Sökning: "photodissociation dynamics"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden photodissociation dynamics.

  1. 1. Ultrafast Photo-induced Reaction Dynamics of Small Molecules

    Författare :Malin Kadi; Jan Davidsson; Eva Åkesson; Sören Keiding; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; pump-probe spectroscopy; reaction dynamics; photodissociation; aryl halides; spin-orbit coupling; ab initio calculations; molecular dynamics; vibrational wavepackets; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

    Sammanfattning : The main focus of this thesis is the investigation of the dissociation dynamics of aryl halides using femtosecond pump-probe spectroscopy. In the monohalogenated aryl halides, iodo-, bromo- and chlorobenzene, the rate of dissociation following excitation at 266 nm in the gas phase increased with increasing mass of the halogen atom. LÄS MER

  3. 2. Atomic and Molecular Dynamics Probed by Intense Extreme Ultraviolet Attosecond Pulses

    Författare :Jasper Peschel; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Attosecond science; Ultrafast phenomena; High-order Harmonics Generation; Free Electron Lasers; Photoionization; Photodissociation; Fysicumarkivet A:2021:Peschel;

    Sammanfattning : This thesis work was aimed to investigate dynamical processes in atoms and molecules on ultrafast time scales initiated by absorption of light in the extreme ultraviolet (XUV) regime. In particular, photoionization and photodissociation have been studied using pump-probe techniques involving ultrafast laser pulses. LÄS MER

  4. 3. Ultrafast dynamics of small quantum systems studied using electron-ion coincidence spectroscopy

    Författare :Smita Ganguly; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; coincidence spectroscopy; photodissociation dynamics; fragmentation reaction; MOLECULAR-BEAM; Cluster fission; Astrochemistry; Carbon dioxide CO2 ; ; Adamantane;

    Sammanfattning : Studying how small quantum systems, like molecules and clusters, interact with X-rays is crucial to understanding the ultrafast processes that occur in nature on incredibly short timescales, ranging from femtoseconds to picoseconds. X-rays excite small quantum systems to unstable core hole states, leading to a cascade of phenomena, including Auger decay, nuclear rearrangement, and dissociation. LÄS MER

  5. 4. Investigation of Ultrafast Molecular Dynamics via Covariance Mapping : A Tool for Intense XUV Light Sources

    Författare :Jan Lahl; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Covariance; Ultrafast; High-order harmonic generation; Extreme Ultraviolet; Pump probe; FLASH; Velocity map imaging; wavefront; FEL; photodissociation; Coulomb explosion; Fysicumarkivet A:2019:Lahl;

    Sammanfattning : The study of molecular dynamics involves observations of the motion of nuclei and electrons. While nuclear motion is usually on the picosecond or femtosecond timescale, attosecond precision is necessary to directly observe the motion of electrons. LÄS MER

  7. 5. A theoretical perspective on photoinduced reactions - based on quantum chemical models and non-adiabatic molecular dynamics

    Författare :Sambit Das; Michael Odelius; Mårten Ahlquist; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Non-adiabatic dynamics; Molecular dynamics; Surface hopping; TDDFT; X-ray absorption spectroscopy; kemisk fysik; Chemical Physics;

    Sammanfattning : The broad range of applications for photochemical reactions is the result of light-matter interaction at the electronic level. The diverse application of photochemistry in various fields, including photovoltaic materials, molecular switches, and biological systems are due to electronic and structural transformations induced by photoexcitation as well as molecular alteration due to electron and charge transfer. LÄS MER