High Pressure Study of Viscosity Effects on the Luminescence of Some S-Tetracyanobenzene Eda Complexes
Thomas, Michele Moisio
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/69725
Description
Title
High Pressure Study of Viscosity Effects on the Luminescence of Some S-Tetracyanobenzene Eda Complexes
Author(s)
Thomas, Michele Moisio
Issue Date
1981
Department of Study
Chemical Engineering
Discipline
Chemical Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Chemistry, Physical
Abstract
High pressure fluorescence studies from 0 - 10 kilobars have been performed on electron donor-acceptor (EDA) complexes of s-tetracyanobenzene (TCNB) with a series of aromatic hydrocarbons. Four solvents were used, 2,2,4,4,6,8,8-heptamethylnonane (HMN), methylcyclohexane (MCH), 2,6,10,14-tetramethylpentadecane (TMPD), and a mixture of MCH and HMN. A viscosity range from 0.006 to 10,000 poise was covered at two temperatures, 0(DEGREES)C and 25(DEGREES)C. As pressure (viscosity) increased the fluorescence spectrum shifted from one dominated by emission from the equilibrium (EQ) excited singlet state to one dominated by Franck-Condon (FC) singlet emission. Lifetime measurements for the complexes of o-xylene and p-xylene with TCNB yielded the two radiative rates (k(,EQ) and k(,FC)) as well as the rate of relaxation from FC to the EQ excited state (k(,RE)). k(,RE) was found to correlate well with viscosity and to be independent of temperature at constant viscosity, indicating that the relaxation process is diffusion controlled.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.