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Violation and Conservation of Symmetries in Atomic Systems
Uhlířová, Tereza ; Zamastil, Jaroslav (advisor) ; Čížek, Martin (referee) ; Pittner, Jiří (referee)
This thesis focuses on the three pillars of any high-precision ab initio calculation: on the Hartree-Fock (HF) model, on the choice of a suitable basis set, and on the inclusion of electron correlation. We start with a study of singular properties of the HF model. Specifically, we sys- tematically investigate the stability of all atomic closed-shell systems up to xenon using a symmetry-adapted Thouless stability matrix. To obtain a global view on the stability of a particular isoelectronic sequence, we employ high-order perturbative method and then analyze the obtained series. This allows us to determine onsets of spin and orbital symmetry breaking. In addition, we also propose a physical meaning of the instabilities. In the next part of this thesis, we focus on the use of the Sturmian basis set for relativistic calculations. We propose a numerically stable algorithm for the evaluation of one- and two-electron matrix elements. Thus we defeat the major impediment of a wider use of this basis set in precise atomic structure calculations. The use of the proposed method and its significance is illustrated on a series of calculations. For instance, we evaluate the so-called parity non-conserving amplitude for cesium; this is a second-order property and thus greatly depends on the accuracy of the used wave...
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Excitation wavelength-dependent Raman spectra of single-layer graphene-phtalocyanine hybrid systems
Uhlířová, Tereza ; Vlčková, Blanka (advisor) ; Němec, Ivan (referee)
A systematic chemical and spectroscopic approach to evaluation of the effect of single-layer graphene (SLG) on Raman spectra of free-base phthalocyanine (H2Pc) in glass/SLG/H2Pc hybrid systems has been developed. By a combi- nation of electronic absorption spectra, Raman spectra at five excitation wave- lengths (532, 633, 647, 785 and 830 nm) and excitation profiles of H2Pc Raman spectral bands, the constitution of the three prepared hybrid sysems has been es- tablished in the following manner: Hybrid system I comprises probably a bilayer of H2Pc molecules, system VI approximately a monolayer of H2Pc, and system X a slightly reorganized monolayer of H2Pc molecules. Micro-Raman spectral map- ping of all three hybrid systems yielded H2Pc spectral bands (together with the SLG spectral bands) at all five excitation wavelengths. By contrast, for all three HOPG/H2Pc reference systems (HOPG = highly oriented pyrolytic graphite), prepared by the same procedure as the corresponding samples, H2Pc signal was detected only at 633 and 647 nm excitations. A selective increase of normalized Raman intensities of H2Pc spectral bands for the glass/SLG/H2Pc monolayer hybrid systems at 830 nm was revealed on the basis of a mutual comparison of Raman excitation profiles of all three samples of glass/SLG/H2Pc hybrid systems....
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Singular Behavior of the Hartree-Fock Equations
Uhlířová, Tereza ; Zamastil, Jaroslav (advisor) ; Čížek, Martin (referee)
The non-linear Hartree-Fock (HF) equations are usually solved via the iterative self-consistent field method. However, there is no a priori guarantee of convergence, especially in systems with strong electron correlation where symmetry breaking occurs. This work focuses on closed- shell systems in the HF approximation and the (in)stability of the found solutions, and proposes new deterministic methods for the localization of both symmetry-adapted and broken symmetry solutions. We employ a perturbative method and show how one can always obtain a symmetry-adapted solution of the HF equations. We also determine the radius of convergence, related to the existence of at least one bound state, of the perturbative series. Next, we rederive the matrix of stability and adapt it to spin and orbital symmetry. Calculation of higher energy variations follows, first in terms of spin-orbitals and then orbitals. Motivated by the investigation of the structure of a broken-symmetry solution, we propose a new deterministic method for the localization of a broken-symmetry solution. The general expressions are verified by reformulating the stability conditions for simple cases. The proposed methods are successfully applied to helium-, beryllium- and neon-like systems.
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Excitation wavelength-dependent Raman spectra of single-layer graphene-phtalocyanine hybrid systems
Uhlířová, Tereza ; Vlčková, Blanka (advisor) ; Němec, Ivan (referee)
A systematic chemical and spectroscopic approach to evaluation of the effect of single-layer graphene (SLG) on Raman spectra of free-base phthalocyanine (H2Pc) in glass/SLG/H2Pc hybrid systems has been developed. By a combi- nation of electronic absorption spectra, Raman spectra at five excitation wave- lengths (532, 633, 647, 785 and 830 nm) and excitation profiles of H2Pc Raman spectral bands, the constitution of the three prepared hybrid sysems has been es- tablished in the following manner: Hybrid system I comprises probably a bilayer of H2Pc molecules, system VI approximately a monolayer of H2Pc, and system X a slightly reorganized monolayer of H2Pc molecules. Micro-Raman spectral map- ping of all three hybrid systems yielded H2Pc spectral bands (together with the SLG spectral bands) at all five excitation wavelengths. By contrast, for all three HOPG/H2Pc reference systems (HOPG = highly oriented pyrolytic graphite), prepared by the same procedure as the corresponding samples, H2Pc signal was detected only at 633 and 647 nm excitations. A selective increase of normalized Raman intensities of H2Pc spectral bands for the glass/SLG/H2Pc monolayer hybrid systems at 830 nm was revealed on the basis of a mutual comparison of Raman excitation profiles of all three samples of glass/SLG/H2Pc hybrid systems....
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The Janus-faced Landscape. Representing the landscape of Rakovnik and Krivoklat in publications of the Rakovnik's Museum Society.
Uhlířová, Tereza ; Šima, Karel (advisor) ; Randák, Jan (referee)
In my Diploma Thesis, I deal with the way how the Rakovnik's Museum Society represented the landscape of Rakovnik and Krivoklat in their bulletins and in other regional publications in the early 20th century. It is a cultural-political analysis of the authors' manner of interpreting the Regions of Rakovnik and Krivoklat as a unified, specific, distinctive, mythmaking region, etc. in their texts, which means how its borders are defined, what elements are considered as the landscape features, how the literary- folkloric image of the region is created, the ways the land could be useful for human and which famous people are connected with this region. The emphasis is also placed on the question whether, and possibly, how the authors' position is reflected in the region's image. I deal with the research issues in connection with the concept of "the landscape as a story" or "the landscape memoirs", i.e. with a constructivist approach to the region, whose constitution is always culturally and socially conditioned. Key words: representation, landscape, museum society, Regions of Rakovnik and Krivoklat Powered by TCPDF (www.tcpdf.org)
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Význam Slováckých slavností vína pro rozvoj regionu
Uhlířová, Tereza
The bachelor thesis focuses on the Slovacko Festival of Wine and Open Monuments in Uherske Hradiste ("Slovácké slavnosti vína a otevřených památek v Uherském Hradišti"). The aim of the thesis is to evaluate the importance of the wine festival for development of the region and to provide some recommendations in order to eliminate possible negative impacts and to increase the number of visitors as well as the benefits of the event. To achieve this objective, the main methods used were primary marketing survey and secondary marketing research. The conclusion contains several proposals and recommendations to improve the satisfaction of visitors, locals, administrators, regional sellers, but also of other entities that are affected by this event.
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