Sökning: "Complex Polarization Propagator"
Hittade 5 avhandlingar innehållade orden Complex Polarization Propagator.
1. Implementation of complex polarization propagator theory for linear response properties of large molecular systems
Sammanfattning : Since its beginning, the remarkable development from the first commercially available computers toward exascale supercomputers just within the span of a lifetime has been closely intertwined with the perpetual quest for the utilization of the arising computing power for the avail of theoretical chemistry. With the aim of further pushing the limits of computationally accessible molecular system sizes, this thesis includes the presentation of programming efforts, which brought forth two quantum chemical software codes, as well as a range of ab initio studies on carbon-based systems, enabled by the former. LÄS MER
2. Extending relativistic linear response theory to address solvent effects
Sammanfattning : The central aim of this thesis is to derive, implement and test new methods to calculate various types of spectroscopies of compounds containing heavy elements in an aqueous environment. Methods that can target such systems have to consider the following:(i) It is crucial to take relativistic effects into account. LÄS MER
3. Time-dependent molecular properties in the optical and x-ray regions
Sammanfattning : Time-dependent molecular properties are important for the experimental characterization of molecular materials. We show how these properties can be calculated, for optical and x-ray frequencies, using novel quantum chemical methods. LÄS MER
4. First-principles calculations of long-range intermolecular dispersion forces
Sammanfattning : This work presents first-principles calculations of long-range intermolecular dispersion energies between two atoms or molecules as expressed in terms of the C6 dipole-dipole dispersion coefficients. In a series of publications, it has been shown by us that the complex linear polarization propagator method provides accurate ab initio and first-principles density functional theory values of the C6 dispersion coefficients in comparison with those reported in the literature. LÄS MER
5. Long-range intermolecular dispersion forces and circular dichroism spectra from first-principles calculations
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
