Indian Journal of Chemistry

Sect. A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical

CODEN: ICACEC; ISSN: 0376-4710 (Print), 0975-0975 (Online)

http://www.niscair.res.in; http://nopr.niscair.res.in

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VOLUME 51A

NUMBER 7

July 2012

 

CONTENTS

 

 

911

 


Quantum chemical investigations on determination of electronic, structural and electric properties of some even carbon cage fullerenes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

F E Jorge*,  M K Morigaki & Sara S Jorge

 

 

 

Electronic structures and geometries of even carbon cage fullerenes in gas phase are investigated at the B3LYP/DZP level of theory. The extra stability of C60 is confirmed by the shorter mean bond length, smaller angle strain, and widest energy gap. From optimized geometries and using non-hybrid and hybrid functionals along with the AXZP (X = D, T, and Q) basis sets, static dipole polarizabilities of C20, C24, C26, C28, C30, C32, C36, C38, C44, C50, C60, and C70 are evaluated.

 

 

 

 

917

 

Synthesis and characterization of arylazoimidazolium iodide and tetraiodocadmium(II) compounds

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D Mallick, R Saha, K K Sarker, P Datta & C Sinha*

 

 

 

Single crystal X-ray structures of 1,3-dialkyl-2-(arylazo)-imidazolium iodide and 1,3-dialkyl-2-(arylazo)imidazolium tetraiodocadmium(II) show the formation of cationic core of organic motif and the anions, I or [CdI4]2- positioned comfortably by ionic forces, p---p, C–H---p and C–H---I interactions.
DFT computations have been used to explain the electronic structure and the electronic spectra of the compounds.

 

 

 

 

 

Notes

 

927

 

Preparation and characterization of high surface area
α-AlF3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Hongbo Yu, Wenzhi Jia, Yuejuan Wang, Jiqing Lu & Mengfei Luo*

 

 

 

Well crystallized α-AlF3 with high surface area (66 m2 g-1) is synthesized by a carbon template method. Temperatures for fluorination and thermal combustion are crucial for the phase composition of the resulting sample.   

 

 

 

a: Loading carbon in hard template;

b: fluorination with gaseous HF;

c: Combusting carbon template with oxygen

 

 

931

 

Effect of glycine concentration on the properties of LaCoO3 perovskite prepared by the glycine-nitrate process

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Rajender R Kondakindi

 

 

 

LaCoO3 perovskite (58 – 69 nm) has been prepared by glycine-nitrate method. The effect of concentration of glycine on the particle size, crystal structure and reducibility is studied.

 

 

 

 

 

 

 

937

 

 

 

 

 

 

 

 

Synthesis of new iridium complexes with substituted 1,3,4-oxadiazole and β–diketones as ligands for OLED application

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Amit Kumar, Ritu Srivastava*,
Modeeparampil  N Kamalasanan & Ishwar Singh

 

 

 

Cyclometalated iridium complexes bearing octyloxy substituted 1,3,4-oxadiazole derivatives are synthesized. Green and orange-emitting OLEDs are fabricated using these complexes
as the dopants. Color tuning due to secondary ligand has
also been studied.

 

 

 

 

 

 

 

 

 

 

 

943

 

Copper modified iron oxide as heterogeneous photo-Fenton reagent for the degradation of coomasie brilliant blue R-250

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Noopur Ameta, Jyoti Sharma, Sanyogita Sharma, Sudhish Kumar & Pinki B Punjabi*

 

 

 

Heterogeneous photo-Fenton degradation of coomasie brilliant blue R-250 has been carried out with modified iron oxide under visible light. Under optimal conditions in the presence of
Cu modified Fe2O3, rate of degradation of the dye is found to be
3.07 × 10‑4 s-1, while in presence of pure Fe2O3 the rate of photo-Fenton degradation is found to be 2.16 x 10-4 s-1.

 

 

 

 

 

 

 

949

 

 

Kinetic study of oxidation of nitrite with a metallo superoxide

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sekhar Gain, Subrata Mukhopadhyay* &
Rupendranath Banerjee
*

 

 

 

The superoxide ligand in [(en)(dien)CoIII(O2)CoIII(en)(dien)]5+ oxidises N(III) in parallel paths, viz., electron transfer from NO2- and proton coupled electron transfer from HNO2. The ancillary ligands have considerable effect on the redox behavior of superoxide ligand.

 

 

 

 

 

955

 

Guide to Authors

 

 

 

 

 

Authors for correspondence are indicated by (*)

 

 

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 911-916

 

Quantum chemical investigations on determination of electronic, structural and electric properties of some even carbon cage fullerenes

F E Jorgea, *, M K Morigakib & Sara S Jorgea

aDepartamento de Física, Universidade Federal do Espírito Santo, 29060-900 Vitória, ES, Brazil

Email: jorge@cce.ufes.br

bDepartamento de Química, Universidade Federal do Espírito Santo, 29060-900 Vitória, ES, Brazil

Received 13 March 2012; revised and accepted 11 June 2012

The electronic structures and geometries of even carbon cage fullerenes in gas phase are investigated at the B3LYP/DZP level of theory. The potential relationship between geometric factors and stability is systematically examined. The extra stability of C60 has been confirmed by the shorter mean bond length, smaller angle strain, and widest energy gap. From optimized geometries and using non-hybrid and hybrid functionals along with the AXZP (X = D, T, and Q) basis sets, static dipole polarizabilities of C20, C24, C26, C28, C30, C32, C36, C38, C44, C50, C60, and C70 are evaluated.

Keywords: Fullerenes, Electronic structures, Geometry, Stability, Electric properties, Density functional calculations

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 917-926

 

Synthesis and characterisation of arylazoimidazolium iodide and tetraiodocadmium(II) compounds

 

D Mallicka, R Sahab, K K Sarkerc, P Dattad & C Sinhae, *

aDepartment of Chemistry, Mrinalini Datta Mahavidyapith, Birati, Kolkata 700 051, West Bengal, India

bDepartment of Physics, Jadavpur University, Kolkata 700 032, West Bengal, India

cDepartment of Chemistry, Mahadevananda Mahavidyalaya, Barrackpore, Monirampore, Kolkata 700 120, West Bengal, India

dCalcutta Institute of Engineering and Management, 24/1A Chandi Ghosh Road, Kolkata 700 040, West Bengal, India

eDepartment of Chemistry, Inorganic Chemistry Section, Jadavpur University, Raja Suboth Mullick Road,
Kolkata 700 032, West Bengal, India

Email: c_r_sinha@yahoo.com

Received 9 January 2012; revised and accepted 22 June 2012

Sixteen new inorganic-organic hybrid compounds of 1,3-dialkyl-2-(arylazo)imidazolium, [RaaiR/R//]+ (R, alkyl group), and I- or [CdI4]2- as counter ion are synthesized and characterized by spectroscopic (IR, UV-vis, 1H NMR) techniques. The single crystal X-ray diffraction studies of representative compounds, viz.,
1,3-dimethyl-2-(p-tolylazo)imidazolium iodide [MeaaiMe2+]I- and bis- [1-methyl-3-benzyl-2-(p-tolylazo)-imidazolium]tetraiodocadmium(II) [Meaai(Me)CH2Ph+]2 [CdI4]2-, have confirmed the proposed structures. DFT computation has been used to explain the electronic structure and the electronic spectra of the compounds.

Keywords:   Coordination compounds, Inorganic-organic hybrids, Cadmium, Dialkyl-arylazoimidazolium salts, Arylazoimidazolium salts, Iodometallates, X-ray structures, Density functional calculations

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 927-930

 

Preparation and characterization of high surface area α-AlF3

Hongbo Yu, Wenzhi Jia, Yuejuan Wang, Jiqing Lu & Mengfei Luo*

Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004, PR China
Email: mengfeiluo@zjnu.cn

Received 24 September 2011; revised and accepted 22 June 2012

High surface area a-AlF3 has been prepared by a carbon hard template method, Wherein γ-Al2O3 is immersed with sucrose aqueous solution and the dried mixture thermally treated under N2 flow at 450 oC to obtain the C@γ-Al2O3. C@γ-Al2O3 can be completely transformed to C@a-AlF3 with hydrogen fluoride at
400 oC. After the carbon template in C@
a-AlF3 is removed by high temperature combustion, a high surface area a-AlF3 (66 m2 g-1) is obtained. It is found that the fluorination process is crucial for the resulting a-AlF3. Although high fluorination temperature is favourable to the formation of a-AlF3, it also results in the decline of surface area.

Keywords: High surface area, Fluorination, Raman spectra Crystal structure, Aluminium fluoride

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 931-936

 

Effect of glycine concentration on the properties of LaCoO3 perovskite prepared by the glycine-nitrate process

Rajender R Kondakindi

College of Science, Technology, Engineering and Mathematics, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA

Email: rajender.kondakindi@gmail.com

Received 12 July 2011; revised and accepted 20 June 2012

LaCoO3 nanocrystals have been prepared by the glycine-nitrate process. The effect of glycine content in the synthesis solution on various properties of LaCoO3 has been studied in the glycine-to-nitrate molar ratio between 0.75 and 2.0. The samples are characterized by X-ray diffraction for phase purity and particle size, by transmission electron microscopy for particle size, by BET for surface area and by temperature-programmed reduction for reducibility of Con+. XRD reflections show the presence of impurities in the as-prepared samples while only rhombohedral phase could be identified in the samples after calcination at 700 °C. For all the glycine-to-nitrate ratios tested, the particle size estimated from XRD data ranges from 58-69 nm, which are systematically lower than those determined by BET which ranged from 97-118 nm. TPR profiles of the samples show two major peaks; one due to the reduction of Co3+ to Co2+ and the other due to the reduction of Co2+ to Co0. The samples prepared under fuel-deficient and fuel-rich conditions show higher reducibility as compared to that of the sample prepared under stoichiometric conditions.

Keywords: Glycine-nitrate process, Perovskites, Mixed oxides, Lanthanum cobaltate, Surface area, Particle size

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 937-942

 

Synthesis of new iridium complexes with substituted 1,3,4-oxadiazole and β–diketones as ligands for OLED application

Amit Kumara, b Ritu Srivastavaa, *, Modeeparampil N Kamalasanana & Ishwar Singhb

aCenter for Organic Electronics (OLED Lab), CSIR-National Physical Laboratory,
Dr K S Krishnan Road, New Delhi 110 012, India

Email: ritu@mail.nplindia.ernet.in

bDepartment of Chemistry, MD University, Rohtak 124 001, Haryana, India

Received 13 October 2011; revised and accepted 20 June 2012

New iridium(III) complexes, viz., (OctOXD)2Ir(tta) and (OctOXD)2Ir(tmd) [OctOXD = 2-(4-butyloxyphenyl)-5-phenyl-[1,3,4]oxadiazolato-N4,C2, tta = 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione, tmd = 2,2,6,6-tetramethylheptane-3,5-dione] have been synthesized and characterized. These complexes have two cyclometalated ligands (C^N) and a bidentate diketone ligand {[(C^N)2Ir(X)], where X is a β-diketone with trifloromethyl, theonyl or t-butyl groups} and show good thermal stability in air up to 400 oC. The photoluminescence spectra of the two complexes show peak emissions at 537 and 557 nm, respectively. The electroluminescent properties of these complexes have been studied by fabricating multilayer devices. The lectroluminescence spectra also show peak emission at 541 and 564 nm for (OctOXD)2Ir(tta) and (OctOXD)2Ir(tmd), respectively.

Keywords: Electroluminescence, Light emitting diodes, Organic light emitting diodes, Diodes, Cyclometallated complexes, Iridium, β-Diketones

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 943-948

 

Copper modified iron oxide as heterogeneous photo-Fenton reagent for the degradation of coomasie brilliant blue R-250

Noopur Ametaa, Jyoti Sharmaa, Sanyogita Sharmaa, Sudhish Kumarb & Pinki B Punjabia, *

aPhotochemistry Laboratory, Department of Chemistry,University College of Science, M L Sukhadia University,
Udaipur 313 002, Rajasthan, India

Email: pb_punjabi@yahoo.com

bDepartment of Physics, University College of Science, M L Sukhadia University, Udaipur 313 002, Rajasthan, India

Received 9 August 2011; revised and accepted 25 June 2012

The heterogeneous photo-Fenton degradation of coomasie brilliant blue R–250 under visible light has been investigated using copper modified iron oxide, which has been prepared by coprecipitation method and characterized by IR spectroscopy, scanning electron microscopy and X-ray diffraction. The rate of photocatalytic degradation of dye follows pseudo-first order kinetics. The effects of various parameters like pH, concentration of dye, amount of photocatalyst, amount of H2O2 and light intensity on the rate of the photo-Fenton degradation has also been studied. Chemical oxygen demand of the reaction mixture before and after exposure has been determined. A tentative mechanism for the photocatalytic degradation has been proposed, wherein involvement of OH radicals has been confirmed by the drastic reduction in the reaction rate in the presence of OH radical scavengers such as isopropanol and butylated hydroxy toluene. The retardation with butylated hydroxy toluene is much higher than with isopropanol. Under similar conditions, efficiencies of Fe2O3 and copper modified Fe2O3 have been compared for the photocatalytic degradation of coomasie brilliant blue R-250.

Keywords: Photocatalysis, Degradation, Dye degradation, Photo-Fenton degradation, Iron oxide, Copper modified iron oxide

 

Indian Journal of Chemistry

Vol. 51A, July 2012, pp. 949-953

 

Kinetic study of oxidation of nitrite with a metallo superoxide

Sekhar Gaina, Subrata Mukhopadhyayb, * & Rupendranath Banerjeeb, *

aRamakrishna Mission Vidyamandira, Department of Chemistry, Belur Math, Howrah 711 202, India

bDepartment of Chemistry, Jadavpur University,
Kolkata 700 032, India

Email: smukhopadhyay@chemistry.jdvu.ac.in (SM)/
rupenju@yahoo.com (RB)

Received 29 March 2012; revised and accepted 26 June 2012

Bridging superoxide in [(en)(dien)CoIII(O2)CoIII(en)(dien)]5+ quantitatively oxidizes N(III) to N(V), itself being reduced to hydroperoxo group. Kinetic study and solvent isotope effect indicate two parallel paths:
(a) electron transfer and (b) proton coupled electron transfer. The present study also indicates that the ancillary ligands affect the reaction rate substantially. Studies on redox behavior of metal bound superoxide are not many and this study is expected to shed some light on the redox nature of metal bound superoxide.

Keywords: Kinetics, Reaction mechanisms, Oxidation, Metallo superoxides