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Computational Study of the Interaction and adhesioin energies of polyaniline models with surfaces of the selected materials.
Maixner, Michal ; Burda, Jaroslav (advisor) ; Tokarský, Jonáš (referee)
This work is focused on the properties of polyaniline placed on the model of silicate surface, namely its adhesion energy and spectra of polyaniline with different charge, computed by means of quantum chemistry. Computed spectra were compared with experimental data. The DFT metod ω-B97XD with 3-21G base was used for optimalization of the complex model and for determination of vibrational spectra the DFT metod ω-B97XD with 6-31G(d,p) base was used. Evaluation of the adhesion energy DFT metod ω-B97XD with 6-31G* base was used. The adhesion energy computed by interpolation to infinite polymer was 1,9kcal/mol. Computed Raman spectra was fit to experimental data. Spectrum found by this metod was similar to experimental in some aproximation, but more detail look would reavel some differences caused by not including of enviroment and of interaction between polyaniline
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Accurate Quantum Mechanical Calculations on Noncovalent Interactions: Rationalization of X-ray Crystal Geometries by Quantum Chemistry Tools
Hostaš, Jiří ; Hobza, Pavel (advisor) ; Burda, Jaroslav (referee) ; Jurečka, Petr (referee)
There is a need for reliable rules of thumb for various applications in the area of biochemistry, supramolecular chemistry and material sciences. Simultaneously, the amount of information, which we can gather from X-ray crystal geometries about the nature of recognition processes, is limited. Deeper insight into the noncovalent interactions playing the most important role is needed in order to revise these universal rules governing any recognition process. In this thesis, systematic development and study of the accuracy of the computational chemistry methods followed by their applications in protein DNA and host guest systems, are presented. The non-empirical quantum mechanical tools (DFT-D, MP2.5, CCSD(T) etc. methods) were utilized in several projects. We found and confirmed unique low lying interaction energies distinct from the rest of the distributions in several amino acid−base pairs opening a way toward universal rules governing the selective binding of any DNA sequence. Further, the predictions and examination of changes of Gibbs energies (ΔG) and its subcomponents have been made in several cases and carefully compared with experiments. We determined that the choline (Ch+) guest is bound 2.8 kcal/mol stronger (calculated ΔG) than acetylcholine (ACh+) to self-assembled triple helicate rigid...
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Interaction of Metal Cations in Bioorganic Environment. Computational Study Using Quantum Mechanics and Molecular MechanicsTools.
Futera, Zdeněk ; Burda, Jaroslav (advisor) ; Bouř, Petr (referee) ; Clark, Tim (referee)
Interactions of Metal Cations in Bioorganic Environment Computational Study Using Quantum Mechanics and Molecular Mechanics Tools Zdeněk Futera Biologically relevant interactions of piano-stool ruthenium(II) complexes with ds-DNA are studied by QM/MM computational technique. The whole re- action mechanism is divided into three phases - hydration of [RuII (η6 - benzene)(en)Cl]+ , consequent binding DNA and final intra-strand cross-link formation between two adjacent guanines. Free energy profiles of all reactions are explored by QM/MM MD umbrella sampling approach where the Ru(II) complex is described by DFT. For that purpose, special QM/MM software was developed to couple Gaussian and Amber programs. Calculated free energy barriers of Ru(II) hydration as well as DNA binding process are in good agreement with experimentally determined rate constants. Reaction pathway for cross-link formation was predicted that is feasible from both thermodynamical and kinetical point of view.
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Combined QM/MM decsription of interaction of Ru(II) 'piano-stool' organometallic complexes with oligomer models of DNA
Zábojníková, Tereza ; Burda, Jaroslav (advisor) ; Sychrovský, Vladimír (referee)
This work is focused on 4 organometalic drugs with "piano-stool" Ru(II) structure: these complexes are: nalidixic acid, thio-nalidixic acid, ofloxacin and cinoxacin. Thermodynamic parameters of three type of reactions with water were analyzed for each of these four complexes. All complexes were examined in both protonated and deprotonated state, since all of these complexes are acids and they behave differently in acidic and neutral enviroment. Optimalization was performed using DFT method B3PW91 in basis 6-31+G*. Energies were calculated in basis 6-311++G(2df,2pd) using DFT method B3LYP and NPA analysis was performed for finding partial charges on atoms.
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Computational Study of the Interactions of Transition Metal Complexes with Biomolecules Using Quantum Chemical Methods.
Šebesta, Filip ; Burda, Jaroslav (advisor) ; Sochorová Vokáčová, Zuzana (referee)
It has been proven that platinum complexes are active in anticancer treatment as well as several other transition metals. There is an effort in recent medicine to replace cisplatin complexes by drugs with smaller side effects. This work focuses on the reaction of 5'-dGMP (2'-deoxyguanosine- 5'˗monophosphate) with a platinum complex PtIV (dach)Cl4 (dach=diaminocyclohexane) forming PtIV (dach)Cl3(N7-cGMP) complex. The explored reaction can be divided into two (independent) steps: cyclization of phosphate and substitution reaction where a new complex with coordinate- covalent bond between platinum atom and nitrogen N7 of guanine is formed releasing chloride particle. Here I studied geometry parameters which are important in the above mentioned reaction. The reaction course is observed from the thermodynamic point of view. The structures were optimized at the DFT level with B3LYP functional in basis set 6-31G* and PCM/UA0 solvation model. The energy parameters and electron density distribution were computed at the B3LYP/6˗311++G(2df,2pd) level in the D˗PCM/sUAKS solvation model.
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Non - covalent interactions in fundamental biological processes
Klusák, Vojtěch ; Rulíšek, Lubomír (advisor) ; Burda, Jaroslav (referee) ; Šponer, Jiří (referee)
Charles University in Prague Faculty of Science Department of Physical and Macromolecular Chemistry Non-covalent interactions in fundamental biological processes Doctoral Thesis Abstract Mgr. Vojtěch Klusák Supervisor: Mgr. Lubomír Rulíšek, CSc. Institute of Organic Chemistry and Biochemistry AS CR Center for Biomolecules and Complex Molecular Systems Praha 2010 2 3 Universita Karlova v Praze Přírodovědecká fakulta Katedra fyzikální a makromolekulární chemie Nekovalentní interakce v základních biologických procesech Souhrn disertační práce Mgr. Vojtěch Klusák Školitel: Mgr. Lubomír Rulíšek, CSc. Ústav organické chemie a biochemie AV ČR Centrum biomolekul a komplexních molekulárních systémů Praha 2010 4 5 Introduction Understanding inter- and intra-molecular interactions is the key for our insight into the properties of the biomolecular systems which, in turn, maintain and govern virtually all the processes in biology. Attempts to draw the structure-function relationship at the atomistic or electronic level bring us quite often beyond experimental resolution and capabilities. Modern tools of computational chemistry enable us to focus with satisfactory degree of reliability on the details of the studied process, gather additional (often complementary) information and ascribe particular structural features to...
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Noncovalent Interactions in the Gas Phase and Aqueous Solution: Theoretical Study
Zendlová, Lucie ; Hobza, Pavel (advisor) ; Burda, Jaroslav (referee) ; Vondrášek, Jiří (referee) ; Jurečka, Petr (referee)
EAPUr rr|lclltal \ alLlť5' 5 Conclusions :, , . In the ia) part of present work we c intera cti on b etween u d"',il ". . . thy;';; il:'::: :íJTj.:lÍ' lI jl.#.ffiJ,lil itt8:"é'siia small number or*u.",7nJ organió solvent ňr"."i", (CH3.H, solvents yů[T"i^f.completely different interactions between the bases and the b"''" p.'"{ ;' "idilnn il#} il-t ÍT:!fl,-. i: : " o:] Y" .'h:.-S,t.* tu,", ot tt," moleóule Iuórc 'u'r' u property, and the'. .'l,'..,ťff,.'*lt'Lť':.lill:ilF.S'T!,l;situated above or belolthe !Á; ;;i. ;';;lě'"o ri," olašó ň"l"-.\,," ,, unique y"J::fiffii:x::. ."n'o*ison with otr,!. .otu"nt,, uň.'r,"í'ř;;.". are the In the ib) part_of present work based on the MD, SCC_DDFTB_D and ;"",'.Y|Tť'.#1.:."ffi i"T."lrJ'".r""u.'".XincorporateJ."-oŇTduplexwe i) Replacing nucleic acid base by modified nucleobase X leads.*:'] ,o Structural changes of the centrď -uuš"-pui. Gtu.tarrangement of central modified base pairs). ónli with ttresma'lest modified nucleobase p 'r'" Á.iJ.;;*;;.í' (A-P, P-T) stay planar. In the case 'of.B-T, Á-il.;';6 in specificorientation, one of the modified nuú"JÁ""x"*íto.""a outfrom DNA duplex. ii) Incre, .,""olr'iT"i1iTi1fi" or modified nucleobase X increases rhe iii) The highest s.ďectivity among- all base ana|ogue studied wasfound for modified nu"l"obus" O In the secono pu* of...
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The theoretical exploration of the interactions of dirhodium complexes.
Kovaľ, Tomáš ; Burda, Jaroslav (advisor) ; Záliš, Stanislav (referee)
This work focuses on the study of interactions of the Diaqua-tetrakis(-acetylato)dirhodium(II,II) complex. This complex belongs to compounds of transition metals, which show activity in anticancer treatment. In this work, the interactions of this complex with ammonia and guanine are studied. The interactions with ammonia are represented by a replacement reaction of oxygen from acetyl ligand or aqua ligand. Another reaction is the replacement of water bonded to rhodium by guanine. Guanine can form a bond to rhodium with oxygen O6 or nitrogen N7. Optimization of the structures are made at the DFT level with 6-31G* basis set. For reactions with ammonia transition states were found. NPA charge analyses, thermodynamical and kinetical analyses were performed. All these analyses were done at the DFT level with aug-cc-pvdz basis set. To describe the electronic structure of rhodium atoms pseudopotentials and pseudobasis were used. All calculations were modeled in gas phase.
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