A Caltech Library Service

Dynamics of Rotationally Resolved Multiphoton Ionization Processes in Molecules


Rudolph, Henrik (1989) Dynamics of Rotationally Resolved Multiphoton Ionization Processes in Molecules. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/981t-6997.


This dissertation presents the results of studies of several rotationally-resolved resonance enhanced multiphoton ionization (REMPI) processes in some simple molecular systems. The objective of these studies is to quantitatively identify the underlying dynamics of this highly state-specific process which utilizes the narrow bandwidth radiation of a laser to ionize a molecule by first preparing an excited state via multiphoton absorption and subsequently ionizing that state before it can decay. Coupled with high-resolution photoelectron spectroscopy, REMPI is clearly an important probe of molecular excited states and their photoioniza tion dynamics.

A key feature of our studies is that they are carried out using accurate Hartree-Fock orbitals to describe the photoelectron orbitals of the molecular ions. The use of such photoelectron orbitals is important in rotationally-resolved studies where the angular momentum coupling in the photoelectron orbital plays a significant role in the photoionization dynamics. In these studies the Hartree-Fock molecular molecular photoelectron orbitals are obtained by numerical solution of a Lippmann-Schwinger integral equation.

Studies reported here include investigations of (i) ionic rotational branching ratios and their energy dependence for REMPI via the A2Σ+(3sσ) and D2Σ+(3pσ)states of NO, (ii) the influence of angular momentum constraints on branching ratios at low photoelectron energies for REMPI via low-J levels of the resonant intermediate state, (iii) the strong dependence of photoelectron angular distributions on final ionic rotational state and on the alignment in REMPI of the A2Σ+ state of NO, (iv) vibrational state dependence of ionic rotational branching ratios arising from rapid orbital evolution in resonant states (E'2Σ+(3pσ) of CH), (v) the influence of rovibronic interactions on the rotational branching ratios seen in REMPI via the D2Σ+(3pσ) state of NO, and (vi) effects of laser intensity on the photoionization dynamics of REMPI.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Chemistry
Degree Grantor:California Institute of Technology
Division:Chemistry and Chemical Engineering
Major Option:Chemistry
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • McKoy, Basil Vincent
Thesis Committee:
  • Zewail, Ahmed H. (chair)
  • McKoy, Basil Vincent
  • Bercaw, John E.
  • Okumura, Mitchio
Defense Date:15 May 1989
Record Number:CaltechTHESIS:08272013-104333878
Persistent URL:
Related URLs:
URLURL TypeDescription adapted for Chapter 1. adapted for Chapter 2. adapted for Chapter 3. adapted for Chapter 4. adapted for Chapter 5. adapted for Chapter 6. adapted for Chapter 7. adapted for Chapter 8. adapted for Chapter 9.
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7947
Deposited On:27 Aug 2013 18:19
Last Modified:20 Oct 2021 00:02

Thesis Files

PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page