Search for dissertations about: "study of vibrational frequencies"

Showing result 1 - 5 of 24 swedish dissertations containing the words study of vibrational frequencies.

  2. 1. Physisorption of CO and N2O on ceria surfaces

    Author : Carsten Müller; Kersti Hermansson; Konstantin Neyman; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ceria; carbon monoxide; nitrous oxide; embedded cluster; physisorption; method of increments; CCSD T ; vibrational frequencies; Quantum chemistry; Kvantkemi; Quantum Chemistry; kvantkemi;

    Abstract : Physisorption of CO and N2O on surfaces of ceria (CeO2) was investigated by means of high-level quantum-mechanical embedded cluster calculations. Both systems have high relevance in the field of environmental chemistry and heterogeneous catalysis. READ MORE

  4. 2. Vibrational and Structural Characterisation in Two Perovskite Challenges: A Density Functional Theory Study

    Author : Erik Jedvik Granhed; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; phonon; chemical expansion; materials modelling; oxyhydride; polaron; vibrational analysis; BaTiO3; BaZrO3; anti-ferrodistortive; density functional theory;

    Abstract : The modelling of perovskites using density functional theory (DFT) can sometimes be a challenge with many different states very close in energy. In particular, the tilting of the inscribed octahedron, as well as the formation of electron polarons, leads to states with energy differences in the meV range. READ MORE

  5. 3. A Theoretical Study of Charge Transport in Molecular Crystals

    Author : Elham Mozafari; Sven Stafström; Magnus Johansson; Linköpings universitet; []
    Keywords : Molecular Crystals; Charge transport; Polaron; Holstein model; Peierls coupling;

    Abstract : The main objective of this thesis is to provide a deeper understanding of the charge transport phenomena occuring in molecular crystals. The focus is on the stability and the dynamics of the polaron as the charge carrier.To achieve this goal, a series of numerical calculations are performed using the semi-emprical "Holstien-Peierls" model. READ MORE

  6. 4. Electronic and dynamical aspects of the stability of metallic structures

    Author : Babak Sadigh; KTH; []
    Keywords : ;

    Abstract : The structural phase stability of several transition metalsystems have been studied, using first-principles electronicstructure calculations. Frozen phonon techniques have been usedto study the details of structural phase transformations e.g. READ MORE

  7. 5. A Spectroscopic Study of Interfacial Films: Internal Structuring, Stability, and Hydration

    Author : Jonathan F. D. Liljeblad; Mark W. Rutland; C. Magnus Johnson; Rob Walker; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Monolayers of molecules are capable of completely changing the nature of surfaces and their interactions with the surroundings despite their almost negligible thickness. In the research presented in this doctoral thesis the surface specific technique Vibrational Sum Frequency Spectroscopy (VSFS) was combined with the Langmuir trough to investigate various manifestations of monolayers, such as biomimetic membranes, mono methyl branched long chain fatty acids in contact with air, and hydrophobic silane monolayers in contact with water. READ MORE