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Thermochemical Properties of High Nitrogen Energetic Materials
Bartošková, Monika ; Munzarová, Markéta (referee) ; Potáček, Milan (referee) ; Jalový,, Zdeněk (referee) ; Vávrová, Milada (advisor)
The main goal of the presented thesis is a theoretical study of heat of formation for high-nitrogen energetic materials. A modification of the classical approach to the isodesmic reactions is realized with the intent that molecules on both sides of the corresponding equation have not only the same number of atoms but also approximately the same size and skeletal similarity. This approach is designated as a method "Alternative Isodesmic Reaction (AIR method)". At its base, using the DFT B3LYP / cc-pVTZ and B3PW91 / cc-pVTZ, for the high nitrogen heterocycles, which are selected from the group of triazoles, triazines, tetrazines, the enthalpy of formation values the gaseous phase f H°(298,g), were obtained whose values are close to the published f H°(298,g). Their application in the calculation of the relevant characteristics of these heterocycles detonation gave real values.
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Development of new methodology for accurate determination of molecular geometry
Socha, Ondřej ; Dračínský, Martin (advisor) ; Munzarová, Markéta (referee) ; Hrabal, Richard (referee)
This thesis employs the combined strengths of Nuclear Magnetic Resonance (NMR) and computational methodologies to investigate chemical phenomena that influence molec- ular structure across the solid, liquid, and gas states. In the solid phase, the research focuses on chlorine quadrupole couplings, and their use in structure analysis, highlight- ing the advantages of NMR in conjunction with Density Functional Theory for data interpretation. In the liquid state, the tautomeric conversion of isocytosine is examined, underlining the role of NMR in analyzing intricate chemical exchanges. The gas phase study explores the dimerization of acetic acid using NMR, addressing previous inconsis- tencies and evaluating calculations of molecular structure and properties. The combined use of NMR and computational techniques has been instrumental in resolving existing discrepancies and providing a deeper understanding of these chemical systems. The find- ings underscore the importance of careful data interpretation and emphasise the strengths and constraints of the combined methodologies. 1
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Structural Interpretation of NMR Spectroscopic Parameters in Nucleic Acids
Fukal, Jiří ; Sychrovský, Vladimír (advisor) ; Hrabal, Richard (referee) ; Munzarová, Markéta (referee)
Title: Structural Interpretation of NMR Spectroscopic Parameters in Nucleic Acids Author: Mgr. Jiří Fukal Supervisor: Dr. Vladimír Sychrovský Institutions: Charles University, Faculty of Mathematics and Physics, and Czech Academy of Sciences, Institute of Organic Chemistry and Biochemistry Abstract: Nuclear Magnetic Resonance (NMR) is versatile spectroscopy technique applicable to determination of both chemical and 3D structure of molecules. Elementary characterization of peptides, proteins and nucleic acids employs the 1 H and 13 C NMR measurements. Probing of 15 N and 17 O atoms usually requires advanced chemical preparation of molecules (labelling with relevant isotopes). 31 P NMR is in that regard exceptional due to 100% natural abundance of the isotope. Hence, NMR structural studies of a nucleic acid's backbone are aimed at the phosphate group. Pertinent spectral parameters include δ31P NMR shift and J-couplings involving the phosphorus atom (e.g. 3 JP,H3'). Structural interpretation of NMR spectra requires usage of adequate quantum chemistry method (QM method) and inclusion of effects due to molecular dynamic (MD). That is why plausible interpretation of the spectral parameters in nucleic acids may become computationally demanding. The benchmark of QM methodology for 31 P NMR calculation made possible...
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Determination of structure and dynamics of biomolecules by theoretical calculations of NMR spectroscopic parameters
Benda, Ladislav ; Sychrovský, Vladimír (advisor) ; Munzarová, Markéta (referee) ; Hrabal, Richard (referee)
iv Abstract Subject: Determination of structure and dynamics of biomolecules by theoretical calcu- lations of NMR spectroscopic parameters Author: Ladislav Benda, ladislav.benda@gmail.com Department/Institute: Institute of Organic Chemistry and Biochemistry, AS CR Supervisor: Dr. Vladim'ır Sychrovsk'y, Institute of Organic Chemistry and Biochemistry, AS CR, vladimir.sychrovsky@uochb.cas.cz Abstract: This doctoral work was focused on theoretical modeling of nuclear magnetic resonance (NMR) parameters in peptides and nucleic acids. Dependences of NMR para- meters on molecular structure and solvation were primarily modeled. Great emphasis was put on the comparison of the calculated data with the NMR experiment. The molecular models studied included the l-alanyl-l-alanine di-peptide (AA) and the phosphate group of nucleic acid backbone. Conformations of all three charged forms of AA in solution were determined and the respective pH-induced changes of experimental NMR chemical shifts and nuclear spin-spin coupling constants were explained. Dependences of NMR cross-correlated relaxation rates on the AA backbone geometry were calibrated. The 31 P NMR parameters in nucleic acid phosphate were systematically calculated in dependence on the backbone conformation and the phosphate solvation pattern. Qualitative rules...
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Determination of structure and dynamics of biomolecules by theoretical calculations of NMR spectroscopic parameters
Benda, Ladislav ; Sychrovský, Vladimír (advisor) ; Munzarová, Markéta (referee) ; Hrabal, Richard (referee)
iv Abstract Subject: Determination of structure and dynamics of biomolecules by theoretical calcu- lations of NMR spectroscopic parameters Author: Ladislav Benda, ladislav.benda@gmail.com Department/Institute: Institute of Organic Chemistry and Biochemistry, AS CR Supervisor: Dr. Vladim'ır Sychrovsk'y, Institute of Organic Chemistry and Biochemistry, AS CR, vladimir.sychrovsky@uochb.cas.cz Abstract: This doctoral work was focused on theoretical modeling of nuclear magnetic resonance (NMR) parameters in peptides and nucleic acids. Dependences of NMR para- meters on molecular structure and solvation were primarily modeled. Great emphasis was put on the comparison of the calculated data with the NMR experiment. The molecular models studied included the l-alanyl-l-alanine di-peptide (AA) and the phosphate group of nucleic acid backbone. Conformations of all three charged forms of AA in solution were determined and the respective pH-induced changes of experimental NMR chemical shifts and nuclear spin-spin coupling constants were explained. Dependences of NMR cross-correlated relaxation rates on the AA backbone geometry were calibrated. The 31 P NMR parameters in nucleic acid phosphate were systematically calculated in dependence on the backbone conformation and the phosphate solvation pattern. Qualitative rules...
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Thermochemical Properties of High Nitrogen Energetic Materials
Bartošková, Monika ; Munzarová, Markéta (referee) ; Potáček, Milan (referee) ; Jalový,, Zdeněk (referee) ; Vávrová, Milada (advisor)
The main goal of the presented thesis is a theoretical study of heat of formation for high-nitrogen energetic materials. A modification of the classical approach to the isodesmic reactions is realized with the intent that molecules on both sides of the corresponding equation have not only the same number of atoms but also approximately the same size and skeletal similarity. This approach is designated as a method "Alternative Isodesmic Reaction (AIR method)". At its base, using the DFT B3LYP / cc-pVTZ and B3PW91 / cc-pVTZ, for the high nitrogen heterocycles, which are selected from the group of triazoles, triazines, tetrazines, the enthalpy of formation values the gaseous phase f H°(298,g), were obtained whose values are close to the published f H°(298,g). Their application in the calculation of the relevant characteristics of these heterocycles detonation gave real values.
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