الفهرس 
Absorption of light by moleculesOnly 14 pages are availabe for public view
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Abstract
The present thesis includes three chapters
CHAPTER ONE: Introduction
CHAPTER TWO: Experimental
CHAPTER THREE: results and discussion.
CHAPTER ONE: Introduction
This chapter includes the phenomenon of fluorescence, effect of
pH on fluorescence spectra, solvent effect on fluorescence
spectra and quantum yields of the fluorescence molecules,
quenching of fluorescence and recent literature survey.
CHAPTER TWO: Experimental
This chapter contains information on the materials chemicals,
1,1 ’-2,2’- binaphthol, solvents and reagents. ApparatUs (UV
visible spectrophotometer, spectrofluorophotometer and
photostability setup used as well as the method of statistical
analysis and data presentation.
CHAPTER THREE: Results and Discussion.
This chapter includes the results and discussion.
1- Study of the effect of pH on the absorption and emission
spectra of 1,1 ’-2,2’- binaphthol which was carried out in
phosphate buffer solution. The obtained pKa and pKa* were
10.9 and 6.8, respectively. It is concluded that light absorption
by 1,1 ’-2,2’- binaphthol results in increasing in proton
transfer. This compound under investigation becomes acid in
the excited state.
2- Study of the solvent effect on the absorption and emission
spectra of 1,1 ’-2,2’- binaphthol are sensitive to the solvent
properties. Red shift for the absorption and fluorescence bands were observed. The shift increases m order of
increasing the polarity and acidity parameter.
- Study of photostability: the efeect ofirriadiationon 1,1’-2,2’ binaphthol in different media
(pH3.3,11.4 and H20) causes transformation of 1,1’-2,2’- binaphthol and produces new compounds such
as binaphthaquinone, some binapthols dimers and polymers.
- Study of fluorescence quenching of 1,1’-2,2’- binaphthol by solvent mixture of water I 1,4
dioxane forming nonfluorescencent exciplexes.
- Study of fluorescence quenching of 1,1’-2,2’- binaphthol binaphthol by FeC13, FeCh,
CuCh and AgN03 forming non fluorescent exciplexes.
We conclude the following:
The study of solvent effect on 1,1’-2,2’ binaphthol shows large effect of solvent polarity on the
fluorescence spectra. The
compound can thus be used as solvent polarity indicator.
The value ofpka 10.9 and value ofpka* is 6.8 indicating that 1,1’-2,2’ binaphthol tends to lose a
proton in the excited state.
Photostability studies indicate phototransformation of
1,1’-2,2’- binaphthol in acidic and neutral media with some
degradation products in the basic medium,similar to that obtained in case of naphthols.
Quenching of fluorescence of 1,1’-2,2’ binaphthol by different metal ions indicates that as the
size of the quencher ion decreases and as its charge increases the formation constant of the formed
complex increases.