الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
I-In the first chapter a literature survey of the previous studies on azo compounds
and their complexes with different metal ions is given. This survey includes
spectrophotometric, conductometric and potentiometric studies on azo
compounds and their chelates. It includes also the use of some azo compounds
as analytical reagents for detection and determination of some transition metal
ions spectrophotometrically.
2-The experimental part ( Chapter II ) includes the preparation of the azo
compounds under investigation. It comprises also information about the
instruments used for spectrophotometric, potentiometric, conductometric, ir,
’Fl-nmr, magnetism as well as thermal analysis measurements.
3-Chapter III includes the results and discussion and consisting of four parts.
(A)The first part includes the studies of the electronic absorption spectra of
the free ligands in the uv and visible regions using ethanol as solvent. The
bands exhibited in the uv spectra of the compounds are assigned
according to the nature of the band and spectral behaviour in different
organic solvent. The band A is due to ( JLa+--- IA) and B is due to
( ILb +--- IA) transition of phenyl ring, respectively. On the otherhand,
the band Cat 350 - 450 nm ranges represents a charge transfer transition
through the molecule. The position of the CT band in different organic
solvents of protic and aprotic nature is discussed in terms of different
emperical solvent polarity parameters and macroscopic solvent polaril}’
Su~
parameters.
The electronic absorption spectra of the free ligands are studied in
ethanolic buffer solution of different pH values and their iOnization
constants are evaluated. Also the ir and IH_nmr spectra of the compounds
under investigation are studied and the different functional groups are
assigned like Yc”o, YN”N,YCHand YOH.O~ the other hand, the ’H-runr
spectra for different types of hydrogen protones expected for the
compounds under study (I-VI) can be numerated, detennined and
correlated to the molecular structure of the compounds.
(B) This part is concerned with the studies in solutions of complexes formed
between azo compoWlds and some transition metal ions (Cu2’, Ag+, and
Atr’”), The studies include spectrophotometric, conductometric and
potentiometric techniques. TIle stoichiometry and stabilil}’ constants of
metal complexes are also evaluated from spectrophotometric methods
namely the molar ratio and continuous variaJion methods. The optimum
conditions for the complex fonnation are investigated. Universal buffer of
40% (v/v) ethanol was found to be the best medium for
spectropbotometric studies. Optimum pH values, snilable wavelength as
well as sequence of addition were also studied. from conductometric
measurements the stoichiometry of different complexes is obtained.
Potentiometric titrations of azo compoWlds with Cu2+, Ag+ and Au”
Lr~ 120
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ionsare Perfonned in a medium ofperchloric acid and sodium perchlorate.
The proton-ligands stability constants log KH are detennined as well as
the fonnation constants of complexes ( log KM
). The results obtained
indicate that a satisfactory agreement is observed between stability
Summary
constant values evaluated using spectrophotometeric and potentiometric
methods.
(C) Part C of chapter III includes studies of the solid chelates which contain
elemental analysis molar conductivity measurements, TGA, OTA, ir,
magnetic measurements, and electronic absorption spectra. The molar
conductance of complexes in OW shows that these chelates are
electrolytes in nature. The chemical formula of solid chelates were
detennined using the data obtained from therinal methods ofanalysis
(TGA and OTA) as well as dehydration and elemental analysis. The ir
spectra of metal chelates are studied and compared with those of the free
ligands indicating that the coordinate and covalent bonds occurs through
the oxygen atoms of carbonyl groups and the metal ions. The ir spectra
of the metal chelates exhibit a very broad band around 3300 em” which
is due to the water molecule coordinated to the central metal ions. The
magnetic susceptibilities of some representative solid Cu2• -chelates are
measured using the GOUY method, from which the magnetic moments
(J.lerr) and· the number of unpaired d-electron in the Cu2• -ion are
detennined. The stereochemistry of these chelates were then detected
2!121 ~
-””’----------~~~---
Summary
using Paulling’s theory. The absorption spectra of some selected solid
chelates are studied in both DrvtF and nujol mull. The variation of the
position of the CT band in the two media indicates the variation of the
environment of the central metal ion in DMF solution than in the solid
stat•e. The CT band due to L ---.. M or M ----.. L transition appears
at longer or shorter wavelength to CT band of the free ligand confirming
the interaction between the metal ions and the ligands.
(D)The part 0 include the analytical microdetennination of the metal
ions(Cu
2
+. Ag” and Au3+) with azo compounds under investigation using
the spectrophotometric techniques (Beer’s and Ringbom methods). It
includes also the effect of ligands concentration, the effect of foreign ions
on the absorbance and also the use of such compound in the microdetennination
of metal ions under consideration.