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Indian Journal of Chemistry
Sect. A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical
VOLUME 41A
NUMBER 2
FEBRUARY 2002
CONTENTS
Advances in Contemporary Research
245
Developments of water electrolysis technology
by solid polymer electrolyte
Sang-Do Han, Kee-Bae Park, Ravi Rana &
K C Singh*
Water electrolysis by solid polymer electrolyte is the most
promising technology for large-scale hydrogen production
for future. In this review, the selection of high activity
electrocatalysts, methods to prepare SPE electrocatalyst
composites, their stability, the pretreatment of solid
polymer electrolyte membrane for the deposition of
electrocatalysts, the fabrication of current collectors, the
scale up of water electrolyzers and recent advances has
been discussed.
Papers
254
Direct determination of the He–Kr interaction
potential
from
the
extended
principle of corresponding states
Elaheh K Goharshadi* & Majid Moinossadati
259
Para-selective ethylation of t-butylbenzene with
diethyl carbonate over mesoporous molecular
sieves
V Umamaheswari, M Palanichamy, Banumathi
Arabindoo & V Murugesan*
266
Refractive indices of binary liquid mixtures of
(decane + benzene) and (hexadecane + benzene,
or + hexane) at 303.15, 308.15 and 313.15 K
S C Bhatia*, Neelima Tripathi & G P Dubey
270
Kinetics and mechanism of permanganate
oxidation
of
phenylphosphinic
acid
in acid perchlorate solution
Kamla Sharma & Raj Narain Mehrotra*
The pair potential energy function of He–Kr determined
using a direct inversion of the experimentally reduced
viscosity collision integrals is in good agreement with the
previously determined potential. It has been used to predict
the viscosity and diffusion coefficients of He-Kr binary
mixtures.
The vapour phase ethylation of t-butylbenzene (t-BB)
with diethyl carbonate has been studied over
mesoporous molecular sieves. The selectivity of para-tbutylated products is favoured at lower temperature while
higher temperature favoures ethylbenzene.
Refractive indices of the binary liquid mixtures of (decane
+ benzene), and (hexadecane + benzene, or + hexane) have
been determined over the entire composition range.
Deviations at different temperatures have been computed
and fitted to the Redlich-Kister polynomial equation to
derive the binary coefficients.
Kinetics and mechanism of permanganate oxidation of
phenylphosphinic acid has been determined in acid
perchlorate solution The stoichiometry of the title reaction
is expressed by the equation, MnO4 + 2C6H5HP(O)OH +
4H+ Mn(III) + 2C6H5PO(OH)2 + 2H2O. The kinetics and
the rapid scan of the reaction mixture suggest the
formation of the complexes by C6H5HP(O)OH(C1, K1) and
C6H5HP(O)O (C2, K2) with MnO4 ion.
279
Synthesis,
structure,
spectroscopy
and
antitumor activity of hydroxy naphthoquinone
thiosemicarbazone and its metal complexes
against MCF-7 human breast cancer cell line
Dilip Kumar Saha, Subhash
Ekkehard Sinn & Chris Newton
284
Padhye*,
Synthesis, characterization and structure of
Ti(IV)
complexes
of
hydroxy-rich ligands
P Venkateshwara Rao, Erkki Kolehmainen &
Chebrolu P Rao*
290
Synthesis, characterization and thermal studies
of magnesium (II) complexes of ortho and paraaminobenzoic acids
The synthesis and spectroscopic characterization of ortho
or para-aminobenzoate complexes of Mg(II) namely
[Mg(H2O)6](X)2.2H2O (X=2-aminobenzoate (2-aba) 1 and
X=4-aminobenzoate (4-aba) 2). Compound 2 can be
reversibly dehydrated unlike 1
B R Srinivasan*, Sarvesh C Sawant &
Sunder N Dhuri
297
Structural chemistry and thermal properties of
some pyrimidine complexes
A few complexes of Fe(III), Co(II), Ni(II) and Cu(II) with
uracil, 6-amino uracil, and those with substituted phenyl
azo-6-amino uracils containing o-methyl, p-carboxy and ocarboxy substituents and 5,5-diethyl barbituric acid
sodium salt have been synthesized and characterized.
Mamdouh S Masoud* Saeda A Abou El Enein
& Hesham M Kamel
Notes
304
Surface properties and catalytic activity of
vanadia supported on samaria
Sm2O3 - vanadia catalysts have been prepared by wet
impregnation method using NH4VO3 solution and the
surface properties of the prepared catalysts have been
studied. It has been observed that the selectivity of the
products depends upon the composition of the supported
system.
S Sugunan* & N K Renuka
308
Photoelectrochemical
studies on thermally
Photoresponsive mixed metal chalcogenide films of (ZnCd)
treated (ZnCd) Se films
Se of desired composition have been prepared by
electrochemical codeposition and subjected to thermal
treatment. The thermally treated preparations have been
endowed with increased stability and somewhat improved
photoresponsiveness and they exhibit increased resistance
towards impairment due to electrochemical corrosion.
A K Shukla & Kaman Singh*
312
Apparent molar volume and apparent molar
compressibility of glycine in aqueous vanadyl
sulphate solutions at 298.15, 303.15 and 308.15
K
Apparent molar volume and apparent molar compressibility
of glycine in aqueous vanadyl sulphate solutions have been
determined. The negative transfer of volume has been
observed for 0.1 M and 0.05 M vanadyl sulphate solutions.
P G Rohankar & A S Aswar*
316
Kinetics of palladium(II) catalysed oxidation of
mercury(I) by iron(III)-2,2-bipyridyl complex
S A Chimatadar, S B Koujalagi & S T
Nandibewoor*
Fe(III)aq + 2(BipyH+)
Complex + Pd (II)
[Fe(Bipy)2]3+ + 2H+
(complex)
k


Pd(III) + FeII (bipy)3
… (2)
…(3)
slow
fast
 Hg (II) + Pd (II)
Pd(III) + Hg (I) 
… (4)
321
Kinetics and mechanism of the oxidation of
formic
and
oxalic
acids
by
tetrabutylammonium tribromide
Jaya Gosain & Pradeep K Sharma*
325
Kinetics and mechanism of dissolution
and transformation of chloropinnoite in
water at 293-313K
The influence of temperature (293-313K) and stirring rate
on the kinetics of dissolution and transformation of
chloropinnoite (2MgO·2B2O3·MgCl2·14H2O) in water have
been studied. The experimental results show that
chloropinnoite dissolves incongruently in water.
Zhihong Liu*, Mancheng Hu, Shiyang Gao &
Shuping Xia
330
Study on the supramolecular inclusion complex
of -cyclodextrin with retinoic acid
Inclusion compound of retinoic acid with -cyclodextrin
has been prepared by coprecipitating method and the
Yanling Zhang, Kaijun Liao, Weisheng Liu &
Xueyi Ma*
333
structure of resulting product has been characterized. The
results indicate that the formed supramolecule selfassembles in aqueous solution in the molar ratio 2:1 (host:
guest)
Synthesis and characterization of epoxy resin
in the presence of p-acetylbenylidene
triphenylarsoniumylide-mercuric
chloride
complex
Saurabh Pandey & A K Srivastava*
339
Synthesis, magnetic and spectral studies of
some new mixed-ligand nitrosyl complexes of
chromium(I)
R C Maurya*, A Pandey & R Verma
342
Synthesis
and
characterization
of
chlorodibenzyltin(IV) complexes with N,Ndialkyl dithiocarbamate ligands and crystal
structure of (PhCH2)2SnCl(S2CNMe2)
Handong Yin*, Chunlin Ma & Yong Wang
346
A new single pulse method for the
measurements of photosensitized singlet oxygen
quantum yield
R Venkatesan*, S Tamijselvy, N Periasamy,
T M Rajendiran, P S Rao & T S Srivastava
350
A new simpler relative method for estimating
photosensitized singlet oxygen quantum yield has been
developed. In this method a strong depletion signal is
observed when porphyrin (2 M) and 1,3diphenylisobenzofuran (DPBF, 500 M) are irradiated
using second harmonic 532 nm Nd-YAG laser pulse and
monitored at 410 or 415 nm by a ultraviolet filtered white
light.
Announcements
Authors for correspondence are indicated by (*)
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 245-253
Developments of water electrolysis technology by solid polymer
electrolyte
Sang-Do Han, Kee-Bae Park, Ravi Rana & K C Singh
Water electrolysis by solid polymer electrolyte is the most promising technology for large-scale hydrogen
production for future. The concept introduced by General Electric Co. (U.S.A) in late sixties has been adopted by
Brown Boveri Research Center, Baden, Switzerland and more recently by Japan under WE-NET Japanese Hydrogen
Programme Project. For the last 25 years, this field has witnessed a lot of activity, in research and development of
energy efficient water electrolyzers. In this review, the selection of high activity electrocatalysts, methods to prepare
SPE electrocatalyst composites, their stability, the pretreatment of solid polymer electrolyte membrane for the
deposition of electrocatalysts, the fabrication of current collectors, the scale up of water electrolyzers and recent
advances has been discussed.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 254 -258
Direct determination of the He–Kr interaction potential from the
extended
principle of corresponding states
Elaheh K Goharshadi & Majid Moinossadati
The pair potential energy function of He–Kr has been determined using a direct inversion of the experimentally
reduced viscosity collision integrals obtained from the corresponding-states correlation. The potential is in good
agreement with the previously determined potential. The resulting potential has been used to predict the viscosity and
diffusion coefficients of He-Kr binary mixtures and they are found to be in good agreement with the experiment.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 259 -265
Para-selective ethylation of t-butylbenzene with diethyl carbonate over
mesoporous molecular sieves
V Umamaheswari, M Palanichamy, Banumathi Arabindoo & V Murugesan
The vapour phase ethylation of t-butylbenzene (t-BB) with diethyl carbonate has been studied over
mesoporous Al-MCM-41 (Si/Al = 50 and 90) and Al, Mg-MCM-41 [Si/(Al+Mg) = 50] from 200 to 400ºC. The
products are benzene, ethylbenzene (EB), p-diethylbenzene (p-DEB), p-t-butylethylbenzene (p-tBEB) and p-tbutylvinylbenzene (p-tBVB) . t-Butylbenzene conversion increases with increase in temperature up to 300ºC, but
above this temperature it decreases. Ortho and meta-products are completely absent. Ethylbenzene is the product of
ethylation of benzene and cracking of p-tBEB.The selectivity of para-t-butylated products is favoured at lower
temperature while higher temperature favoures ethylbenzene selectivity. The influence of time on stream is examined
over Al-MCM-41 (50) and the results are discussed in this paper.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 266 -269
Refractive indices of binary liquid mixtures of (decane + benzene) and
(hexadecane + benzene, or + hexane) at 303.15, 308.15 and 313.15 K
S C Bhatia, Neelima Tripathi & G P Dubey
Refractive indices at 303.15, 308.15 and 313.15K have been measured for the binary liquid mixtures of (decane
+ benzene), and (hexadecane + benzene, or + hexane) over the entire composition range. From the experimentally
measured values, refractive index deviations at different temperatures have been computed and fitted to the RedlichKister polynomial equation to derive the binary coefficients and standard errors. Using various mixing rules,
refractive indices of the binary liquid mixtures at 298.15K have been calculated theoretically and the results
discussed in terms of average percentage deviations.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 270 -278
Kinetics and mechanism of permanganate oxidation of phenylphosphinic
acid
in acid perchlorate solution
Kamla Sharma & Raj Narain Mehrotra
The stoichiometry of the title reaction is expressed by the Equation, MnO 4 + 2C6H5HP(O)OH + 4H+ Mn(III)
+ 2C6H5PO(OH)2 + 2H2O. The kinetics and the rapid scan of the reaction mixture suggest the formation of the
complexes by C6H5HP(O)OH(C1, K1) and C6H5HP(O)O (C2, K2) with MnO4 ion. The equilibrium constants of the
complexes are H+ dependent. It is suggested that the complexes are formed by hydrogen bonds, P-H …. O-Mn, and
the redox involve the dissociation of H from the PH bond causing transfer of two electrons from substrate to
MnO4 through O bridge. The relative stability of the complex C2 > C1 because K1 < K2 and, k1 > k2 where k1 and
k2 are the rate constants for the decomposition of the complexes C1 and C2. The kinetics in perchlorate solution ( =
1 mol dm3, LiClO4) under pseudo-first order conditions ([PPA]  [MnO4]) indicated that the H+ catalysed rate
correlates with the expression kobs(Ka + [H+]) = a + b[H+] + c[H+]2 where kobs is the pseudo-first order rate constant
and Ka is the dissociation constant of C6H5HP(O)OH. The [H+]2 term is likely due to the acid catalysis of C1. The
activation parameters corresponding to k1 and k2 are reported.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 279 -283
Synthesis, structure, spectroscopy and antitumor activity of hydroxy
naphthoquinone thiosemicarbazone and its metal complexes
against MCF-7 human breast cancer cell line
Dilip Kumar Saha, Subhash Padhye, Ekkehard Sinn & Chris Newton
Coordinately unsaturated metal complexes of the stoichiometry [M(HL)Cl] and [Fe(HL)Cl 2].2H2O have been
isolated (where M=Cu(II), Ni(II), Pd(II) and Pt(II); HL=tridentate anion of H 2L 3). The X-ray crystal structure for 4hydroxy-3-methyl-1,2-naphthoquinone-1-thiosemicarbazone, 3 has been determined which crystallizes in space
group P21/c, a = 7.430(3), b = 10.794(3), c = 17.216(5) Å,  =92.91(3)o, Z = 4, and have ‘E’ configuration. The
Cu(II) 3a, Ni(II) 3c, Pd(II) 3d and Pt(II) 3e complexes are found to possess square planar geometries, whereas Fe(III)
complex 3b possesses a square pyramidal configuration. The in vitro activity of the synthesized compounds
examined against human breast cancer cell line MCF-7 clearly indicates that metal complexation enhances antitumor
activity, the highest being for the copper complex 3a.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 284 -289
Synthesis, characterization and structure of Ti(IV) complexes of
hydroxy-rich ligands
P Venkateshwara Rao, Erkki Kolehmainen & Chebrolu P Rao
Coordination chemistry of two multi-hydroxy rich ligands has been explored with Ti(IV) by isolating the resultant
products followed by their characterization. One of the products is also structurally characterized by single crystal
XRD.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 290 –296
Synthesis, characterization and thermal studies of magnesium (II)
complexes of ortho and para-aminobenzoic acids
B R Srinivasan, Sarvesh C Sawant & Sunder N Dhuri
The reaction of magnesium carbonate with ortho or para-aminobenzoic acid results in the formation of the
complexes [Mg(H2O)6](X)2.2H2O (X=2-aminobenzoate (2-aba) 1 and X=4-aminobenzoate (4-aba) 2). The 2aminobenzoate complex 1 has been characterised by metal analysis, isothermal weight loss studies, infrared, UV-Vis,
1H and 13C NMR spectra and X-ray powder diffraction. The 2-aba complex is relatively unstable as compared to the
corresponding 4-aba analogue and slowly decomposes to [Mg(2-aba)2] with the loss of water molecules. This
irreversible change is attributed to the disposition of the –NH2 group with respect to the carboxylate group in the sixmembered ring.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 297 –303
Structural chemistry and thermal properties of some pyrimidine complexes
Mamdouh S Masoud, Saeda A Abou El Enein & Hesham M Kamel
A few complexes of Fe(III), Co(II), Ni(II) and Cu(II) with uracil, 6-amino uracil, and those with substituted
phenyl azo-6-amino uracils containing o-methyl, p-carboxy and o-carboxy substituents and 5,5-diethyl barbituric
acid sodium salt have been synthesized and characterized by elemental analysis, magnetic moment and spectral
measurements (IR, UV-vis, ESR). The IR spectra show that uracil exists in keto- enol tautomerism but 6-amino
uracil possesses the keto amino-imine structure with some enol form. The iron complexes are with Oh geometry,
while the cobalt complexes are with different geometries (square planar and Oh). The square planar copper complexes
exist in ligand bridged structures. The nickel complexes are of tetrahedral configuration. In general, the azo group is
involved in the structural chemistry of the azo complexes. The coordination bond length has been calculated. The
thermal properties (TG and DTA) of the compounds and their complexes are measured and discussed and also the
thermodynamic parameters are evaluated.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 304-307
Surface properties and catalytic activity of vanadia supported on samaria
S Sugunan & N K Renuka
Sm2O3 - vanadia catalysts have been prepared by wet impregnation method using NH4VO3 solution. The surface properties of
the prepared catalysts have been studied using FTIR, XRD, surface area and pore volume data. The acid-base properties of the
system have been investigated by titrimetric method using Hammett indicators, adsorption of electron acceptors as well as
decomposition of cyclohexanol. Phenol alkylation reaction by methanol has been carried out to investigate the catalytic activity. It
has been observed that the selectivity of the products depends upon the composition of the supported system.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 308-311
Photoelectrochemical studies on thermally treated (ZnCd) Se films
A K Shukla & Kaman Singh
Photoresponsive mixed metal chalcogenide films of (ZnCd) Se of desired composition have been prepared by electrochemical
codeposition and subjected to thermal treatment at 400C in argon atmosphere under controlled conditions. Photoresponsiveness
of thermally treated electrodes has been examined employing I-3 / I2 redox system and characterised by photoaction spectral (PAS)
studies and impedance measurements. Thermal treatment of the electrodeposits is accompanied by inversion from p-to n-type
semiconductivity and they exhibit somewhat lowered band gap perhaps due to recrystallisation. The thermally treated preparations
have been endowed with increased stability and somewhat improved photoresponsiveness and they exhibit increased resistance
towards impairment due to electrochemical corrosion.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 312-315
Apparent molar volume and apparent molar compressibility of glycine in aqueous
vanadyl sulphate solutions at 298.15, 303.15 and 308.15 K
P G Rohankar & A S Aswar
Apparent molar volume and apparent molar compressibility of glycine in aqueous vanadyl sulphate solutions (0.10, 0.05 and
0.01 M) have been determined from 298.15 K to 308.15 K. The transfer of volumes for the transfer of glycine from water to
aqueous vanadyl sulphate have been evaluated. Negative transfer of volume has been observed for 0.1 M and 0.05 M vanadyl
sulphate solutions. The results are explained on the basis of electrostriction.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 316-320
Kinetics of palladium(II) catalysed oxidation of mercury(I) by iron(III)-2,2-bipyridyl
complex
S A Chimatadar, S B Koujalagi & S T Nandibewoor
Kinetics of oxidation of mercury(I) by iron(III)-2,2-bipyridyl in the presence of microamounts of palladium(II) has been
studied spectrophotometrically in aqueous nitric acid and methanol media. The reaction exhibits first order each in [iron(III)-2,2bipyridyl] and [palladium(II)] and zero order in [mercury(I)]. Increase in [HNO 3] decreases the reaction rate. Added products do
not have any significant effect on the reaction rate. A suitable reaction mechanism is proposed and the reaction constants of the
different steps involved have been evaluated.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 321-324
Kinetics and mechanism of the oxidation of formic and oxalic acids by
tetrabutylammonium tribromide
Jaya Gosain & Pradeep K Sharma
Kinetics and mechanism of oxidation of formic and oxalic acids by tetrabutylammonium tribromide (TBATB) have been
studied in 1:1 (v/v) acetic acid-water solutions. The main product of oxidation is carbon dioxide. The reaction is first order with
respect to TBATB. Michaelis-Menten type of kinetics has been observed with respect to the reductants. The oxidation of deuterioformic acid exhibits a substantial primary kinetic isotope effect (kH/kD = 5.85 at 298 K). The reaction has been studied in
solvents of different compositions of acetic acid and water. The solvent composition effect has been analysed using GrunwaldWinstein equation. Suitable mechanisms have been proposed.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 325-329
Kinetics and mechanism of dissolution and transformation of chloropinnoite in
water at 293-313K
Zhihong Liu, Mancheng Hu, Shiyang Gao & Shuping Xia
The influence of temperature (293-313K) and stirring rate on the kinetics of dissolution and transformation of chloropinnoite
(2MgO·2B2O3·MgCl2·14H2O) in water have been studied. According to the kinetic c-t curve and pH-t curve, the process of
dissolution and phase transformation can be divided into three stages: dissolution, transformation induce dissolution, and
crystallization stage. The experimental results show that chloropinnoite dissolves incongruently in water. MgCl 2 is removed first
and then the midproduct(MgO·B2O3·4H2O ) is formed. The final phase transformation product is inderite (2MgO·3B2O3·15H2O).
The kinetic equations of dissolution and crystallization have been obtained. The kinetic mechanisms of dissolution and
crystallization reactions have been confirmed according to order of reaction, activation energy and effect of stirring.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 330-332
Study on the supramolecular inclusion complex of -cyclodextrin with retinoic acid
Yanling Zhang, Kaijun Liao, Weisheng Liu & Xueyi Ma
Inclusion compound of retinoic acid with -cyclodextrin has been prepared by coprecipitating method and the structure of
resulting product studied by elemental analysis, phase solubility diagram, differential scanning calorimetry (DSC) analysis, FTIR
and NMR spectroscopy as well as X-ray diffractometry. Results indicate that the formed supramolecule self-assembles in aqueous
solution in the molar ratio 2:1 (host: guest).
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 333-338
Synthesis and characterization of epoxy resin in the presence of p-acetylbenylidene
triphenylarsoniumylide-mercuric chloride complex
Saurabh Pandey & A K Srivastava
p-Acetylbenzylidene triphenylarsoniumylide mercuric chloride complex modifies and also has autocatalytic curing properties
for epoxy resin. The degree of cure (), percentage crystallinity and glass transition temperature (Tg) of the modified resin,
investigated by differential scanning calorimetry, are 1.03, 91% and 298C respectively. The TGA technique has been used to
calculate the activation energy and the order of reaction, which are 97 kJ/mol and one respectively. The SEM analysis shows
presence of Hg (40%) in the epoxy resin.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 339-341
Synthesis, magnetic and spectral studies of some new mixed-ligand nitrosyl complexes of
chromium(I)
R C Maurya, A Pandey and R Verma
The synthesis and characterization of some new mixed-ligand nitrosyl chromium(I) complexes (having {CrNO}5* electron
configuration) of the general formula [Cr(NO)(acac)2(L)], [where L = benzothiazole (BZT), 2-(2-pyridyl)benzimidazole (PBZL),
2-hydroxymethylpyridine (2-HMP), 3-hydroxymetlylpyridine (3-HMP), o-anisidine (ANS) or N,N'-dimethylaniline (NNDA)]
have been carried out. The compounds having chromium(I) in a low-spin d5 configuration have been characterized by elemental
analyses, molar conductance, TGA, magnetic measurements, electron spin resonance and infrared spectral studies.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 342-345
Synthesis and characterization of chlorodibenzyltin(IV) complexes with N,Ndialkyl dithiocarbamate ligands and crystal structure of (PhCH2)2SnCl(S2CNMe2)
Handong Yin, Chunlin Ma & Yong Wang
Thirteen chlorodibenzyltin(IV) complexes with N,N-dialkyl dithiocarbamate ligands have been synthesized by the reaction of
dibenzyltin dichloride with N,N-dialkyl dithiocarbamates in 1:1stoichiometry and characterized by elemental analysis, UV, IR and
1H NMR. The crystal structure of (PhCH ) SnCl(S CNMe has been determined by X-ray single crystal diffraction. The
2 2
2
2
crystallographic data are as follows: triclinic, space group P-1, a=7.5750(15) Å, b=10.615(2) Å, c=12.059(2) Å, =95.053(3),
=95.539(4),=99.113(4), Z=2, V=947.6(3) Å, Dx=1.600g/ cm-3, =1.705mm-1, F(000)=456, R1=0.0409, wR2=0.1194(I2(I).
The structures consist of discrete molecules containing five-coordinate tin atoms in a seriously distorted tigonal bipyramidal
configuration. The molecules are packed in the unit cell as weakly-bridged dimmers.
Indian Journal of Chemistry
Vol. 41A, February 2002, pp. 346-349
A new single pulse method for the measurements of photosensitized singlet oxygen
quantum yield
R Venkatesan, S Tamijselvy, N Periasamy, T M Rajendiran, P S Rao & T S Srivastava
A new simpler relative method for estimating photosensitized singlet oxygen quantum yield has been developed. In this method
a strong depletion signal is observed when porphyrin (2 M) and 1,3-diphenylisobenzofuran (DPBF, 500 M) are irradiated using
second harmonic 532 nm Nd-YAG laser pulse and monitored at 410 or 415 nm by a ultraviolet filtered white light. The observed
depletion is attributed to the reaction of DPBF with sensitized singlet oxygen. The amplitude of the depletion signal is related
directly to the singlet oxygen sensitization yield. Appropriate kinetic equations have been derived to relate the change in the
absorbance of DPBF and singlet oxygen quantum yield. The singlet oxygen quantum yields of fifteen porphyrins and
metalloporphyrins have been investigated in dimethylformamide solution. The results are compared with the quantum yields
obtained by the usual kinetic run experiments. The results are found to match exceedingly well in the two methods.