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Quantum dynamics of small molecules
Augustovičová, Lucie ; Soldán, Pavel (advisor) ; Čurík, Roman (referee) ; Fišer, Jiří (referee)
This thesis deals with the process of molecular ions formation in interstellar space, which played an important role in the early Universe. A large part of the work focuses on the theoretical study of quantum dynamics of the process of radiative association pre- dominantly induced by dipole transitions. The effect of quadrupole transitions on the radiative association have also been taken into account, which has been studied for the first time. Furthermore, spectroscopic characteristics of rovibronic transitions of selected di- atomic ions for the study of cosmological variability of fundamental constants were determined. The main outcomes of the thesis include the characterization of depopulation of metastable levels He (23S) and He (21S) due to radiative collisions with hydrogen, helium and lithium ions, i. e. He + A+ → HeA+ + hν. Within the study quantum dynamics calculations were carried out using a fully quan- tal approach. Studied spontaneous and stimulated processes on a specific spin manifold were characterized by energy-dependent cross sections and temperature-dependent rate coefficients. Compared to previous published works by other authors highly excited electronic states are considered. The results showed that a) the spontaneous radiative association contributes significantly to the...
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Quantization of dynamics of molecular rattleback.
Bačo, Zsolt ; Čížek, Martin (advisor) ; Čurík, Roman (referee)
Title: Quantization of dynamics of molecular rattleback Author: Zsolt Bačo Institute: Institute of Theoretical Physics Supervisor: doc. RNDr. Martin Čížek, Ph.D., Institute of Theoretical Physics Abstract: This thesis has a theoretical character and is dealing with the prob- lem of a molecular rattleback from the quantum perspective, based on knowledge from classical physics of the same system. It is a rotor which doesn't conserve a direction of rotation. The aim is a quantization of the system's energy, what is an objective for a matrix representation of hamiltonian and consecutive diago- nalization, for what a suitable mathematical apparatus is needed to be built. In this thesis, there are derivated equations in detail, which are needed for matrix elements of hamiltonian. The next aim is a study of spectrum of hamiltonian gained by numerical computes, specifically a convergence of approximate values and their statistics. Based on the spectrum's statistics, there is a discussion about the chaotic character of the system. The main contribution of this thesis is the method of computing energetic levels of rotating objects in potential. Keywords: quantum dynamics, energy spectrum, rotational movement, rattleback
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Quantum dynamics of small molecules
Augustovičová, Lucie ; Soldán, Pavel (advisor) ; Čurík, Roman (referee) ; Fišer, Jiří (referee)
This thesis deals with the process of molecular ions formation in interstellar space, which played an important role in the early Universe. A large part of the work focuses on the theoretical study of quantum dynamics of the process of radiative association pre- dominantly induced by dipole transitions. The effect of quadrupole transitions on the radiative association have also been taken into account, which has been studied for the first time. Furthermore, spectroscopic characteristics of rovibronic transitions of selected di- atomic ions for the study of cosmological variability of fundamental constants were determined. The main outcomes of the thesis include the characterization of depopulation of metastable levels He (23S) and He (21S) due to radiative collisions with hydrogen, helium and lithium ions, i. e. He + A+ → HeA+ + hν. Within the study quantum dynamics calculations were carried out using a fully quan- tal approach. Studied spontaneous and stimulated processes on a specific spin manifold were characterized by energy-dependent cross sections and temperature-dependent rate coefficients. Compared to previous published works by other authors highly excited electronic states are considered. The results showed that a) the spontaneous radiative association contributes significantly to the...
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