Citation
Melius, Carl Frederick (1973) I. A theoretical investigation of the charge transfer process in alkaliatom alkaliion collisions. II. Ab initio effective potentials for use in molecular calculations. Dissertation (Ph.D.), California Institute of Technology. http://resolver.caltech.edu/CaltechTHESIS:11202009152551437
Abstract
PART I. The charge transfer processes occurring in collisions of alkali atoms with alkali ions have been studied theoretically using the molecular wavefunction approach. In Part A, we discuss the coupling process between electronic states as exemplified in collisions of Li + Na^+ and Na + Li^+. We find that the total transition process can be decomposed into a succession of simple twostate transition processes. The ΣΣ twostate process can be described by a threestep process involving a coupling region, an uncoupled phase changing region, and a decoupling region. On the other hand, in the molecular wavefunction formulation, the Σ II twostate transition involves a continuous coupling process. The resulting transition probabilities for ΣII coupling differs from Σ Σ coupling leading to different cross sections. In Part B, the molecular wavefunction approach is used to calculate the charge transfer cross sections of alkaliatoms and alkaliions involving Li, Na, and K. PART II. We have investigated the method of effective potentials in replacing the core electrons in molecular calculations. The effective potential method has been formulated in a way which will simplify computations while preserving ab initio quality results. The effective potential is expressed in an analytic form which represents the actual ab initio nonlocal potential (as defined by the matrix elements for a given basis set). Furthermore, this analytic form permits efficient computations of the effective potential integrals by incorporating the properties of Gaussian basis functions. To minimize the number of basis functions required in the molecular calculations, we define a new ab initio effective potential derived from a modified IMF orbital whose core character has been removed. The effective potential method as formulated becomes a very strong but reliable tool in attempting calculations on very large molecules.
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): 

Thesis Committee: 

Defense Date:  13 November 1972 
Record Number:  CaltechTHESIS:11202009152551437 
Persistent URL:  http://resolver.caltech.edu/CaltechTHESIS:11202009152551437 
Default Usage Policy:  No commercial reproduction, distribution, display or performance rights in this work are provided. 
ID Code:  5395 
Collection:  CaltechTHESIS 
Deposited By:  Tony Diaz 
Deposited On:  01 Dec 2009 18:35 
Last Modified:  26 Dec 2012 03:19 
Thesis Files

PDF
 Final Version
See Usage Policy. 5Mb 
Repository Staff Only: item control page