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Synthesis and coordination properties of TACN phosphinate derivatives
Kohúteková, Soňa ; Kubíček, Vojtěch (advisor) ; Gyepes, Róbert (referee)
The aim of this work is preparation and characterization of a ligand for a selective complexation of gallium (III). The ligand is a derivative of macrocycle NOTA with bis(phosphinic) pendant arm. Protonation constants and stability constants with copper (II), nickel (II), zinc (II) and gallium (III) cations were determined by potentiometric titrations. The ligand was also used for studying complexation kinetics with gallium (III) ions and might serve as a potential contrast agent for 68 Ga-PET.
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Aminophosphinic acids
Kruliš, Tomáš ; Kubíček, Vojtěch (advisor) ; Gyepes, Róbert (referee)
Two phosphinic acids were prepared: 1-hydroxy-ethan-1,1-bis[N,N- bis(karboxymethyl)aminomethyl]phosphinic acid; H6L1 and methylenebis[N,N- bis(karboxymethyl)aminomethyl]phosphinic acid; H6L2 . Acid-base and complexation properties were studied by potenciometric titrations. Complexes of both ligands with Cu2+ ions were studied in detail using UV/VIS spectrometry. Keywords: Organophosphorus synthesis, bisphosphinic acids, coordination properties
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Novel materials for nonlinear optics - salts and cocrystals of heteroaromatic bases
Kloda, Matouš ; Němec, Ivan (advisor) ; Gyepes, Róbert (referee)
The main issue of this master thesis is investigation of new compounds of aminopyrazine and 3-amino-1,2,4-triazine in consideration of their potential usage in the field of nonlinear optics. The focus of this thesis was finishing of characterisation of an adduct of aminopyrazine and boric acid prepared as a part of previous bachelor thesis, as well as preparation of salts and cocrystals combining 3-amino-1,2,4-triazine with selected acids. Prepared materials were characterised mainly by the means of vibrational spectroscopy and x-ray diffraction analysis. Prediction of nonlinear optical properties of selected molecules and interpretation of recorded vibrational spectra was based on quantum chemical calculations. Finally, measurements of second harmonic generation efficiency of selected powder samples were performed.
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Nové molekulární materiály pro nelineární optiku - příprava a detailní charakterizace
Mathauserová, Jana ; Němec, Ivan (advisor) ; Gyepes, Róbert (referee)
In this thesis both an experimental and computational study of selected prospective materials for nonlinear optics is presented. The main focus was put on 2-aminopyrimidinium hydrogen- phosphite (AMPPO3), a salt with high SHG efficiency and Type I. phase matching properties. AMPPO3 had been studied by our research group and its favourable qualities such as easy preparation, colourlessness, great water solubility and good crystallinity motivated further in- terest and the attempts for the growth of bulk single crystals from thermostated aqueous solu- tions as presented here. The products are meant to be probed by laser in a specific direction to determine the maximum SHG efficiency, so far the polarized microscopy study revealing the extreme dispersion effects is provided. AMPPO3 is an example of H-bond stabilized framework with both organic and inorganic building blocks. The computational study was led as to understand the structure which is typical for one of the classes of compounds exhibiting nonlinear optical properties. DFT implemented in parallel CP2K was used and for the comparison three other optically active materials of sim- ilar composition were studied - urea, guanylurea hydrogenphosphite and 2-aminopyrimidine- boric acid 3/2 cocrystal. After the constrained geometry optimization and cell...
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Preparation and characterization of new materials for metathesis and adsorption
Pastva, Jakub ; Čejka, Jiří (advisor) ; Gyepes, Róbert (referee) ; Koubek, Josef (referee)
The main objective of this work was to evidence versatile applications of ordered siliceous mesoporous materials, especially in adsorption and catalysis. For these reasons four mesoporous molecular sieves (SBA-15, SBA-16, MCM-41, and MCM-48) with different structures and textural properties have been chosen. To show the possible application of mesoporous molecular sieves as a CO2 adsorbent, magnesium oxide, and potassium carbonate were incorporated into SBA-15, SBA-16, and MCM-48 silicas. In order to avoid destruction of silica supports, a novel procedure based on the precipitation of magnesium acetate on the silica surface was developed. Subsequent in situ chemical conversion of magnesium acetate provided magnesium oxalate, while magnesium oxide was formed by calcination. To introduce potassium carbonate, silica modified with MgO was impregnated with potassium oxalate followed by its conversion to carbonate. All prepared mesoporous adsorbents preserved characteristic features of mesoporous molecular sieve (large surface areas, narrow pore size distributions). The comparison of carbon dioxide isotherms obtained on prepared samples revealed that their adsorption properties are influenced by the type of mesoporous structure. The SBA-15 silica containing magnesium oxide and promoted by potassium...
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