Sökning: "Delocalization"

Visar resultat 1 - 5 av 22 avhandlingar innehållade ordet Delocalization.

1. 1. Delocalization in nonperiodic systems

   Författare :Lars Kroon; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The localization properties of non-interacting linear excitations in one-dimensional aperiodically ordered structures are investigated from a theoretical point of view. The models used have various relevance for real systems, like quasicrystals, photonic crystals, and deterministic aperiodic superlattices. LÄS MER

3. 2. Electronic and Vibrational Coherence in Photosynthetic and Model Systems

   Författare :Mirianas Chachisvilis; Kemisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemi; Chemistry; Ultrafast relaxation; Porphyrins; Delocalization; Anisotropy; Wavepacket; Vibrational Coherence; Excitons; Electronic coherence; Energy transfer; Femtosecond spectroscopy; Photosynthesis;

   Sammanfattning : Ultrafast optical response and excitation energy dynamics in light harvesting pigment-protein complexes and in a few model systems have been studied both experimentally and theoretically. Femtosecond light pulses were employed to excite the system and monitor the subsequent time evolution of the transient absorption kinetics and anisotropy. LÄS MER

4. 3. Understanding Atoms and Covalent Bonds. An exploration by Thomas-Fermi and one-electron theories

   Författare :William Eek; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum ergodicity; delocalization; covalent bonding; atomic reactivity; Thomas-Fermi theory;

   Sammanfattning : .... LÄS MER

5. 4. Aqueous Solutions as seen through an Electron Spectrometer : Surface Structure, Hydration Motifs and Ultrafast Charge Delocalization Dynamics

   Författare :Niklas Ottosson; Svante Svensson; Olle Björneholm; Gunnar Öhrwall; Clemens Heske; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Water; Aqueous solutions; Ions; Molecular Hydration; Electron dynamics; Atmospheric Chemistry; Hydrolysis; Acid-Base Chemistry; Interatomic Coulombic Decay; ICD; Liquid Micro-Jet; X-ray Photoelectron Spectroscopy; XPS; Auger Electron Spectroscopy; AES; MAX-lab; BESSY; Physics; Fysik; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : In spite of their high abundance and importance, aqueous systems are enigmatic on the microscopic scale. In order to obtain information about their geometrical and electronic structure, simple aqueous solutions have been studied experimentally by photo- and Auger electron spectroscopy using the novel liquid micro-jet technique in conjunction with synchrotron radiation. LÄS MER

7. 5. Functional and Modular As=C and P=C Group Motifs

   Författare :Daniel Morales Salazar; Andreas Orthaber; Jose Goicoechea; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; materials; physical chemistry; arsaalkenes; phosphaalkenes; DBU; fluorene; photochemistry; arsenic; phosphorus; carbon; hydrogen; sulfur; gold; copper; organic materials; organic electronics; molecular electronics; polymers; transition metal complexes; molecular materials; small molecule; hydrogen bonding; electrochemistry; cyclic voltammetry; chronoamperometry; electropolymerization; artificial intelligence; potentiodynamic; modularity; functionality; XPS; DFT; π-conjugation effects; 2D-NMR; disilenes; siliconoids; group motifs; functional group; emergence; reactivity; reactive systems; organometallic complexes; π-delocalization; low-coordinate; main group chemistry; heavy p-block elements; pnictogens; copper I complex; gold I complex; photosensitizer; XRD; spectroelectrochemistry; electrochromism; smart materials; synthesis; phosphaalkene ligands; imine ligands; hysteresis-like criteria; representative settings; optimal criteria; transient covalence; interactive image; conformer; isomer; ligand scrambling; nanomaterials; stimuli-responsive; optical properties; ligand design; molecular design; X-ray crystallography; emission; self-assembly; As=C; Si=Si; P=C; multiple bond; equilibrium; heteroalkenes; alkenes; reversibility; Raman; ATR-FTIR; ERDA; Kemi; Chemistry;

   Sammanfattning : This work focuses on the design, synthesis, characterization, and application projections of low-coordinated heavy pnictogen-containing (described by the generic letter E, hence E=C) phosphaalkenes (P=C) and arsaalkenes (As=C), with emphasis on the E=C group motifs. The work aims to understand their functional and modular character, reactivity, and potential applications by stabilizing, isolating, and characterizing these species in low-coordination environments. LÄS MER