloys. The third part of the project includes the quantum-chemical calculations of hydrogen atom and hydrogen molecule positioned over the metallic dimers. The interatomic distances of the dimers were taken from the MD calculations. A range of the distances of hydrogen from the metal dimers was scanned. The evolution of energy and electron density with the hydrogen distance from certain dimers, like NiCu, AgPd and Pd2, clearly exhibits the process of the hydrogen molecule dissociation. On a basis of these calculations a measure of catalytic power of the metals was defined and the series of metals and alloys was ordered according to their catalytic power. It was found that the highest catalytic power with respect to the hydrogen dissociation process is exhibited by NiCu alloys. All the quantum-chemical calculations have been performed using the methods of the Density Functional Theory. The nonlocal version of the DFT was applied with the gradient-corrected hybrid functionals for electron exchange and correlation. The GAUSSIAN 98 suite of programs was employed in the calculations.

8

Quantum chemical studies of Cl-...HNO comlex in the singlet and triplet electronic states

Latajka Z., Ratajczak H.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 2

125-131

EN

The structure and energetics of the hydrogen bonded complex formed between HNO and Cl- in the singlet and triplet states was investigated at the MP2 level with 6-31+ G(d, p) basis set. It is shown that the complex is strongly bound. The binding energy of the complex calculated at the MP4(SDTQ)/6-311++ G(2d,2p) level is -15.42 kcal/mol for the singlet state and —25.75 kcal/mol for the triplet state.

9

Modelowe obliczenia kwantowomechaniczne w chemii

Abildgaard J., Hansen P.E.

Wiadomości Chemiczne

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2000

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[Z] 54, 9-10

845-887

EN

The paper reviews quantum chemical methods, ab initio as well as semiempirical methods based on the investigated molecules, salicylaldehede. The discussion is focused on determination of structure, calculation of vibrational frequencies, NMR chemical shifts and isotope effect on the latter. The various schemes, restricted Hartree-Fock (RHF), RHF including second order electron correlation and a series of old and new density functional theory (DFT) methods are compared with well known semiempirical methods like AM1, PM3, CNDO, etc. Add to this the multitude of basis sets. The comparisons are made with respect to time and space requirements, convergence and quality of results. A goal of the present paper is to find a molecular orbital method that in general will calculate both geometries and spectroslopic data as well.

10

Quantum chemical verification of new paramagnetic Mo(V) centre in MnO3

Brocławik E., Łabanowska M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 4

303-311

EN

The aim of our work was independent verification of the proposed from EPR experiment uncommon nature of paramagnetic Mo(V) species lacking molybdenyl oxygene For this purpose quantum chemical DFT calculations have been carried out for [MoO(5)H8](3+) cluster model of reduced MOO3. Good agreement between the energy level diagram elucidated from EPR data with calculated orbital energies led to the conclusion that the structure of this Mo(V) centre seems to be well founded.

11

Fizyka molekularna z elementami chemii kwantowej [rec.]

Balter A.

Postępy Fizyki

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1999

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T. 50, z. 6

327-327

PL

Recenzja książki: Hermann Haken, Hans Christoph Wolf - Fizyka molekularna z elementami chemii kwantowej, z jęz. angielskiego przełożyli Irena Deperasińska i Jerzy Prochorow, Wydawnictwo Naukowe PWN, Warszawa 1998, s. 521 (tytuł dotowany przez Ministra Edukacji Narodowej).