Sökning: "electronic circular dichroism"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden electronic circular dichroism.

1. 1. Long-range intermolecular dispersion forces and circular dichroism spectra from first-principles calculations

   Författare :Auayporn Jiemchooroj; Bo Sernelius; Patrick Norman; Kenneth Ruud; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; van der Waals forces; dispersion forces; dispersion coefficients; polarizability; electronic circular dichroism; Physics; Fysik;

   Sammanfattning : This work presents first-principles calculations of long-range intermolecular dispersion energies between two atoms or molecules and of electronic circular dichroism spectra of chiral molecules. The former is expressed in terms of the C6 dipole-dipole dispersion coefficients Δε, and the latter is given in terms of the extinction coefficient. LÄS MER

3. 2. Excitation and Excited State Properties of Heterocyclic Chromophores. Indole and Purine Derivatives of Biological Significance

   Författare :Bo Albinsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; linear dichroism LD ; fluorescence polarization anisotropy FPA ; electronic excitations; magnetic circular dichroism;

   Sammanfattning : Proteins and nucleic acids absorb light in the near-UV due to the presence of aromatic heterocyclic chromophores. In this work linear dichroism (LD) in combination with fluorescence polarization anisotropy (FPA) and magnetic circular dichroism (MCD) is used to investigate electronic excitations and excited states of indole derivatives, purine derivatives, the wye base, 2-phenylindole and 4',6-diamidino-2-phenylindole (DAPI). LÄS MER

4. 3. Membrane Orientation Studies with Polarized Light Spectroscopy

   Författare :Malin Ardhammar; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lipid vesicle; membrane orientation; flow linear dichroism; oriented circular dichroism;

   Sammanfattning : Lipid vesicles are versatile tools in modern biophysical science. They can be used as models of the cell membrane, to examine permeability, stability and behavior of molecules in the bilayer. They may act as transporters in a pharmacological context, designed to deliver their cargo to a certain place in the patient. LÄS MER

5. 4. Theoretical Studies on Electronic and Vibrationally Resolved Multi-Photon Absorption and Dichroism

   Författare :Na Lin; Yi Luo; Marcel Nooijen; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Multi-photon absorption and dichroism; Vibronically resolved spectroscopy; Quantum chemistry; Kvantkemi;

   Sammanfattning : This thesis presents time-dependent density functional theory studies on electronic and vibronically resolved linear and nonlinear optical absorption and dichroism spectra of organic molecules. Special attention has been paid to the influence of solvent environment and molecular vibrations on one-, two- and three-photon absorption and one- and two-photon circular dichroism. LÄS MER

7. 5. A study of the stereochemistry and electronic transitions of cyclic and acyclic thioamides by crystallography, spectroscopy and computational methods

   Författare :Knut Rang; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; UV and CD spectroscopy; rotational barriers; DNMR; X-ray; N -bis[ S -1-phenylethyl]-thiourea; N; attractive steric effect; chiral; phenyl or H- rhodanines; 3- alkyl or aralkyl -5- methyl; Conformations; electronic transitions; molecular mechanics; enantiom; Organic chemistry; Organisk kemi;

   Sammanfattning : Analysis of conformations and electron transitions of 3-(alkyl or aralkyl)-5-(methyl or phenyl)rhodanines with analogues and N,N'-bis[(S)-1-phenylethyl]-thiourea have been performed by X-ray crystallography, 1H NMR, molecular mechanics, ultraviolet spectroscopy and for the chiral rhodanines, enantiomer chromatography and circular dichroism spectroscopy. The magnitude of rotational barriers has been determined. LÄS MER