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Molecular simulations in structure analysis of intercalates
Veteška, Marek
The samples of hydrotalcite intercalated with pyrenetetrasulphonate acid were obtained. Their structure cannot be precisely determined by the analysis of X-ray data. The amount of water in the interlayer space and the structure of the samples differed considerably in dependence on humidity. Convenient procedures and minimization strategy were established on the base of X-ray data in the molecular mechanic and the molecular dynamic simulations. A procedure for using of the supramol software was made. This software enables deterministic searching of conformational space. Initial models from supramol were minimized in the Cerius2 software using the Universal force field and then they were eventually optimized by the molecular dynamics. The arrangement of molecules of pyrenetetrasulphonate acid and water was determined in the interlayer space of hydrotalcite for three different samples with different interlayer distances: The sample 1 prepared by RH = 0%: 9.83A; the sample 2 prepared by RH = 84%: 13.63A; the sample 3 prepared RH = 40%-50%: 11.74A a 12.81A. The results of these structures proved a large variability of the arrangement of the molecules in the interlayer space. The sample No. 3 seems to be unstable.
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Application of Molecular Simulations in Complex Structural Analysis of Layered Materials
Veteška, Marek ; Pospíšil, Miroslav (advisor) ; Demel, Jan (referee) ; Tokarský, Jonáš (referee)
Title: Application of Molecular Simulations in Complex Structural Analysis of Layered Materials Author: RNDr. Marek Veteška Department: Department of Chemical Physics and Optics Supervisor: RNDr. Miroslav Pospíšil, Ph.D., Dept. of Chemical Physics and Optics Abstract: Techniques of molecular simulations were used together with experimental measurements (X-ray diffraction, thermogravimetry, infrared spectroscopy, elemental analysis and others) to clarify the structure properties of various types of layered materials. The structure of Zn-Al-layered double hydroxide intercalated by pyrenetetra- sulfonate acid was solved. Depending on the relative humidity, the samples showed different arrangements with three planes of water molecules and with either one or two planes of pyrenetetrasulfonate anions. At the same time considerable variability of anions arrangement was demonstrated. The adsorption behavior of natural montmorillonite and montmorillonite modified by tetramethylammonium cations in relation to aniline and phe- nol was explored. Adsorption features differed according to both the type of adsorbed molecules and the type of adsorbents. An important role was played by the plane of water molecules right above the surface which medi- ated adsorption of anilines. The water plane area was reduced by...
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Molecular simulations in structure analysis of intercalates
Veteška, Marek
The samples of hydrotalcite intercalated with pyrenetetrasulphonate acid were obtained. Their structure cannot be precisely determined by the analysis of X-ray data. The amount of water in the interlayer space and the structure of the samples differed considerably in dependence on humidity. Convenient procedures and minimization strategy were established on the base of X-ray data in the molecular mechanic and the molecular dynamic simulations. A procedure for using of the supramol software was made. This software enables deterministic searching of conformational space. Initial models from supramol were minimized in the Cerius2 software using the Universal force field and then they were eventually optimized by the molecular dynamics. The arrangement of molecules of pyrenetetrasulphonate acid and water was determined in the interlayer space of hydrotalcite for three different samples with different interlayer distances: The sample 1 prepared by RH = 0%: 9.83A; the sample 2 prepared by RH = 84%: 13.63A; the sample 3 prepared RH = 40%-50%: 11.74A a 12.81A. The results of these structures proved a large variability of the arrangement of the molecules in the interlayer space. The sample No. 3 seems to be unstable.
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Molecular simulations in structure analysis of intercalates
Veteška, Marek ; Pospíšil, Miroslav (advisor) ; Beneš, Ludvík (referee)
The samples of hydrotalcite intercalated with pyrenetetrasulphonate acid were obtained. Their structure cannot be precisely determined by the analysis of X-ray data. The amount of water in the interlayer space and the structure of the samples differed considerably in dependence on humidity. Convenient procedures and minimization strategy were established on the base of X-ray data in the molecular mechanic and the molecular dynamic simulations. A procedure for using of the supramol software was made. This software enables deterministic searching of conformational space. Initial models from supramol were minimized in the Cerius2 software using the Universal force field and then they were eventually optimized by the molecular dynamics. The arrangement of molecules of pyrenetetrasulphonate acid and water was determined in the interlayer space of hydrotalcite for three different samples with different interlayer distances: The sample 1 prepared by RH = 0%: 9.83A; the sample 2 prepared by RH = 84%: 13.63A; the sample 3 prepared RH = 40%-50%: 11.74A a 12.81A. The results of these structures proved a large variability of the arrangement of the molecules in the interlayer space. The sample No. 3 seems to be unstable.
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