Sökning: "CASSCF calculations"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden CASSCF calculations.

1. 1. An Ultrafast Spectroscopic and Quantum-Chemical Study of the Photochemistry of Bilirubin : Initial Processes in the Phototherapy for Neonatal Jaundice

   Författare :Burkhard Zietz; Tomas Gillbro; Jouko Korppi-Tommola; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bilirubin; Phototherapy; Neonatal Jaundice; Femtosecond Spectroscopy; CASSCF; TD-DFT; Isomerisation Dynamics; Biophysical chemistry; Biofysikalisk kemi;

   Sammanfattning : Bilirubin is a degradation product of haem, which is constantly formed in allmammals. Increased levels of bilirubin in humans lead to jaundice, a conditionthat is very common during the first days after birth. This neonataljaundice can routinely be treated by phototherapy without any serious sideeffects. LÄS MER

3. 2. Calculated Potential Energy Surfaces and Vibrational Analysis

   Författare :Niclas Forsberg; Beräkningskemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Benzene; HCO; NEMO; Imaginary Level Shift; Double Harmonic Approximation; Potential Energy Surface; CASPT2; Franck-Condon Factors; CASSCF; p-Benzosemiquinone; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi;

   Sammanfattning : The focus of this thesis is on the calculation of potential energy surfaces and on the study of vibrational properties. For example: - We have developed a new method for calculation of Franck-Condon factors. - We have calculated full energy surfaces of the ground (X2A’) the excited (B2A’) states of the formyl radical. LÄS MER

4. 3. Multiconfigurational perturbation theory

   Författare :Kerstin Andersson; Karlstads universitet; []
   Nyckelord :Electron correlation; CASSCF; multiconfigurational second-order perturbation theory; CASPT2; ozone; C; N; O; F; Si; P; S; Cl; Ni; benzene; pyridine; pyrazine; pyrimidine; pyridazine; s-triazine; electric properties; excited states; spectroscopic data;

   Sammanfattning : The aim of the thesis is to analyze a method which describes the electron correlation in atoms and molecules. The method is based on Rayleigh-Schrödinger perturbation theory with a partitioning of the Hamiltonian into a fairly simple zeroth-order operator and a perturbation operator. LÄS MER

5. 4. Ab initio simulations of core level spectra : Towards an atomistic understanding of the dye-sensitized solar cell

   Författare :Ida Josefsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; multiconfigurational quantum chemistry; CASSCF calculations; core-level spectroscopy; x-ray photoelectron spectroscopy; x-ray absorption; resonant x-ray scattering; dye solar cells; transition metals; kemisk fysik; Chemical Physics;

   Sammanfattning : The main focus of this thesis is ab initio modeling of core level spectra with a high-level quantum chemical description both of the chemical interactions and of local atomic multiplet effects. In particular, the combination of calculations and synchrotron-based core-level spectroscopy aims at understanding the local structure of the electronic valence in transition metal complexes, and the details of the solvation mechanisms of electrolyte solutions, systems relevant for the dye-sensitized solar cell. LÄS MER

7. 5. Electronic Structure and Core-Hole Dynamics of Ozone : Synchrotron-radiation based studies and ab-initio calculations

   Författare :Karoline Wiesner; Svante Svensson; Olle Björneholm; Robert E. Continetti; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik;

   Sammanfattning : The electronic structure of the ozone molecule O3 has been studied with spectroscopy techniques and computations. The investigation was focused on O3 in a core-hole state. The electronic configuration and the nuclear dynamics have been found to be highly correlated. LÄS MER