Crystal Structure Theory and Applications, 2012, 1, 97-99
http://dx.doi.org/10.4236/csta.2012.13018 Published Online December 2012 (http://www.SciRP.org/journal/csta)
Characterization, XPS and Toxicological Study of
Organothallium (III) Compounds with Schiff Base Ligands
Gyanendra Kumar Gaur1*, Shekhar Srivastava2
1Scientific Officer, Forensic Science Laboratory, Gwalior, India
2Reader in Chemistry, University of Allahabad, Allahabad, India
Received October 23, 2012; revised November 21, 2012; accepted November 29, 2012
ABSTRACT
Many Organothallium Compounds have been used in medicine, industry and antibacterial activity. Optical properties
are among the most fascinating and useful properties of many complexes and have been extensively studied using a
variety of optical spectroscopic techniques. A basic understanding of the optical properties and related spectroscopic
techniques is essential for characterization about semiconductors, insulators or metal. Optical properties are related to
other properties and functionalities (e.g. electronic, magnetic, and thermal) that are of fundamental importance to many
technological applications, such as energy conversion, chemical analysis, biomedicine, opto-electronics, communication,
and radiation detection. The fundamental importance of Thallium is the ability to accept electrons due to empty d-orbi-
tals and thus establish additional bonds (σ bond and π bond) in chemistry. The Thallium metal, which has outer elec-
tronic configuration 6 s2, 6 p1 shows oxidation states of Thallium (III) and Thallium (I). This research paper explains
that Thallium (III) and Thallium (I) accepts lone pairs from various bi-dentate tetra-dentate Schiff base ligands due to
p-orbital and vacant d-orbital. This research paper explains the Characterization, XPS and Toxicological Study of Or-
ganothallium (III) Compounds with Schiff base ligands by physiochemical technique. X-Ray photoelectron spectrogra-
phy (XPS) study of Thallium (III) complexes with Schiff Base ligands also reported in this paper. XPS study shows a
single symmetrical peak without any splitting in photoelectron peak, which confirms diamagnetic nature of all prepared
molecular adducts. All prepared complexes with Schiff base ligands show toxicological effect.
Keywords: Oxidation; Ligand; Diamagnetic; Organothallium Compound; Molecular Adducts
1. Introduction
The organometallic chemistry has developed rapidly in
III-B group of metals like gallium, indium and thallium
during few years. The organometallic compounds of these
metals have found useful applications in the production
of metal carbonyls [1], metal cyclo-pentadiencyls [2-4]
and ultra pure metals [5,6]. Some important applications
of organometallic compounds of the metals are used as
lubricants [7], antiknock reagents [8] and polymerization
catalysts for olefins [9-11]. Poisoned food technique and
Toxicological study has been recently employed to de-
termine the fungicidal activity of these compounds. Pre-
liminary evaluation of biocidal activity of some compounds
against tomato seedlings has indicated that organometa-
llic compounds of these metals are potential fungicides
[12].
2. Experimental Details
The physicochemical technique was used for synthesized
organothallium (III) in present work. The elemental
analysis was determined on a semimicro scale at Central
Drug Research Institute, Lucknow, India. Molar conduc-
tance of all complexes was measured at room tempera-
ture in Acetone by Digisun Electronics Conductivity
Bridge. The X-ray photoelectron spectra (XPS) were
recorded by VG Scientific ESCA-3MK II electron spec-
trometer at National Chemical Laboratory, Poona-6. The
MgKα X-ray line (1253.6 eV) was used for photo excita-
tion. The Cu2p3/2 (B.E. = 932.8 ± 0.2 eV) and Au4f7/2
(B.E. = 368.2 eV) was used for cross-checking. All the
spectra were recorded using the same spectrometer pa-
rameters of 50 eV pass energy and 4 mm slit width. The
reduced full width at half maximum (FWHM) at the
Au4f7/2 (B.E. = 83.8 eV) level under these conditions was
1.2 eV [13].
3. Chemical Analysis
The powdered sample was mixed with high purity silver
powder to reduce the charging effect. A thin layer of
such a sample was pressed on a gold metal gauge which
*Corresponding author.
C
opyright © 2012 SciRes. CSTA

G. K. GAUR, S. SRIVASTAVA
98
was welded to nickel sample holder. The Ag3d5/2 level
(BE = 368.2 eV) obtained which was sharp and did not
show any observable shift. Thus, the charging of the
sample was negligible. The spectra were recorded in trip-
licate in the region. In different cases the binding ener-
gies were reproducible within ±0.1 eV.
The physicochemical technique was used for prepara-
tion of hydrated Thallium (III) Chloride (TlCl3·4H2O).
Thallium Chloride (TlCl) was obtained from reacting
Thallium Methal with HCl in 1:1 molar ratio in the pre-
sence of HNO3 and H2SO4. Hydrated Thallium (III)
Chloride was obtained by passing a current of Chloride
through an aqueous suspension of Thallium (I) Chloride
till a clear solution was obtained. The solution was then
concentrated in a current of Chloride at 60˚ and cooled in
a freezing mixture and salt to yield colorless plates of
Tetra-hydrated Thallium (III) Chloride (TlCl3·4H2O).
Phenyl Thallium Chloride (PhTlCl2) has been prepared
by the reaction of Thallic Chloride with Phenylboric acid
in water. It has been recrystallised from water [14].
Phenylboric acid was obtained from phenyl magnesium
bromide and n-butylborate in ether [15]. Among the or-
ganmetallics of the III (B) group of elements, those of the
general formula RMX2 (where R = Ph, X = Cl) have re-
ceived considerable attention of the workers due to their
significantly high thermal stability.
RMX2 (where R = Phenyl, M = Tl, and X = Cl) have
sp2 hybridization with one vacant p-orbital and five
d-orbital. These vacant orbital can accept lone pair from
various donors and form molecular adducts of the type
RMX2D; RMX2L where (D = monodenate donor; L =
bidenate donor). Many PhTlCl2 complexes with bidenate
Schiff base ligands have been synthesized and charac-
terized by physicochemical technique. Table 1 shows the
analytical data of Phenyl Thallium Chloride (PhTlCl2
SB).
Table 1. Analytical data of Phenyl Thallium Chloride
(PhTlCl2·SB).
S.No. Complex % Found (calculated)
Molar
conductance in
acetone
(ohm–1cm2
mol–1)
Tl C H N
1. PhTlCl2SB13 31.6
(31.77)
44.4
(44.85)
3.4
(3.58)
8.3
(8.72) 25
2. PhTlCl2SB14 34.4
(34.45)
40.4
(40.54)
3.2
(3.34)
9.2
(9.45) 26
3. PhTlCl2SB15 33.2
(33.22)
42.6
(42.99)
3.1
(3.09)
9.0
(9.12) 28
4. PhTlCl2SB16 36.0
(36.17)
38.1
(38.29)
3.0
(3.01)
9.5
(9.92) 30
5. PhTlCl2SB17 31.4
(31.92)
45.0
(45.07)
3.0
(3.12)
8.6
(8.76) 22
4. Results and Discussion
The complex of Organothellium (III) with bidenate Schiff
base ligands and molecular adducts have been synthe-
sized and characterized by the interaction of PhTlCl2 in
Chloroform. It is clear from Table 1 that these com-
plexes were stable towards atmospheric oxygen, moisture
and at room temperature on long time. Molar conduc-
tance of 10–3 M solution of the complexes was deter-
mined at room temperature. Figure 1 shows the geomet-
rical structure of PhTlCl2 with schiff base ligands which
confirmed their stability. It is observed that the absence
of Ionic species in the range of 20 ohm–1 cm2 mol–1 to 30
ohm–1 cm2 mol–1 in acetone. All the molecular adducts
exhibit the C = N absorption around 1620 cm–1 to 1610 cm–1
which normally appears at 1640 cm–1 in the free ligands.
The lowering of this band in the complexes indicates the
coordination of nitrogen atoms of Azomethine group to
the Thallium (II) and Thallium (III). Figure 2 shows the
N1s photoelectron peak and binding energy (eV) of
PhTlCl2 with Schiff base ligands. It is observed that the
PhTlCl2·SB shows Tl4f, N1s and 01s photoelectron peak
from X-ray photoelectron spectra (XPS) study. XPS
study shows that the binding energy increases as well as
the electron density on Thallium metal ion by coordina-
tion of Schiff base ligands with Thallium metal ion.
Figure 1. The Geometrical structure of PhTlCl2 with Schiff
base ligands.
PhTlCl
2
SB
1
3
SB
13
389 395 401 407
N1s Photoelectron Peak
Figure 2. N1s photoelectron peak and binding energy (eV)
of PhTlCl2 with Schiff base ligands.

G. K. GAUR, S. SRIVASTAVA
99
5. Conclusion
It is clear that the photoelectron peaks towards higher
binding energy side due to L → M charge transfer from
XPS Study. All prepared complexes are stable under at-
mospheric conditions at room temperature and it is con-
firmed through their geometrical structure. XPS study
shows a single symmetrical peak without any splitting in
photoelectron peak, which confirms diamagnetic nature
of all prepared molecular adducts. Toxicological study of
these complexes found very prominent.
6. Acknowledgements
I am thankful to the Central Drug Research Institute,
Lucknow, India for elemental analysis of Thallium (III)
and National Chemical Laboratory, Poona-6 for X-ray
photoelectron spectra (XPS).
REFERENCES
[1] H. E. Podall and H. Shapire, “The Organmetallic Chem-
istry of the Transition Metals,” Wiley, Chichester, 1960.
[2] C. C. Hant and J. R. Doyle, “Synthesis of Cyclopentadi-
enide Derivatives,” Inorganic and Nuclear Chemistry
Letters, Vol. 2, No. 10, 1966, pp. 283-288.
doi:10.1016/0020-1650(66)80043-0
[3] A. N. Nesmeyanov, R. B. Materikova, N. S. Kochetkova
and R. V. Luk’yanova, “Preparation of Diphenylnickel
with Cyclopentadienylthallium,” Bulletin of the Academy
of Sciences of the USSR, Division of Chemical Science,
Vol. 18, No. 4, 1969, p. 896.
[4] R. B. King and M. B. Bisnette, “Initial Examples of the
Synthesis of Cp*-Metal Complexes,” Journal of Organo-
metallic Chemistry, Vol. 8, 1967, pp. 287-297.
[5] C. Seamus, X. G. Ji, I. C. Douqlas and P. Michael, “Proc-
ess for the Production of Ultra Pure Metals from Oxide
and Their Cold Rolling to Ultra Thin Foils for Use as Par-
ticle Accelerator Targets and Reference Materials,” Spe-
cial Issue of Nuclear Instruments and Methods in Physics
Research, 2000.
http://publications.jrc.ec.europa.eu/repository/handle/111
111111/11716
[6] R. Detzer, “Hochreine Metalle Durch Elektroraffination
in Metallorganischen Komplexsalzschmelzen,” Chemie
Ingenieur Technik, Vol. 36, No. 6, 1964, pp. 616-637.
doi:10.1002/cite.330360606
[7] M. Antler, “Materials, Coatings and Platings, in Electrical
Contacts: Principles and Applications,” Marcel Dekker,
New York, 1999.
[8] S. Samson and G. R. Stephenson, “Pentacarbonyliron,” In:
L. Paquette, Ed., Encyclopedia of Reagents for Organic
Synthesis, John Wiley & Sons, New York, 2004.
[9] R. Hoff and R. T. Mathers, “Handbook of Transition Me-
tal Polymerization Catalysts,” John Wiley & Sons, New
York, 2010.
[10] G. J. P. Britovsek, V. C. Gibson and D. F. Wass, “The
Search for New-Generation Olefin Polymerization Cata-
lysts: Life beyond Metallocenes,” Angewandte Chemie
International Edition, Vol. 38, No. 4, 1999, pp. 428-447.
doi:10.1002/(SICI)1521-3773(19990215)38:4<428::AID-
ANIE428>3.0.CO;2-3
[11] M. Bochmann and I. Organometallics, “Complexes with
Transition Metal-Carbon σ-Bonds,” Oxford University
Press, New York, 1994.
[12] T. N. Srivastava and K. K. Bajpai, Journal of Organome-
tallic Chemistry, Vol. 31, No. 1, 1971, pp. 1-3.
doi:10.1016/s0022-328x(00)87457-4
[13] S. Srivastava, “ESCA Studies of Metal Complexes,” Ap-
plied Spectroscopy Reviews, Vol. 22, No. 4, 1986, pp.
401-535. doi:10.1080/05704928608060441
[14] F. Challenger and B. Parker, “CXCIX—A Method for the
Preparation of Some New Organo-Thallium Halides,”
Journal of the Chemical Society, 1931, pp. 1462-1467.
doi:10.1039/jr9310001462
[15] F. R. Bean and J. R. Johnson, “Derivatives of Phenylboric
Acid, Their Preparation and Action upon Bacteria. II.
Hydroxyphenylboric Acids,” Journal of the Chemical So-
ciety, Vol. 54, No. 11, 1932, pp. 4415-4425.
doi:10.1021/ja01350a045