A SPECTROPHOTOMETRIC AND
SPECTROFLUOROMETRIC STUDY OF
MORIN COMPLEXES 0F TRIPOSITIVE

CERlUM, NEODYMIUM, PRASEODYMIUM,
SAMAfllUM, TERBIUM AND IHUUUM

Thesis for the Degree of M. 8‘.
MICHEGAN STATE UNIVERSITY
MARGARET E. TIERNEY
1968

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THESIS

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ABSTRACT

A SPECTROPHOTOMETRIC AND SPECTROFLUOROMETRIC
STUDY OF MORIN COMPLEXES OF TRIPOSITIVE
CERIUM, NEODYMIUM, PRASEODYMIUM, SAMARIUM,
TERBIUM AND THULIUM

by Margaret E. Tierney

Morin forms complexes with cerium (III), neodymium
(III), praseodymium (III), samarium (III), terbium (III) and
thulium (III). The effect of pH on the absorbance of these
complexes and the nature of these complexes in 50 percent
dioxane-SO percent water solutions were investigated.

bknfix1formsl¢2 complexes (lanthanide (III):morin) with
these rare earth ions at pH 5.0 as determined by Job's
method of continuous variations and confirmed by Harvey and
Manning's lepe-ratio method. The values of the equilibrium
ratios for these complexes are 0.83, 4.5, 2.7, 7.9, 0.73
and 2.5 for cerium, neodymium, praseodymium, samarium,
terbium and thulium, respectively.

The complexes fluoresce only slightly more_than morin
when exposed to 365, 456 mu- or there absorption maximum wave-
length radiation, while the complexes of lanthanum, gadolin-
ium and lutetium flouresce significantly under these

conditions.

Margaret E. Tierney

The absorption band peak of morin occurs at 356 mu.,
while the complex absorption band peaks for cerium and
praseodymium, neodymium, samarium, terbium, and thulium
occur at 413, 414, 415, 417, and 423 mu., reSpectively.

A single isoabsorptive point exists in the absorption
spectra of each of the complexes. The isoabsorptive point
occurs at approximately 377 mu.

The absorbances for the complexes change linearly
with change in lanthanide (III) concentration over the
approximate concentration range, 0 to 2.3 x 10"5 M., in

the presence of excess morin, 1.32 x 10‘4 M.

A SPECTROPHOTOMETRIC AND SPECTROFLUOROMETRIC
STUDY OF MORIN COMPLEXES OF TRIPOSITIVE
CERIUM, NEODYMIUM, PRASEODYMIUM, SAMARIUM,

TERBIUM AND THULIUM

By yf

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. 2%“

Margaret E. Tierney

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Chemistry

1968

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ACKNOWLEDGEMENT

The author wishes to express her appreciation
to Dr. Andrew Timnick for guidance and encouragement
throughout this investigation and to Mr. John F.

Holland for construction of the fluorescence instru-

ment.

***************

ii

VITA

Name: Margaret E. Tierney
Born: Sept. 21, 1943 in New Britain, Connecticut

Academic Career: Regina High School, Hyattsville,
Maryland (1957-1961)

Chestnut Hill College, Philadelphia,
Pennsylvania (1961-1965)

Michigan State University,
East Lansing, Michigan
(1965- )

Degree Held: B. S. Chestnut Hill College (1965)

iii

TABLE

INTRODUCTION . . . . .
HISTORICAL . . . . . .
EXPERIMENTAL . . . . .

Instrumentation .
Reagents. . . . .

OF CONTENTS

Preparation of Reagent Solutions.

Experimental Procedures

Method of Sample Preparation
Instrumental Measurements.
Nature of the Complex.

DISCUSSION OF RESULTS.

General . . . . .

Effect of pH on Absorbance.
Nature of the Complex .
Equilibrium Ratios of the Complexes

SUMMARY AND CONCLUSIONS.

LITERATURE CITED . . .

APPENDIX . . . . . . .

iv

Page

11

12
14
15
17
17
18
18

21
22
37
37
44
61
64

74

LIST OF FIGURES

Figure Page
1. Block diagram of spectrofluorometer. . . . . . . 13

2. Absorption Spectra of morin and the complexes
of morin with samarium (III) and praseodymium
(III) in 50—50 DW at pH 5.0. . . . . . . . . . . 25

3. Absorption Spectra of the complexes of morin
with neodymium (III) and thulium (III) in 50-50
DW at pH 5.0 O O O O O O O O C O O O O O O 0 O O 24

4. Absorption spectra of the complexes of morin
with terbium (III) and cerium (III) in 50-50 DW
at pH 5.0. . . . . . . . . . . . . . . . . . . . 25

5. Effect of pH on the absorbance of the complexes
of morin with samarium (III) and praseodymium
(III) in 50-50 DW. 0 o o o o o o o o o o o o o o 26

6. Effect of pH on the absorbance of the complexes
of morin with neodymium (III) and thulium (III)
in 50-50 DW. . . . . . . . . . . . . . . . . . . 27

7. Effect of pH on the absorbance of the complexes
of morin with terbium (III) and cerium (III) in
50—50 DW . . . . . . . . . . . . . . . . . . . . 28

8. Fluorescence spectra of the complex of morin
with lanthanum (III) in 50-50 DW . . . . . . . . 29

9. Fluorescence Spectra of the complex of morin
with samarium (III) in 50-50 DW. . . . . . . . . 30

10. Fluorescence spectra of the complex of morin
with praseodymium (III) in 50-50 DW. . . . . . . 31

11. Fluorescence spectra of the complex of morin
with neodymium (III) in 50-50 DW . . . . . . . . 32

12. Fluorescence spectra of the complex of morin
with thulium (III) in 50-50 DW . . . . . . . . . 33

LIST OF FIGURES - Continued

Figure

13.

14.

15.

16.

17.

18.

19.

20.

21.

22.

23.

24.

25.

26.

Fluorescence Spectra of the complex of morin
with terbium (III) in 50-50 DW. . . . . . . . .

Fluorescence Spectra of the complex of morin
with cerium (III) in 50-50 DW . . . . . . . . .

Fluorescence Spectra of morin in 50-50 DW . . .

Spectrophotometric isoabsorptive point for the
complex of morin with samarium (III). . . . . .

Spectrophotometric isoabsorptive point for the
complex of morin with praseodymium (III). . . .

Spectrophotometric isoabsorptive point for the
complex of morin with neodymium (III) . . . . .

Spectrophotometric isoabsorptive point for the
complex of morin with thulium (III) . . . . . .

Spectrophotometric isoabsorptive point for the
complex of morin with terbium (III) . . . . . .

Spectrophotometric isoabsorptive point for the
complex of morin with cerium (III). . . . . . .

Determination of the composition of the samar-
ium (III)-morin complex in 50-50 DW at pH 5.0
by method of continuous variations. . . . . . .

Determination of the composition of the praseo-
dymium (III)-morin complex in 50-50 DW at pH
5.0 by method of continuous variations. . . . .

Determination of the composition of the neodym-
ium (III)-morin complex in 50-50 DW at pH 5.0
by method of continuous variations. . . . . . .

Determination of the composition of the thulium
(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations . . . . . . . .

Determination of the composition of the terbium

(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations . . . . . . . .

vi

Page

34

35
36

38

39

40

41

42

43

45

46

47

48

49

LIST OF FIGURES - Continued

Figure

27.

28.

29.

30.

31.-

32.

Page

Determination of the composition of the cerium
(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations . . . . . . . . 50

Determination of the composition of the .samar-
ium (III)-morin complex in 50-50 DW at pH 5.0
by lepe ratio method . . . . . . . . . . . . . 51

Determination of the composition of the praseo-
dymium (III)-morin complex in 50-50 DW at pH
5.0 by slope ratio method . . . . . . . . . . . 52

Determination of the composition of the neodym-
ium (III)—morin complex in 50-50 DW at pH 5.0
by lepe ratio method . . . . . . . . . . . . . 53

Determination of the composition of the thulium
(III)-morin complex in 50-50 DW at pH 5.0 by
slope ratio method. . . . . . . . . . . . . . . 54

Variation in absorption of terbium (III) and

cerium (III)-morin complexes with variation in
lanthanide (III) ion concentration in presence

of large excess of morin. . . . . . . . . . . . 55

vii

INTRODUCT ION

The rare earths or lanthanides have been very difficult
to separate because of their great similarities in chemical
prOperties under usual conditions. These great similarities
are due to the shielded nature of the 4f subshell which is
filled with electrons as the lanthanide series progresses
from lanthanum to lutetium.

Before 1945 these elements were frequently determined
as a group with a nonselective precipitant. The oxalate
method was the most extensively studied. The lanthanides
were precipitated as their oxalates with oxalic acid (1),
ammonium oxalate (2), dimethyl oxalate (3), or diethyl
oxalate (4). Occasionally they were precipitated as fluorides
or hydrous oxides.

Nonselective titrimetric methods have been used to
determine the rare earth elements as a group. Ethylenedi-
aminetetraacetic acid (EDTA) is the most frequently used
titrant. Many indicators have been developed for this
method (5-15). Complexone III (16—18) and Trilon B (19-22)
are also common titrating agents.

Better methods than the classical methods of fractional
crystallization and fractional precipitation have been de-
velOped for separating the rare earths. Some separations
are effected by oxidation or reduction to anomalous oxida-
tion states (states other than tripositive). Another method

is liquid-liquid extraction, often with tributyl phOSphate.

Extraction separations have been enhanced using reagents
that form complexes with the rare earths. The most modern
method is ion exchange chromatography. Ion exchange
separations have also been sharpened using complexing agents
such as morin (23), EDTA, (24-26) and 8-hydroxyquinoline
(27). Several books summarize the advances in separation of
the lanthanides (28-30). With more abundant quantities of
high purity rare earths available, it is possible to study
more effectively the individual elements and determine
trends in the properties of the lanthanide series.

The fluorescence Spectra of rare earth compounds have
been known since the 1930's. However, analytical applica-
tions have been few since the fluorescence spectra are weak.
In qualitative detection tests, only lanthanum (III),
gadolinium (III) and lutetium (III) formed fluorescent com-
plexes with morin (2',4':3,5,7-pentahydroxyflavone) (31).
The other lanthanide (III)-morin complexes did not fluoresce
due to internal quenching caused by intramolecular energy
transfer.

There are two methods of SpectrOphotometric analysis
for the rare earth elements. One method utilizes the band
absorption Spectra of the colored ions. The spectra of
aqueous solutions are complex, extending from the ultra-
violet to the infrared region. The spectra of the lan-
thanide (III) perchlorates (32-38), chlorides (33,34,38-43),

nitrates (33,44,45) and acetates (33) are well known.

The molar absorptivities of the lanthanide (III) ions are
low, ranging from approximately one to ten (29). Thus the
absorption bands are not applicable for the determination
of micro quantities of lanthanides.

The second Spectrophotometric method for lanthanide
analysis utilizes the formation of intensely absorbing com-
plexes. The formation of lanthanide (III) complexes in
solution leads to modifications in the ligand absorption
Spectra, since the complexes generally absorb light at dif—
ferent wavelengths than the chelating ligands.

A variety of chromOphoric agents are available for
determination of the rare earths. These elements have been
determined using Xylenol Orange (46-54), Alizarin Red S
(55-58), 3-nitroalizarin (59), salicylic acid derivatives
(60-63), Aluminon (57,63-65), naphthazarin (66), oxidized
Haematoxylin (67), Chrome Azurol S (57,68-70), Pyrocatechol
Blue (71), Methylthymol Blue (72-75), Thymolphthalexon (74),
Erichrome Black T (75), Naphthyl azoxine S (76), Chromotrope
B (57,77), Pontacyl Violet (78), Arsenazo (79-82), PAR (83),
Stilbazo (84), dinitropyrylazo (85), 5,7-dibromohydroxy-
quinoline (86) and Thoron (57). These elements have also
been determined using EDTA and several related acetic acid
derivatives (87-98). Morin has been used for spectrophoto-
metric and spectrofluorometric determination of the rare

earths and other elements (99-103).

The purpose of this investigation is to extend the
studies of the complexation reactions between morin and
lanthanide (III) ions in 50-50 dioxane-water begun by Fleck
(99),‘Weiler (100) and Van Eenenaam (101). A study was
undertaken to establish light absorption and fluorescence
characteristics of the complexes formed between morin and
cerium, neodymium, praseodymium, samarium, terbium and

thulium.

HISTORICAL

Several books have been published concerning fluores-
cence phenomena. ,Pringsheim discussed the theoretical
aSpectS of fluorescence, including a chapter on the lanth—
anide elements (104). Fluorescence is also discussed by
Bowen and Wokes (105). Hercules has edited a book on the
topic (106). In addition, C. E. White reviews both organic
and inorganic applications of fluorometric analysis in
"Analytical Chemistry" (107,108). Poluektov and Kononenko
also reviewed the fluorescence of rare earth chelates (109).
Multitudinous references are cited in these review articles.

The lanthanides form many complexes with 8-diketones
(110-119). Prominent among these complexes are those with
thenoyltrifluoroacetone, benzoyltrifluoroacetone and di-
benzoylmethane. Major investigations of these complexes
have been performed by Crosby and Whan (120,121) and
Kononenko and Poluektov (122-124). Crosby and Whan propose
the theory that the triplet state of the complex must be
above the resonance level of the lanthanide for fluorescence
to occur. Many of these complexes do fluoresce and this
property has made them important in the development of
lasers (125-129).

Fluorescence is observed for morin complexes with lan-
thanum (III), gadolinium (III) and lutetium (III) (31,99—
101,130). For the other lanthanide-morin complexes there
is considerably less, if any, fluorescence.

Katyal has reviewed the use of flavones as analytical

reagents (103). The complex of morin with gallium has been

studied by Akhmedli and Bashirov (131) and by Akhmedli and
Glushchenko (132). Dombi and Kozema have studied the re—
action of morin with aluminum (133,134). Mary Fletcher
conducted a fluorometric investigation of the beryllium-

morin system (135). Nowicka-Jankowska (136) and his co-
workers have reported 1:1 complexes of morin with praseodymium
(III), gadolinium (III), yttrium (III) and holmium (III).

Milkey and Fletcher (102)conducted an investigation of
the thorium (IV)-morin complex in Slightly acidic ethanol-
water mixtures. Their investigation and the work of Fleck
(99), Weiler (100) and Van Eenanaam (101) was used as a
pattern for this study.

A number of methods still widely used to determine the
formulae and stability constants of complexes were originally
designed for the case in which only one complex is formed.
The method of continuous variations was first applied to the
formation of complexes in solution by Job (137). Vosburg
and Cooper (138) and Katzin and Gebert (139) have extended
Job's method to systems in which more than one complex is
formed.

Bent and French (140) determined the composition and
dissociation constant of ferric thiocyanate by varying the
concentration of thiocyanate with a constant concentration
of iron and then varying the concentration of iron with a
constant concentration of thiocyanate. The stability

constant is obtained by analyzing the interrelationship

between the logarithm of the absorbance and the logarithm
of the total thiocyanate ion concentration. The logarithm
of the total thiocyanate concentration was plotted against
the lograithm of the absorbance, constants having been

added to both axes to give a line intersecting the origin.

The mole-ratio method applicable to very slightly
dissociated complexes is attributed to Yoe and Jones (141).
The absorbance is plotted as a function of the ratio of
total concentration of anion to cation. A break in the
curve is obtained at the stoichiometric ratio of anion to
cation.

Equimolar solutions have been employed by several
scientists to determine stability constants. Hagenmuller
(142,143) developed a method using equimolar solutions that
is restricted to 1:1 complexes. A series of mixtures of the
two substances capable of forming complexes is prepared and
an additive physical property determined. The position of
the maximum of the curve representing the differences be-
tween the observed values and those which correspond to the
rule of mixtures indicates the mole ratio of the two origi-
nal substances in the compound. The method of Betts and
Michels (144) is similar to Hagenmuller's, but does not
employ equimolar solutions. Shaeppi and Treadwell (145) also
developed a method using equimolar solutions. Schwarzenbach
(146) developed the restrictions for their method (145) when

a 1:1 complex is formed.

10

Another method of establishing the composition of com-
plexes is the Slope-ratio method of Harvey and Manning (147).
The absorbance of the complex is plotted against varying
concentrations of ligand holding metal ion concentration
constant, and against varying concentrations of metal ion
holding ligand concentration constant. The SIOpe of the line
obtained in the presence of excess metal ion represents the
change in absorbance per mole of ligand. The slope of the
line obtained in the presence of excess ligand represents the
change in absorbance per mole of metal ion. The ratio of the
slope of the line representing the change per mole of morin
to the slope of the line representing the change per mole of
metal ion indicates the ratio of metal ion to ligand in the

complex.

EXPERIMENTAL

11

12

Instrumentation

 

The spectrofluorometer used for this research is a

double monochromator instrument designed and constructed

by Mr. J. Holland of Michigan State University. Figure 1

shows a block diagram of the instrument which illustrates the

excitation and fluorescent emission light paths. The

spectrofluorometer consists of the following components:

1.

6.

An Osram XBO-150 xenon arc lamp ultraviolet source
powered by a Sola model 67-10—109 power supply

with the lamp mounted in a standard Bausch and

Lomb housing and cooled by an air circulating fan;
Bausch and Lomb model 33-86-45-58 grating mono-
chromators with both gratings blazed at 3000 3.;

A custom made brass cell holder, with provision

for constant temperature regulation, to hold
Pyrocell clear-window 10 mm. silica cells made
especially for fluorometry;

An RCA 1P28 photomultiplier tube mounted in a light-
tight housing attached to the emission monochromator
as illustrated;

The detector electronics system consisting of a
Philbrick P25A operational amplifier used in a
follower mode and an Analogue Device #210 operational
amplifier used as a unity gain filter amplifier;

A Sargent SR recorder.

13

 

 

 

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Photomultiplier '
Tube ‘-‘-_““-§.:EE
I'

 

 

 

Amplifier &
Power Supply

 

 

 

 

Recorder

 

 

 

 

 

Bausch & Lomb
Grating Monochromator

 

 

 

 

 

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W

Bausch & Lomb
Grating Monochromator

‘Cell compartment

Xenon Arc Source
4 I
K“
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L-fi

Arc Power Supply

 

 

 

Figure 1. Block diagram of Spectrofluorometer.

14

Cary Model 14 recording spectrophotometer was used for
all absorption measurements. A matched pair of Beckman
standard blue silica cells having a pathlength of 1.000.i
0.005 cm. was used for these measurements.

A Sargent constant temperature bath employing a Princo-
Magna-Set mercury temperature control was used to maintain
the temperature of solutions at 25.0 i 0.020C.

A Beckman Model 76 expanded scale pH meter equipped
with a glass-saturated calomel microelectrode pair or with
a micro-combination electrode was used for all pH measure-
ments. The instrument was calibrated with Beckman or Fisher

Certified pH 4 buffer.

Reagents

Ammonium Hydroxide
Baker's Analyzed Reagent Grade, assay 29.9% as NH3,
distilled and stored in a polyethylene bottle equipped with

an ascarite protection bulb.

Cerous Perchlorate (Hydrated)

G. Frederick Smith's Reagent Grade.

2',7'-Dichlorofluorescein

Eastman Kodak White Label.

p-Dioxane

Fisher Certified Grade.

Eastman Kodak White Label.

15

Lanthanum Oxide
Optical Grade, Heavy Minerals Company, Chattanooga,

Tennessee.

Morin Dihydrate

Dr. Theodor Schuchardt, Munich, Germany.

Neodymium, Praseodymium, Samarium, Terbium and
Thulium Oxides

 

Michigan Chemical Corporation , St. Louis, Michigan.

Perchloric Acid
Baker and Adamson's Reagent Grade, 70-72%.

Mallinckrodt's Reagent Grade, 70—72%.
Preparation of Reagent Solutions

Ammonium Hydroxide
The ammonium hydroxide used for pH adjustment was about

0.1 M and was prepared from the distilled material.

Dichlorofluorescein
A 0.4 7 per ml. solution in 4% ethanol was prepared
by dilution of a stock solution prepared by dissolving a

weighed quantity of the reagent in 95% ethanol.

Dioxane

A modification of the procedure of Hess and Frahm (148)
develOped by Fieser (149) was used to purify certified
grade dioxane. A mixture of 4 l. of dioxane, 400 ml. of

distilled water, and 54 ml. of concentrated hydrochloric

16

acid was refluxed for 12 hours, during which time a Slow
stream of nitrogen was bubbled through the solution to
sweep out aldehydes. The solution was cooled, potassium
hydroxide pellets were added Slowly with mixing until the
solution became saturated and a second layer formed. The
dioxane was decanted and treated with additional potassium
hydroxide. The partially dried dioxane was then decanted
into an amber screw-cap bottle containing a layer of an-
hydrous calcium chloride. After standing at least overnight,
the dioxane was filtered into a 5 liter round-bottom flask,
refluxed over calcium hydride for 12 hours and distilled.
A 50 ml. forecut and about 300 ml. heel were discarded.”
The product distilled at 100.1 0.50C. It was stored in

amber glass-stoppered bottles.

Lanthanide Oxides

Portions of the various oxides were weighed and dis-
solved in a minimum amount of perchloric acid. For Ce(III),
a portion of the perchlorate was weighed and dissolved in
a minimum amount of perchloric acid. The above solutions
were diluted and aliquots titrated with a 0.0503 M solution
of primary standard disodium ethylenediaminetetraacetate
(150) to the xylenol orange endpoint (87). Aliquots of
these standardized solutions were taken for the preparation
of the working solutions of 10.0, 1.0, 0.1 and 0.01 mg. of

lanthanide (III) ion per ml.

17

Morin
A weighed portion of morin dihydrate reagent was dis-
solved in purified dioxane to produce a solution of

1.655 x 10"3 M morin.

Perchloric Acid

 

The perchloric acid used for pH adjustment was about

0.1 M and was prepared by dilution of the reagent acid.
Experimental Procedures

All experimental work was performed at 25.: 10C. All
solutions were equilibrated in a constant temperature bath
maintained at 25.i 0.02OC for a minimum of one-half hour

before making measurements.

Method of Sample Preparation

The desired volume of morin solution was transferred
into a 25 ml. volumetric flask. Pure dioxane was added to
give a total dioxane volume of 12.5 ml. The desired volume
of lanthanide perchlorate solution was added and then dis-
tilled water until the total volume was 21-22 ml. The
solution was transferred to a 30 ml. beaker where the pH
was adjusted to 5.0 with dilute ammonium hydroxide and/or
perchloric acid. The resulting solution was transferred
back to the 25 ml. flask and the sample diluted to the mark.
The pH of the sample was checked after equilibration in

the thermostated water bath.

18

Instrumental Measurements

Spectrgphotometric Measurements. The instrument was
allowed to warm up for at least 20 minutes to insure instru-
mental stability. The baseline was set to zero with light
passing through solvent solution of 50-50 dioxane and

water at pH 5.0 in both reference and sample beams.

Spectrofluorometric Measurements. To standardize the
instrument the excitation monochromator was set at 335 mu
(one of the strong peaks of dichlorofluorescein), while the
emission monochromator was set at 520 mu. The xenon lamp,
power supply, amplifiers and detector were warmed up for at
least 20 minutes to insure stability. The 0.5 7 per ml.
dichlorofluorescein solution was placed in the cell, the
shutter opened and the instrument adjusted to give a read-
out of 60. The value of 60 was chosen so that a solution
of lanthanum-morin complex at pH 5.0 would yield a fluores-
cence spectrum (Figure 8) of the same magnitude as that
obtained for the same concentration solution in previous
studies employing a different Spectrofluorometer. Instru—
mental readings were recorded as relative fluorescence

intensities.

Nature of the Complex

Isoabsorptive Point. In order to determine the number

 

of complexes formed and whether the reaction is stoichio-

metric, a series of solutions containing 400 7 of morin and

19

amounts of lanthanide (III) varying between 0 and 100 y

per 25 ml. were prepared and adjusted to pH 5.0.

Method of Continuous Variations. Job's method of con-
tinuous variations (137) was employed to determine the
empirical formula of the complex formed. The absorbances
for praseodymium (III) and cerium (III) systems were measured
at 356, 390 and 413 mu, for the neodymium (III) system at
356, 390 and 414 mu, for the samarium (III) system at 356,
390 and 415 mu, for the terbium (III) system at 356, 390
and 417 mu, and the thulium (III) system at 356, 390 and
423 mu. The total concentration of lanthanide (III) ion
and morin was maintained constant at approximately 54 x 10'6 M,
the actual value differing slightly for each lanthanide (III)

ion.

Slope Ratio Method. To confirm the composition of the

 

complexes, the slope-ratio method of Harvey and Manning (147)
was employed. A series of solutions containing lanthanide
(III) ranging in concentration from approximately 0.2 x 10'5
M to 2.3 x 10‘5 M in the presence of a large excess of
morin, 1.32 x 10‘4 M , were prepared. The absorbances of
these solutions, measured at the desired wavelength, were
plotted against the concentration of lanthanide (III) ion,
and the slope of the line determined. A series of solutions
containing morin in the concentration range of approximately

0.6 x 10‘5 M to 5.3 x 10“5 M in the presence of a large

20

excess of lanthanide (III) ion were also prepared. The
absorbances were plotted against the concentration of morin
and the slope of the line determined. The ratio of the
slopes of the two lines was then determined to obtain the

ratio of lanthanide (III) ion to morin in the complex.

DISCUSS ION OF RESULTS

21

22
General

Morin (2',4',3,5,7-pentahydroxyflavone) forms complexes
with cerium, neodymium, praseodymium, samarium, terbium and
thulium. The absorption spectra of morin and the complexes
are Shown in Figures 2-4. The complexing agent has an ab-
sorption peak at 356 mp. 413, 414, 415, 417, and 423 mu. are
the absorption peak wavelengths for the cerium and praseodym-
ium, neodymium, samarium, terbium, and thulium complexes,.
reSpectively.

Figure 8 shows that the lanthanum—morin complex fluores-
ces significantly when eXposed to ultraviolet radiation as
Fleck (99) also observed. Weiler (100) observed fluorescence
from the morin complexes of gadolinium and lutetium. Morin
fluoresces to a Slight extent under the experimental condi-
tions as illustrated in Figure 15. Figures 9-14 Show that
the rare earth complexes under investigation do not fluoresce
much more than morin. These results confirm the observa-
tions of Pollard §£_§l, (31) who ran qualitative tests to
determine whether lanthanide-morin complexes fluoresced
when illuminated with ultraviolet radiation. Van Eenanaam
(101) also demonstrated that the morin complexed dySprosium,
erbium, europium, holmium and ytterbium fluoresced very

weakly.

Absorbance

23

 

 

 

1.00
5 1) 400 y morin
2) Samarium (III)-morin
complex (100 7 Sm+++)
0.90-—— ,r\ 5) Praseodymium (III)-
, 2 morin complex (100 7
I Pr+++)
0.80... /
I \
I \
l \
O.70__ / \
I \
I \
o.eo_—- / \
\
/ \
/ \
O.50+—— / \
\
0.4o_ / ‘
/ \
/ \
t’/ \
0.30r— \
\
\
0.80 __ \
\
\
0.10r——- \
\
|\

 

 

520 540 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.

Figure 2. Absorption Spectra of morin and the complexes
of'morin with samarium (III) and praseodymium (III)
.in 50-50 DW at pH 5.0.

Absorbance

1.00

0.70

0.60)

0.40

0.30

0.20

0.10

0

F

24

 

 

Neodymium (III)-morin

complex (100 V Nd+++)
‘—_— ----- Thulium (III)-morin

complex (100 7 Tm+++)
,___ //_\\

//\
““ / \
’ \
/
._ / \
/’
/ \
I
_/ \
’ \

../

\

\

\
.r__ \
\
"’ \
\
\\
lilllll —4-|

 

 

 

520 340 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.

igure 3. Absorption spectra of the complexes of morin

with neodymium (III) and thulium (III) in 50-50

DW at pH 5.0.

Absorbance

25

 

 

 

 

 

 

 

 

 

1.00

Cerium (III)-morin

complex (100 y Ce+++)
0.90 __. ----- Terbium (III)-morin

complex (100 y Tb+++)
0.80,___

/'
/
/ \
0.70 / \
/ \
O O I
.6 / \
/
/ \
0.50 \
/.
/' \
,/
0.40 / \
’ \

0.50 \

\

\
0.20 \
\
0.10 \
\
. '\
o l l J I l I I \~

 

 

 

320 340 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.

Figure 4. Absorption Spectra of the complexes of morin
with terbium (III) and cerium (III) in 50-50

DW at pH 5.0.

Absorbance

26

 

 

 

 

 

400 y morin and 100 y R+++
. A4 1 5 Sm+++-morin
system
1 00 o A413 Pr+++—morin
' "" system
0.90_-
0.80_—-
0.70_——
0.60)——
0.50_—-
0.40——-
0.30——-
0.20—
0.10——
O | l
0 1 2

 

Figure 5. Effect of pH on the absorbance of the complexes
of morin with samarium (III) and praseodymium
(III) in 50-50 DW.

Absorbance

27

 

 

400 y Morin and 100 7 R+++
o A414 Nd+++-morin system
+++ . '
o A423 Tm -morin system
1.00—
0.90)—
/o——-O--
0.80— O
14.:7
0.70_ ' '
0.60——
O.50‘——
0.40.—
0.50T——
0.20—__
O-lO~——
o J J J J J J J l J J

 

 

 

pH

Figure 6. Effect of pH on the absorbance of the complexes
of morin with neodymium (III) and thulium (III)
in 50-50 DW.

Absorbance

28

 

. +++
400 y Morin and 100 y R
o A417 Tb+++-morin system

-morin system

+++
A413 C8

0

O?
O

 

U1
0

 

 

 

pH

Effect of pH on the absorbance of the complexes
of morin with terbium (III) and cerium (III) in
50—50 DW.

Figure 7.

29

.o.m mm um 3n omuom ca
AHHHV Escmnucma nuw3 :HHOE mo memEoo may mo mnuommm mocmommuosam .m musmflm

.12 SH numcmam>m3

omm 0mm own omm 00m omw Omw OSS CNS
- - J ,o

 

 

 

. J. oe

II! ON

II! on

J, 04

III om

J. 8

J. 2.

 

II! om

“mom
+++mq > oo« H o
+mq > ooe “33H 0 II! cm

“mov
+++mq r 006 H o

 

 

00d

 

AquuequI eoueosexontg

30

.30 omlom SH
AHHHV ESHHMEMm SDHB SHHOE wo xmameoo may no muuommm muomummuosam .m musmam

.12 ca numcmam>m3
00m oem 0mm 00m 00¢ 00¢ oew CNS

 

 

mQOH G
CAHOZ % 00¢ povH 0 II! 0w
P A mav
+++Em 00d H O

 

mnflH C

afluoz % 00¢ omvH 0 ll! 0%

new
++Em ? 00« H 0

 

+

 

 

AquuequI soueosexonta

31

.SD omlom aw AHHHV
EDHEhpommmum nufl3 canoe mo xmamfioo m£u mo muuummm mocmommuosam .0H musmflm

.12 CA numcmam>m3

 

 

 

 

 

 

 

 

 

 

00m 0¢m 0mm 00m 00¢ 00¢ 0¢¢ 0N¢
- . - Jao
06.
o.m me me.
mmflH 0
demo: r 00¢ omvH 0 III 0m:
ma¢
+++um to 0o.“ H o ,
1! 0
INN/[J7 - . q .\ m
0H
0
0.¢ mm ma
0
./ MOGH c
%. mdfi .
+++Hm OOH H

 

 

 

Aqrsuequx soueosexontg

32

Enafimpomc SDAB

.zn omnom :H AHHHV

canoe mo xmamfioo on» mo manommm mocmommHOSHm .HH mnsmflm

.12 CH Sumcmam>m3

 

 

 

 

 

 

00m 0¢m 0mm 00m 00¢ 00¢ 0¢¢ 0 ¢
¢ _ _ L A A o
U l mON
o e
:11 o.m
,0
o.m mm
III m.>
mDMH a
:HHO2 P 00¢ o mowH 0 II. 0.0a
o ¢H¢
+++UZ F 00H H 0
J0/ ‘J #0
o .. J 0.3
0 II! 0.0m
o
\\\\ 0.¢ mm
. D .II! 0.0m...
. O mOGH a
:Huo2 r 00¢ omeH o II. o.o¢
vav
+++UZ P 00d H O

 

 

Aqrsuaqul eoueosexonxg

33

.3D 0mI0m CH

 

 

 

AHHHV EDHHDSB SDHB SHHOE mo memEoo map mo muuommm mocmommnosHm .NH musmflm
.12 SH sumcon>m3
00m 0¢m 0mm 00m 00¢ 00¢ 0.¢ 0 ¢
j A a — \ O
O /.o ‘ 9 ' IIIL OH.
/ O
./ \. l 8
3 men H
o )\ o ,
GHHO2 % 00¢ o- . om¢H 0 II. on
EB a 00H mmvH o
+++ . I Jlfl O
“ ‘ 0 ‘ ‘\ II... On“
nll.0N
.ll.0m
0..
/ Ipl‘.\ 0.¢ mm J 04
mSMH 0
fine: > ooe 3:” o J om
SE a 00H mmeH 0

+++

 

 

 

Airsuequl eoueoselontg

34

.30 omlom EH

 

 

 

 

«HHHV EDHQHmu SDHB GHHOE Ho memEOU mnu Ho muuummm mocmommnosam .mH mHDmHh
.12 SH numcmHm>m3
00m 0¢m 0mm 00m 00¢ 00¢ 0¢¢ 0N¢
. _ H _ _ ac.
I I I|.0.m
- J93
0 .d
o.m mm Jo.mHm.
o
o O mom H 0 M
:HH02 2 00¢ o o 09H 0 [0.0Nm
bav u
+++QB P 00H H 0 m
I o
c I
l. C ( IOoOHw
o H.
_ A
l ll.0.0N
/. ozv mm J. .
)l.\ mmflH 0
:HHo2 a 00¢ ome 0 ll50.0¢
*
+++nH e 03 S H .

 

 

35

.30 omlom :H
AHHHV EDHHUU nuHB CHHOE mo XmHmEoo wnu Ho muuommm mocmommuosHm .¢H,mHDmHm

.12 SH Sumcme>m3

 

 

 

 

omm 0¢m 0mm 00m 00¢ 00¢ 0¢¢ 0 ¢
// J O.@
Ill 0.0H
0.m mm J 0.3 m
MQGH 0 m
- . e
:HHO2 P 00¢ om¢H 0 III 0 0m x
P mH¢ a
+++mo 00H H o w
- \ 0 a
c 1 \\\\\\\\ H
‘ ‘ D
.. ¢ .. J. 0.0H m
S
n.
, III o.om.A
/ a
D
/ 0.¢ mm IL, .
p o 0 CM
[0 mOMH 0
:HH02 0 00¢ ome 0 III 0.0¢
Maw
+++m.o 0 OOH H o

 

 

 

36

.30 omlom SH SHHOE Ho muuommm SUSmommHosHm .mH musmHm

.12 SH SumSmHm>mz

 

 

 

 

000 0¢m 000 000 00¢ 000 0¢¢ owe

_ _ _ H _ _ JvJ J40
[OJ lm.oN
J00

0.0 mm IJ.m..H
mmmH 0
mm¢H o II!0.0¢_
SHHo2 a 00¢ moeH 0

 

 

 

 

.IIIIAYII JIATI. 1 c J\\\\\\\, Jmao

O/ L0.m

a
11.0.3
I
. 0
o. \\\\!\\\\ 0 ¢ m Il-0.mH
0’ . m00H o
84H 0 J98

SHHo2 0 00¢ movH 0

 

 

 

Aqrsusqul eoueosexonTa

37

Effect of pH on Absorbance

Figures 5-7 Show the effect that a change in pH has
upon the absorbance of the complex. The absorption maximum
of the complex shifts to longer wavelengths with increasing
pH. A pH level of 5.0 was selected as the optimum pH for

studying the lanthanide (III)-morin complexes as a group.
Nature of the Complex

Isoabsorptive Point

 

Figures 16-21 Show SpectrOphotometric isoabsorptive
,pointS for the six lanthanide (III) complexes at pH 5.0.
The formation of only one isoabsorptive point suggests the
occurrence of a Single reaction (102) between the lanthanide

(III) ion and morin.
Method of Continuous Variations

The empirical formula of the complex was determined
In? employing Job's method of continuous variations. The
total molar concentration of lanthanide (III) ion and morin
was maintained constant for a series of solutions, while the
individual concentrations of lanthanide (III) ion and morin
were varied. The mole fraction of lanthanide (III) ion was
plotted against Y, the corrected absorbance which is due

only to the complex.

38

 

 

1.0
400 7 morin in 50-50 DW at pH 5.0
0.90__ 7 Cu:Ve 'Y 313+;+
1 6 2 20:0
/\ 3 40.0
0.80H— / \ I: 28.8
/ \ s 80.0
2 / 7 100.0
5 \
’ \
/ 5 \ ,/4\ \
/ z/p’ 5 \\
/ / \ J
/ \
0.50—/ / / \ \
a, V / 5/ \ \
g ,/ /'7 \
g0.“ // \ 2 \\
m _’/ \
r3: \ \\
0.30— \ \\
\ \\
\
0.20__ \ \\
\ \\
1
0.10.__ \ \\\
\ \\
\\\\
\\
0 l l l l l l $4 I l

 

 

 

320 340 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.

Figure 16. Spectrophotometric isoabsorptive point for
the complex of morin with samarium (III);

Absorbance

39

 

 

 

1.00
400 y morin in 50-50 DW at pH 5.0
7
Curve 7 Pr+++
0°90— 1 0.0
2 20.0
1 ’2‘ 5 40.0
\ 4 50.0
0.80 I \ 5 60.0
/ 6 80.0
I _, \ 7 100.0
2
0070— /\ I \
/ \ / 4 \
/ \ /\ \
5 \ / / \
0.60— / ',/ \ \
/ \ \
/ é ’ ‘ \
0.50_7 // // \\ \\
/ / 6/ \ \\
,/ / \\ \\
Q'4O’—// \2 \\
.../ \ \\
\ \
0.30-—— \ \\
\\ \\
\\
0.20~—— \ \\
1 \ \\
\ ‘\
0 10,— \\ Q
\
. \ \\
\Ԥ\
0 J J J J J J I I I J

 

 

 

320 340 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.

Figure 17. Spectrophotometric isoabsorptive point for the
complex of morin with praseodymium (III).

40

 

 

1.00
400 y morin in 50-50 DW at pH 5.0
+++
Curve 7 Nd
0'90 7 1 0.0
2 20.0
5 40.0
1 4 50.0
O'BO— /§ 5 60.0
6 80.0
/ \ 7 100.0
2“ / \
/ x \
.70
O r-' / \ / \
/ \ /
/ \
/
0.60— __ -4 \
/ / ,/ \ \
8 )l/5 3‘\
£0504 / / \ \ \
‘4 / 6’ \ \ \
° \
U) I \
.0 / \
d /' / \ \
0.40. / \ \
/ \2 ‘\
/ \ \\
0.50._ \ \
\
\ \
\ \
\\
0.20— \ \\
1 \\\\‘
0.10__ \ \\
\\
\\‘
0 J J J i J J \ --J-- J J

 

 

320 340 360 380 400 420 440 460 480 500 520 540

Figure 18.

Wavelength in Mu.

Spectrophotometric isoabsorptive point for
the complex of morin with neodymium (III).

 

41

 

1.00
400 y morin in 50-50 DW at pH 5.0
0,90... Curve 7 Tm+++
1 1 0.0
2 20.0
3 40.0
7 4 50.0
O-BOF 5 60.0
6 80.0
2 7 7 100.0
0.70_ /\
/ \
\ 6
/ 5 ,\
/ 4. ‘ /
0.604 / \\ / \
m / / \\ / \
6
2 / I ’/.'\ / 5 \
(U I / \
0 / / ‘\ \
3 / / \ 5\ \
S /' / \
0.40_/ \ \ \
/ \
\ \
\ \
\ \
0.304—— \ 2 \ \
\\ \ \
\ \
\ \ \
0.20~—— \ \ \
\ \ \
1 \ \
0.10— \ \ \
\ \\
\ \ \
J l J l | l ‘ I“ J

 

 

 

 

 

0
320 340 360 380 400 420 440 460 480 500 520 540
Wavelength Mu.

Figure 19. SpectrOphotometric isoabsorptive point for the
complex of morin with thulium (III).

Absorbance

42

 

 

 

 

1.00
400 y morin in 50-50 DW at pH 5.0
0,90r_~ Curve y Tb+++
1 0.0
1 2 20.0
3 40.0
0.80——- 4 50.0
7 5 60.0
6 80.0
7 100.0
0.70— /2\ 6
/\
\ / \
/ 3 \\ /' 5‘\
0.60}— 4,
/ / \\\ / \
— \
/ I /’ \ \
0.50—f / 6/
y , / 3 \ \
/ 7 \
/ \\
/
0.40 / \ \\
/ \ \\
/
\ \
\
\
0.50— \2 \\
'\
\ \\
0 20 ‘\ \ \
. \ \\
\ \\\
0.10... 1 \ \\
\ <\
\ \
l l l l I _ ‘\ . 1
20 340 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.
Figure 20. SpectrOphotometric isoabsorptive point for the

complex of morin with terbium (III).

 

43

 

1.0
400 7 morin in 50—50 DW at pH 5.0
0 90 Curve 7 Ce+++
° ‘—_' 1 0.0
7 2 20.0
1 5 40.0
4 50.0
0’80"' 5 60.0
.E 6 80.0
/ \ 7 100.0
0.70,__ 64 / \
/ \ \
/ \ /
5 / \
/ \ 5
/ 4/-.1/’\ ‘
/ / \ \
230-50 / / 3 \ \
g / / §/’ \ \ \
'9. / , ‘ \\
8 / / 7 \ \\
g 0.40
4 _’/’ \ \\
\ \\
\\ \\
0.50~——
\\ \\
'\ \\
0.20... \\
\ \
1 \. Q
0.10_ \ \
\. \
\\
o J J J J J J 7‘ __ J J

 

 

 

 

 

520 540 360 380 400 420 440 460 480 500 520 540
Wavelength in Mu.

Figure 21. Spectrophotometric isoabsorptive point for the
complex of morin with cerium (III).

44

Both Job (137) and Vosburgh and Cooper (138) have shown
that the value of Y at each wavelength is a maximum where the
greatest amount of complex is formed. Figures 22-27 Show the
results obtained when Y is plotted against the mole fraction
of lanthanide (III) ion. The maximum, when the absorbance
due to the complex is measured, or minimum, when the absorb-
ance due to morin is measured, value of Y appears at a ratio
of one mole of lanthanide (III) ion to two moles of morin,

. . . +
Indicating a general formula of RMg for the complex.

Slope Ratio Method

 

The composition of the complexes was also determined by
the slope ratio method of Harvey and Manning (147). Figures
28-32 show that the absorbance at the maximum wavelength for
the complex plotted against the moles of morin per liter,
curve 1, and against the moles of lanthanide (III) ion per
liter, curve 2. The slope of curve 1 represents the change
in absorbance per mole of morin, and curve 2 represents the
change in absorbance per mole of lanthanide (III) ion. The
data obtained are summarized in the Appendix (Tables A-VII-
A—XI). These data confirm that the general formula of the

. +
complex Is RM2 .
Equilibrium Ratios of the Complexes

The technique used by Milkey and Fletcher (102) in their

investigation of the thorium (IV)-morin complex was employed

Absorbance

 

45

 

Maximum for 1:2 complex

 

 

 

 

1 I l I 1 I 1 I . l
o 0.2 0.4 0.6 0.8 1.0

 

 

Mole Fraction of Sm (III)

Figure 22. Determination of composition of the samarium
(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations.

Absorbance

46

 

0.4-—

0.3 _

0.1-—

Maximum for 1:2 complex

0 413 mu
0 390 mu
0 3561m1

 

 

 

1 1 1 1 1 1 1 1

 

 

Figure

23.

0.2 0.4 0.6 0.8 1.0
Mole Fraction of Pr (III)

Determination of composition of the praseodymium
(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations.

47

 

Maximum for 1:2 complex

0.61-
O 414 mu
0'5 — O 390 mu
0 356rm1
0.4 - . ,. .
o
0.3 — . .

 

Absorbance

 

 

 

 

J l ‘1 I L 1 1 I I
O 0.2 0.4 0.6 0.8 1.0

 

Mole Fraction of Nd (III)

Figure 24. Determination of composition of the neodymium
(III)—morin complex in 50-50 DW at pH 5.0 by
method of continuous variations.

Absorbance

48

 

Maximum for 1:2 complex

0 423 mu
0 390 mu
0 356Im1

 

 

 

 

 

 

-0051—
-O.4 —
1 1.111 1 1 1 1
0 0.2 0.4 0.6 0.8 . 1.0
Mole Fraction of Tm (III)
Figure 25. Determination of the composition of the thulium

(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations.

49

 

 

 

 

 

 

 

0 6 Maximum for 1:2 complex
- r
O 417 mu
0.5 — 0 390 mu
0 356Im1
0
0
S
m
Q
51.1
o
m
.0
<1
-005 '-
—004 L
1 1 1 . 1 1 1 1 1 1
0 0:? 0.4 0.6 0.8 1.0

Mole Fraction of Tb (III)

Figure 26. Determination of the composition of the terbium
(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations.

Absorbance

50

 

 

 

 

 

 

 

Maximum for 1:2 complex
0.6"
J 0 413 mu
0.5-— 0 390 mu
0 356 mp.
0.4'- . ,. .
o
0.3-— . a
o
0.2-
. o
0.1J-
0
_001 '- ‘1 .
"002 — C
-0.3 -
-0.4 —
l l » l l J l I l
0 0.2 0.4 0.6 0.8 1.0
Mole Fraction of Ce (III)
Figure 27. Determination of the composition of the cerium

(III)-morin complex in 50-50 DW at pH 5.0 by
method of continuous variations.

Absorbance 415

51

Moles Sm+++ per liter x 106 (curve 2)

10 20 30 40 50

1‘3 1 1 I

 

1.11H—-

1.0‘F—'

 

0.4 -—-

     

1. Excess Sm+++ 5.32 x 10'3M

0-2 -- 2. Excess morin 1.32 X 10'4M

 

 

 

0 . J

.10 20 50 40 50

 

Moles morin per liter x 106 (curve 1)

Figure 28. Determination of composition of the samarium (III)-
morin complex in 50-50 DW at pH 5.0 by slope-ratio
method.

Absorbance 413

52

Moles Pr+++ per liter x 106 (curve 2)

 

 

 

    

 

 

 

10 20 30 40 50
1'5 I I I 1
102 T—
1.1 ———
1.0 ——-
0.9 ——-
0.8 -——
0.7‘——-
0.6 L——
0.5 -—-
0'4 _— +++
1. Excess Pr 5.68 x 10-3M
0.5,___ 2. Excess morin 1.32 x 10-4M
0.21——
0.1 ___
0 J - V J
10 20 50 40 50
Moles morin per liter x 106 (curve 1)
Figure 29. Determination of composition of the praseodymium (III)-

morin complex in 50-50 DW at 5.0 by lepe—ratio method.

Absorbance 414

53

Moles Nd+++ per liter x 106 (curve 2)

10 20 50 40 50

 

 

    

 

1. Excess Nd+++ 5.55 x 10‘3M

2. Excess morin 1.32 x 10'4M

 

J

10 20 50 40 50

 

 

Moles morin per liter x 106 (curve 1)

Figure 30. Determination of composition of the neodymium
(III)-morin complex in 50-50 DW at pH 5.0 by

SIOpe—ratio method.

Absorbance 423

+++
Moles Tm

54

per liter x 106 (curve 2)

 

 

 

 

 

 

  

 

 

 

 

1.5 10 20 5? 4f 50
1.21——-
1.1
C)
1.0 2 1
0.9
0.8
0.7 _——
0.6 __—
0.5 ——-
0.4 ~—-
0.3 "——
1. Excess Tm+++ 4.74 x 10‘3M
0,2 ——— 2. Excess morin 1.32 x 10-4M
0.1 -——
C)
O V J
10 20 30 40 50
Moles morin per liter x 106 (curve 1)
Figure 31. Determination of composition of the thulium (III)-

morin complex in 50-50 DW at pH 5.0 by slope-ratio

method.

Absorbance 417

55

+++ . +++ .
Moles Tb per liter Moles Ce per liter

x 106 (curve 2) x 106 (curve 2)

10 20 10 20

 

0.3 *-

  

  

2. Excess morin 2. Excess morin

 

 

 

 

0'2 — 1.52 x 10‘411 — 1.52 x 10-4 M
0,1 L_. ___
O 1 , -
1O 20 10 20
.Moles Tb+++ per liter Moles Ce+++ per liter
x 106 (curve 2) x 106 (curve 2)

Figure 32. Variation in absorption of terbium (III) and
cerium (III)—morin complexes with variation in
lanthanide (III) ion concentration in presence
of large excess of morin.

Absorbance 413

56

to estimate the equilibrium ratio of the various lanthanide
(III) ion-morin complexes. The following information was
obtained to calculate the equilibrium ratios of the complexes

under the conditions of the investigation.

Absorptivity of Morin. Solutions containing morin in
the concentration range of approximately 1.0 x 10‘5 M. to
5.4 x 10'5 M., and no lanthanide (III) ions were prepared.
The solutions were adjusted to pH 5.0 and the absorbances
measured. The molar absorptivity was calculated from the
absorbance, concentration and cell width. The molar absorp-
tivity of morin at pH 5.0 and 415 mu. is 2.27 x 103 L/mole

cm., and at pH 5.0 and 423 mu. is 1.85 x 103 L/mole cm.

Absorptivity of the Lanthanide (III)-Morin Complex.
The molar absorptivities of the praseodymium, neodymium,
samarium and thulium complexes were calculated from the slope
ratio data obtained in the presence of a large excess of
lanthanide (III) ion. The large excess of lanthanide (III)
ion insured the complete reaction of all of the morin added
to form the complex. By running a blank containing excess
lanthanide (III) ion, the contribution of the colored
lanthanide (III) ion to the absorbance was determined and
subtracted from the total absorbance. Assuming that for each
two moles of morin added, one mole of complex is formed, the
molar absorptivity of the complex is equal to the absorbance
due to the complex divided by one-half of the morin concen-

tration.

57

The molar absorptivities of the cerium and terbium
complexes were calculated from absorbances measured for solu-
tions containing varying amounts of the lanthanide (III) ion
in the presence of a large excess of morin. The excess of morin
insured complete reaction to the lanthanide (III) ion to form
the complex. The observed absorbances are due both to morin
and the complex. Assuming that for each mole of lanthanide
(III) ion added, one mole of complex is formed, the uncom-
plexed morin concentration was calculated and the measured
absorbance was corrected for the morin absorbance contribu-
tion. The molar absorptivity of each complex was calculated

from the corrected absorbances.

Concentration of the Componentsjn.Solution After Complex

Formation. The calculation, as employed by Milkey and

 

Fletcher (102) to determine the concentration of the compon-
ents in a solution of the complex, was performed using the
data obtained in the continuous variations investigation.

In the lanthanide (III)-morin system at the concentra-
tion level used in the continuous variations investigation
only morin and the complex absorb radiation.

If: X = moles of complex per liter

(MH) = total moles of morin added per liter
+++
(R ) = total moles of lanthanide (III) ion per
liter
Y = moles of uncombined morin per liter

Z = moles of uncombined lanthanide (III) ion per
liter

58

A = absorbance at the desired wavelength of solu-
tions containing the complex

b = path length in cm. (1 cm.)

aMH = molar absorptivity of morin at the desired

pH and wavelength

aRM + = molar absorptivity of the complex at the
2 desired pH and wavelength

then

A aMH[(MH) - 2(X)] + aRM2+ (X)

Solving for X

A - aMH (MH)

x = aRM2+ " 2 (aMH)

The concentrations of uncombined morin and lanthanide (III)

ion remaining in solution are calculated as follows:

(MH) — 2(X)
+++

Y

(R ) - x

and Z

Calculation of the Equilibrium Ratio. Once the concen-
trations of components present in solution have been calcu-

lated, the equilibrium ratio, K'eq’ for the reaction,

+++

+
R + 2 MH = RMg + 2 H+

can be evaluated by substitution of the appropriate values

into the expression

(RM2+) (H+)2

K' —
eq <8+++1 (MH)2

where

59

+
RMa = X as calculated above
+++
(R ) = Z as calculated above
(MH) = Y as calculated above
+

(H)

the hydrogen ion concentration calculated
from the pH of the solution

The data for the calculation of the equilibrium ratios are
tabulated in the Appendix (Tables A-I - A-VI). The average
values for K'eq are 0.83, 4.3, 2.7, 7.9, 0.73 and 2.3 for
cerium, neodymium, praseodymium, samarium, terbium and
thulium, respectively. The K'eq values are averages over
the following approximate ranges of moles of lanthanide (III)
ion to morin: for cerium, 1:1 to 1:2.3; for neodymium, 1:1
to 1:4; for praseodymium, 1:1 to 1:9: for samarium, 1:1.5 to
1:2.3: for terbium, 1:0.67 to 1:4 and for thulium, 1:0.1 to
1:9. The values for cerium, neodymium, praseodymium, and
samarium are consistent with the values obtained by Fleck
(99) for lanthanum, by Weiler (100) for gadolinium and
lutetium, and by Van Eenanaam (101) for dySprosium, erbium,
europium, holmium and ytterbium. The values for terbium

and thulium are anomalous to a uniform trend in the lanthanide

(III) series of complexes.

60

 

 

 

00H 0.66 000086 0H1606 666 000 66.0 00
000 6.06 8063 001606 600 000 0.6 00
00086 8066000 6.0 8063 0Hu606 666 606 0.6 SH
000 6.00 8063 001606 600 0H0 0.6 0m
000 0.00 8063 00-606 600 000 0.6 00
000 6.00 8063 H06> 001606 606 600 0.6 00
00086 8006600 60.0 8003 001606 006 800 0.6 SH
000 6.80 000086 0H1606 666 000 66.0 00
000 1-1 8063 H00> 001606 600 0.6
000 0.60 1-1 111 -11 600 6.6 00
00086 8006000 0.0 x003 0H1606 6H¢ 6H0 0.6 06
00086 8066000 6.0 8003 001606 000 000 0.6 02
00086 8006600 8.0 8063 006-606 600 680 0.6 00
H0086 8006600 66.0 8063 001606 600 600 0.6 60
00 6.0 000086 001606 666 000 6.6 00
moSmHmmmm 00.2 >8HmS08SH .HOSHHA .uHowa .meA mm S0H
moSwomwuosHm moSmQHOmQ¢
mGOHUSHOm HOUMSIOCMXOHQ Omlom 0H
mmmeQEoo SH0021AHHHV mflHSmnuqu 000 mmeHWQOHm Hmupommm USm.mmsHm> 00.2 .H 0HQMB

SUMMARY AND CONCLUSIONS

61

62

A Spectrophotometric and spectrofluorometric investi-
gation of the complexes of morin with cerium (III),
neodymium (III), praseodymium (III), samarium (III),
terbium (III) and thulium (III) in 50-50 DW solution was
completed.

The absorption band peak of morin occurs at 356 mu.,
while the complex absorption band peaks for cerium and
praseodymium, neodymium, samarium, terbium, and thulium
occur at 413, 414, 415, 417, and 423 mu., respectively.

The complexes fluoresce only slightly more than morin
when exposed to incident radiation of 365, 436 mu. or there
absorption maximum wavelength. The complexes of lanthanum,
gadolinium and lutetium fluoresce Significantly under the
same conditions.

The pH of the solution affects the absorbance of the
complexes. A pH level of 5.0 was selected as the optimum
pH for investigating this series of complexes. The absorp-
tion maxima shift slightly to longer wavelengths with
increasing pH.

In the absorption Spectra of each of the complexes, a
single isoabsorptive point exists. The isoabsorptive point
occurs near 377 mu. The existence of an isoabsorptive point
suggests that a single complex is formed.

Job's method of continuous variations (137) and Harvey
and Manning's slope ratio method (147) were employed to

determine the empirical formula of the complex. These

63

studies indicate that a 1:2 complex, lanthanide (III):morin,
is formed.

An equilibrium ratio, K'eq’ for each of the complexes
was calculated in the manner proposed by Milkey and Fletcher
(102). The K'eq values for the cerium, neodymium, praseo-
dymium, samarium, terbium and thulium complexes with morin
in 50-50 0w at 2500 are 0.85, 4.5, 2.7, 7.9, 0.75 and 2.5,
reSpectively.

The absorbances for the complexes change linearly with
changing lanthanide (III) concentration over the approximate
concentration range, 0 to 2.3 x 10'5 M., in the presence of
excess morin, 1.32 x 10‘4 m.

The formation constants for lanthanide (III)-EDTA
(151) complexes increase regularly from lanthanum to lutetium.
In the present study, the concentration quotients for the
terbium and thulium-morin complexes are anomalous. No ex—
planation for this departure can be offered at the present
time but the reaction between these two lanthanide ions and
morin should be reinvestigated in greater detail.

Furthermore, the acid dissociation constant for morin
Should be evaluated so that the formation constant for the

reaction

R+++ + 2 M- ——\ RM2+
V.

can be calculated.

LITERATURE CITED

64

8.

9.

10.

11.

12.
13.

14.

15.

16.

17.

18.

19.

65
Fitch, F. T., and Russell, D. 5., Anal. Chem., 23, 1469
(1951).
Clinch, J. and Simpson, E. A., Analyst, 82, 258 (1957).

Willard, H. H., and Gordon, L., Anal. Chem., 29, 165
(1948).

Hagiwara, Z., Technol. Rept. Tohoku Univ., 29, 77 (1955).

. Bril, K. Y., Holzek, S., and Rethy, B., Anal. Chem., 31,

1555 (1959).
Cheng, K. L., Chemist-Analyst, 41, 93 (1958).

Crouch, E. A. C., and Swainbank, I. G., United Kingdom
Atomic Energy Authority, Rept. AERE-C/R-2843 (Feb., 1959).

Flaschka, H., Mikrochim. Acta., 1955, 55.

Fritz, J. S., Abbink, J. E., and Payne, M. A., Anal. Chem.,
§§, 1381 (1961).

Gimesi, 0., Rady, G., and Erdey, L., Periodica Polytech.,
.6. No. 1, 15 (1962): c. A., §§, 6167b (1963).

Katsumata, S., Bunseki Kagaku, 1Q, 1259 (1961); C. A.,
.58. 6173b (1963).

Lyle, S. J., and Rahman, M. M., Talanta, 1Q, 1177 (1963).
Lyle, S. J., and Rahman, M. M., Talanta, 19, 1183 (1963).

Sin, Peng—Joung, J. Chinese Chem. Soc. (Taiwan), Ser.
119, 41, (1962); c. A., 58, 2838e (1963).

Tereshin, G. S., and Tananaev, I. V., Zh. Analit° Khim.,
11, 526 (1962); c. A., 61, 144208 (1962).

Kugai, L. N., and Nazarchuk, T. N., Zh. Analit. Khim., 16,
205 (1961); c. A., §§, 122999 (1962).

Pershkova, V. M., Gromova, M. I., and Aleksandrova, N. N.,
Zh. Analit. Khim., 11, 218 (1962); N. s. A., 16, 18842
(1962).

Pershkova, v. M., Gromova, M. I., Efimov, I. P., and
Isachenko, A. V., Vestnik. Moskov. Univ. Khim., Ser. II
16, No. 4, 59 (1961); c. A., 56, 7980a (1962).

Kugai, L. N., Tr. Seminara po Zharostoikim Materialam,
Akad. Nauk Urr. SSR., Inst. Mettalokeram. i Spets. Splavov,
Kiev, 1960; C. A., 12300b (1962).

20.

21.

22.

23.

24.

25.

26.

27.

28.

29.

30.

31.

32.

33.

54.

35.

66

Kuteninikov, A. F., and Brodskaya, V. M., (All-Union
Scientific Institute of Mineral Resources, USSR),
Zavodskaya Lab., 29, 792 (1962); N. S. A., 19, 26940
(1962).

Onosova, S. P., Zavodsk. Lab., 29, 271 (1962); C. A.,
51. 2836f (1962).

Tikhonov, V. N., Tr. Vses. Nauchn.-Issled. Alyumin.-
Magnievyi Inst., 1961, No. 47, 145; C. A., 91, 40101
(1962). "”"

Moret, R., and Brunesholz, G., Chimia (Switz.), 19, 313
(1961): C. A., 99, 11354d (1963).

Bruecher, E., and Szarvas, P., Acta. Chim. Acad. Sci.
Hung., 92, 31 (1967): C. A., 91, 57728f (1967).

Plaksin, I. N., Strizhko, V. S., and Fedotov, Y. S.,
Dokl. Nauk SSSR, 174, 162 (1967); C. A., 91, 6814k (1967).

Powell, J. B., and Berkholder, H. R., J. Chromatogr.,
29, 210 (1967): C. A., él, 96476s (1967).

Sakodynskii, K. I., Zh. Neorg.thim., 12, 2171 (1967):
C. A., El, 104796p (1967).

Spedding, F. H., and Daane, A. H., editors, "The Rare
Earths," John Wiley and Sons, New York, 1961.

Trifonov, D. N., "The Rare Earth Elements," Prasenjit
Basu translator, R. C. Vickery editor, Macmillan,
New York, 1963.

Vickery, R. C., "Analytical Chemistry of the Rare Earths,"
Pergamon Press, New York, 1961.

Pollard, F. H., McOmie, J. F. W., and Stevens, H. M.,
J. Chem. Soc., 3436 (1954).

Banks, C. V., and Klingman, D. W., Anal. Chim. Acta.,
ifi. 356 (1956).

Moeller, T., and Brantley, J. C., Anal. Chem., 22, 433
(1950).

Onstott, E. I., and Brown, C. J., Anal. Chem., 99, 172
(1958).

Palmino, J. V., Castillo, F., and Cellini, R. F., Anales.
Real Soc. Espan. Fiz. Quim. (Madrid), Ser. B, 99, 303
(1965); c. A.,,ég. 10758g (1965).

36.

37.

38.

39.

40.

41.

42.

43.

44.

45.

46.

47.

48.

49.

50.

51.

52.

53.

54.

67
Schultz, C. G., U. S. Atomic Energy Comm. TID-6423,
6 pp., 1957, (declassified 1959).
Stewart, D. c., AEC, Rept. AECD-2389 (Sept., 1948).
Stewart, D. C., AEC, Rept. ANLr5624 (Oct., 1956).
Ganopol'skii, V. I., Ganopol'skaya, T. A., and Barkovskii,
v. F., Zh. Analit. Khim., 19, 729 (1963); c. A., §9,
8116c (1963).

Holleck, L., and Hartinger, L., Angew. Chem., 91, 648
(1955).

Scherbov, D. P., Mirkin, V. A., and Klimov, V. V., Tr.
Kazarkhsk. Nauchn-Issled. Inst. Mineral'n Syr'ra,

1960, No. 5, 296; c. A., 91, 9194h (1962).

Stewart, D. C., and Kato, D., Anal. Chem., 99, 164 (1958).
White, J. C., and Apple, R. F., Talanta, 2, 176 (1959).

Moeller, T., and Brantley, J. C., J. Am. Chem. Soc., 12,
5477-(1950).

Rodden, C. J., J. Research Natl. Bur. Standards, 29,
265 (1941).

Prajsnak, D., Chem. Anal. (Warsaw), 9, 71 (1963); C. A.,
56, 13114c (1965).

Sheka, Z. A., and Sinyavskaya, E. I., Zh. Analit. Khim.,
2§J 460 (1963); C. A...§2. 2157g (1963).

Tonosake, K., and Otono, M., Bull. Chem. Soc. Japan,
.99, 1683 (1962); C. A., 99, 1902e (1962).

Takahashi, K., Buneski Kagaku, 19, 343 (1964); C. A.,
61, 1263b (1964).

Munshi, K., and Dey, A., Chemist-Analyst,.9§, 105 (1964).

Babko, A. K., Ukr. Khim. Zh., 92, 879 (1966);
c. A., 66, 16182j (1967).

Sheka, Z. A., and Sinyavskaya, E., Zh. Neorg. Khim.,
12, 650 (1967); C. A., 61, 477632 (1967).

Fomenko, L. D., Okun, A. E., and Yampol'skii, M. Z., Uch.
Zap. Kursk. Gos. Pedagog Inst., 29, 216 (1966); C. A.,
fil, 104847f (1967).

De Wet, W. J., and Behrens, G. B., Anal. Chem., 19, 200
(1968).

55.

56.

57.

58.

59.

60.

61.

62.

63.

64.

65.

66.

67.

68.

69.

70.

71.

68

Rinehart, R. W., Anal. Chem., 29, 1820 (1954).

Illner, E., 2. Chem., 1, 51 (1967); c. A., gg, 120366h
(1967).

Sangal, s. P., J. Prakt. Chem., §§, 126 (1967); c. A.,
61, 10482a (1967).

Sangal, S. P., Microchem. J.,._2, 321 (1967); C. A., 91,
113419V (1967).

Admad, J., Ahmad, N., and Rahman, S. M. F., J. Ind.
Chem. Soc., 11, 444 (1967); c. A., 99,7847u (1968).

Holleck, L., Eckhardt, D., and Hartinger, L., Z. Anal.
Chem., 146, 103 (1955).

Kononenko, L. I., Mishchenko, S. A., and Poluektov,
N. s., Zh. Analit. Khim., 21, 1592 (1966); c. A., 99,
51953h (1967).

Poluektov, N. S., Vitkun, R. A., Tishchenko, M. A., and
Kononenko, L. I., Zh. Prikl.~Spektrosk., 9, 625 (1966);
c. A., §§, 89928s (1967).

Dagnall, R. M., Smith, R., and West, T. 8., Analyst
(London), 92, 358 (1967).

Sangal, S., and Dey, A., Microchem. J., _2, 168 (1967);
c. A., g1, 47728t (1967).

Sinha, S. N., Sangal, S. P., and Dey, A. K., Chemist-
Analyst, 99, 59 (1967).

Moeller, T., and Telotsky, M., J. Am. Chem. Soc.,_ll,
2649 (1955).

Sarma, T. P., and Rao, B., J. Sci. Ind. Research (India),
14B, 450 (1964).

Sinha, S. N., Sangal, S. P., and Dey, A. K., J. Ind.
Chem. Soc., 11, 203 (1967); C. A., 91, 28868w (1967).

Ishida, R., and Hasegawa, N., Bull. Chem. Soc. Jap.,
19, 1153 (1967); C. A., 91, 104879t (1967).

Spacu, S. P., and Polostinaru, 8., Rev. Roum. Chim.,
12, 388 (1967); C. A., 61, 35438e (1968).

Takano, T., Bunseki Kagaku, 19, 1087 (1966); C. A.,
61, 7708d (1967).

69

72. Mal'kova, T. V., Fateeva, N. A., and Yatsimirskii, K. B.,
Zh. Neorg. Khim.. ng 915 (1967); C. A., §1J 26380g (1967).

73. Akhmedli, M. K., and Gambarov, D. G., Zh. Analit. Khim.,
22, 1183 (1967); C. A., 99, 18399a (1968).

74. Prafsnar, D., Chem. Anal. (Warsaw), 11, 1111 (1966);
c. A., 61, 77289 (1967).

75. Takano, T., Bunseki Kagaku, 19, 27 (1967); C. A., 91,
3984w (1967).

76. Shimizu, T., Bunseki Kagaku, 19, 233 (1967); C. A.,
.91. 87476q (1967).

77. Negoiu, E., An. Univ. Bucharesti, Ser. Stiint. Natur.,
$2, 57 (1965); C. A., él. 78703j (1967).

78. Shigematsu, T., and Uesugi, K., Bunseki Kagaku, 19, 467
(1967); c. A., 61. 113452a (1967).

79. Budeninsky, B., Collection Czech. Chem. Commun., 29,
2902 (1963); C. A...§Q. 3478d (1964).

80. Fritz, J. S., Abbink, J. E., and Payne, M. A., Anal.
Chem., 99, 1381 (1961).

81. Hiiro, K., Russell, 8., and Berman, S. 8., Anal. Chim.
Acta., 91, 209 (1967); c. A., 99, 82104m (1967).

82. Akmaeva, N. L., Dedkov, Y. M., and Khramov, V. P.,
Zh. Anal. Khim., 22, 1482 (1967); C. A., 99, 56214u (1968).

83. Munshi, K., and Dey, A. K., Anal. Chem., 99, 2003 (1964).

84. Akhmedli, M. K., and Gramovskaya, P. B., Izv. Vyssh.
Ucheb. Zaved., Khim. Khim. Technol., 19, 271 (1967);
c. A., 91, 113445a (1967).

85. Budeninsky, B., and Vrzalova, D., Anal. Chim. Acta., 99,
248 (1966).

86. Kirillov, A. I., Lauer, R. S., and Poluektov, N. S., Zh.
Analit Khim., 22, 1333 (1967); C. A., 99, 26683d (1968).

87. Pribil, R., and Vesely, V., Chemist-Analyst, 91, 100
(1965).

88. Plaskin, I. N., Strikzhko, V. S., and Fedotov, Y. S.,
Dokl. Acad. Nauk SSSR, 174, 162 (1967); C. A., 91, 68141k
(1967).

89.

90.
91.

92.

93.

94.

95.

96.

97.

98.

99.

100.

101.

102.

103.

104.

105.

106.

70
Milner, O. I., and Gedansky, S. J., Anal. Chem., 91,
931 (1965).
Pribil, R., Talanta, 19, 1711 (1966).
Pribil, R., Talanta, 11, 313 (1967).

Pribil, R., and Vesely, V., Chemist-Analyst, 99, 23
(1967).

Galaktinov, Yu P., and Astakhov, K. V., Zh. Neorg. Khim.,
11, 2269 (1966); C. A., 91, 6220b (1967).

Kovar, L., and Powell, J., U. S. At. Energy Comm. IS-1450,
54 pp., N. s. A., 29, 45623 (1966).

Krishnamurthy, V. N., and Soundarajan, S., J. Less-Common
Metals, 19, 263 (1967); C. A., 91, 78569v (1967).

Adachi, G., Shiokawa, J., and Ishino, T., Kogyo Kagaku
Zasshi, 19, 431 (1967); C. A., 91, 70155m (1967).

Megal, P. K., and Chebotar, N. G., Zh. Neorg. Khim., 12,
1190; C. A.,.él, 76717t (1967).

Kabachnek, M. I., Dyatlova, M., Medved, T. Y., Belugin,
Y. F., and Sidorenko, V. V., Dokl. Acad. Nauk SSSR, 175,
351 (1967); C. A., El, 120502v (1967).

Fleck, L. L., Ph. D. Thesis, Michigan State University,
East Lansing, Michigan.

Weiler, J. E., M. S. Thesis, Michigan State University,
East Lansing, Michigan.

Van Eenenaam, R. H., M. S. Thesis, Michigan State Univer-
sity, East Lansing, Michigan.

Milkey, R. G., and Fletcher, M. H., Anal. Chem., 29,
1403 (1956).

Katyal, M., Talanta, 19, 95 (1968).

Pringsheim, P., "Fluorescence and PhOSphorescence,"
Interscience, New York, 1949.

Bowen, E. J., and Wokes, F., "Fluorescence of Solutions,"
Longmans, Green and Co., New York, 1953.

Hercules, D. M., editor, "Fluorescence and PhOSphorescence
Analysis," Interscience, New YOrk, 1966.

107.
108.
109.

110.

111.

112.

113.

114.

115.

116.

117.

118.

119.

120.

121.

122.

123.

71

White, c. E., Anal. Chem., 99, 116R (1964).
White, c. E., Anal. Chem., 99, 155R (1966).

Poluektov, N. S., and Kononenko, L. I., Sovrem. Metody
Analiza, Metody Issled. Khim. Sostava i Shroeniya
Veschchestv, Akad. Nauk SSSR, Inst. Geokhim. i Analit.
Khim., 1965, 96; C. A., R2721d (1966).

Kononenko, L. I., Lauer, R. S., and Poluektov, N. S.,
J. Anal. Chem. USSR, 19, 1279, Eng. Tr. (1963).

Stanley, E. C., Kinneberg, B. I., and Varga, L. P.,
Anal. Chem., 99, 1562 (1966).

Melby, L. R., Rose, N. J., Abramson, E., and Caris,
J. C., J. Am. Chem. Soc., 99, 5117 (1964).

Efryushina, N. P., and Poluektov, N. S., Zh. Analit.
Khim., 29, 1073 (1965); C. A., 91, 5747e (1966).

Yuan, K., Yao, K., Hu, C., and Chen, S. Hua Hsueh
Hsueh Pao, 92, 169 (1966); C. A., 99; 13194b (1966).

Onishi, H., and Toita, Y., Anal. Chem., 99, 1867 (1964).

Lebedev, O. L., Magdesieva, N. N., Michurina, A. V.,
Ainitdinov, K. A., and YUr'ev, Y. K., Zh. Strukt. Khim.,
.1: 521 (1966): C. A., 99, 6842q (1967).

Melent'eva, E. V., Kononenko, L. I., Koltunova, E. G.,
and Poluektov, N. S., Zh. Prikl. Spektrosk., 9, 328
(1966); C. A., fig, 60503 (1967).

Derkacheva, L., Kudryavtseva, A. D., Peregudov, G. V.,
and Sokolovskaya, A. I., Zh. Prikl. Spektrosk, 9, 346
(1967); c. A., .61. 48795y (1967) .

Butter, E., Seifert, W., and Holzapfel, H., Z. Chem.,

1, 25 (1967); c. A., 61. 48803z (1967).

Crosby, G. A., Whan, R. E., and Alire, R. M., J. Chem.
Phys., 54, 743 (1961).

Whan, R. E., and Crosby, G. A., J. Mol. Spectry., 9,
315 (1962).

Kononenko, L. I., Lauer, R. S., and Poluektov, N. S.,
J. Anal. Chem. USSR, 19, 1279 Eng. Tr. (1963).

Kononenko, L. I., Poluektov, N. S., and Nikonova, M. P.,
Zavod. Lab., 99, 799 (1964).

124.

.125.

126.

127.

128.

129.

130.

131.

132.

133.

134.

135.

136.

137.

138.

139.

140.

72

Kononenko, L. I., Tishchenko, M. A., and Poluektov, N. S.,
J. Anal. Chem. USSR. 12, 770 Eng. Tr. (1964).

Lyons, H., and Bhaumik, IAA Accession No. A64-23435.

Lempicki, A., Samuelson, H., and Brecher, C., Appl. Opt.
Suppl., No. 2, 205 (1965).

Brecher, C., Samuelson, H., Lempicki, A., and BrOphy,
V. A., NASA Accession No. N65-15508, Rept. No. AD 447468,
19 pp. (1964); C. A., 99, 17356h (1965).

Samuelson, H., Brecher, C., and Lempicki, A., J. Chim.
Phys., 91, 165 (1967); C. A., 91, 489338 (1967).

.Ross, D., and Blanc, J., Advan. Chem. Ser., No. 11, 155

(1967); c. A., 69, 34583m (1968).

Alberti, G., Massucci, M. A., and Saini, A., Atti. Accad.
Nazl. Lincei, Rend., Classe Sci. Fiz., Mat. Nat., 91,
173 (1963); C. A., 99, 12654h (1964).

Akhmedli, M. K., and Bashirov, A. A., Uch. Zap. Azerb.
Gos. Univ., Ser. Khim. Nauk, 1963, 39; C. A., 92, 189
(1964).

Akhmedli, M. K. and Glushchenko, E. L., Zh. Analit.

,Khim., 19, 556 (1964); c. A.,91, 4934f (1964).

Dombi, J., Ketskemety, I., and Kozma, L., Optika i
Spectroskopiya, 19, 710 (1965); C. A., 99, 51289 (1965).

Kozma, L., Acta. Univ. Szeged., Acta. Phys.-Chem., 9,
59 (1963); C. A., 99, 11566b (1966).

Fletcher, M. H., Anal. Chem., 91, 550 (1965).

.Nowicka-Jankowska, T., Szysko, H., and Minczewski, J.

Acta. Chim. Acad. Sci. Hung., 95, 155 (1962); c. A.,
6g, 2128b (1968).

Job, P., Ann. Chim. (Paris), 9 (10), 113 (1928).

Vosburg, W. C., and Cooper, G. R., J. Am. Chem. Soc.,
§§J 437 (1941).

Katzin, L. I., and Gebert, E., J. Am. Chem. Soc., 12,
5455 (1950).

Bent, H. E., and French, C. L., J. Am. Chem. Soc.,
.99, 568 (1941).

141.

142.
143.

144.

145.

146.

147.

148.

149.

150.

151.

73

Yoe, J. H., and Jones, A. L., Ind. Eng. Chem. Soc.,
Anal. Ed., 19, 111 (1944).

Hagenmuller, P., Ann. Chim. (Paris), 9 (12), 5 (1951).

Hagenmuller, P., Compt. Rend., 230, 2190 (1950).

Betts, R. H., and Michels, R. K., J. Chem. Soc., 1949,
S286.

Shaeppi, Y., and Treadwell, W. D., Helv. Chim. Acta.,
g. 577 (1948).

Schwarzenbach, G., Helv. Chim. Acta., 92, 839 (1949).

Harvey, A. E., Jr., and Manning, D. L., J. Am. Chem.
Soc., 12, 4488 (1950).

Hess, K., and Frahm, H., Ber., 11, 2627 (1938).

Fieser, L. F., "Experiments in Organic Chemistry,"
3rd Ed., Heath & Co., Boston, 1955, pp. 284-5.

Schwarzenbach, G., "Complexometric Titrations,"
Interscience Publishers Inc., New York, 1957, pp. 55-6.

Yatsimirskii, K. B., and Vasilev, V. P., Consultants
Bureau, New York, 1960, p. 185.

APPENDIX

74

75

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