Government Arts College for Women Autonomous

Pudukkottai, India

Government Arts College for Women Autonomous

Pudukkottai, India

Time filter

Source Type

Sajan D.,Bishop Moore College | Devi T.U.,Government Arts College for Women Autonomous | Safakath K.,Raman Research Institute | Philip R.,Raman Research Institute | And 2 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

FT-IR, FT-Raman and UV-Vis spectra of the nonlinear optical molecule ninhydrin have been recorded and analyzed. The equilibrium geometry, bonding features, and harmonic vibrational wavenumbers have been investigated with the help of B3LYP density functional theory method. A detailed interpretation of the vibrational spectra is carried out with the aid of normal coordinate analysis following the scaled quantum mechanical force field methodology. Solvent effects have been calculated using time-dependent density functional theory in combination with the polarized continuum model. Natural bond orbital analysis confirms the occurrence of strong intermolecular hydrogen bonding in the molecule. Employing the open-aperture z-scan technique, nonlinear optical absorption of the sample has been studied in the ultrafast and short-pulse excitation regimes, using 100 fs and 5 ns laser pulses respectively. It is found that ninhydrin exhibits optical limiting for both excitations, indicating potential photonic applications. © 2013 Elsevier B.V. All rights reserved.


Balachandran V.,Arignar Anna Government Arts College | Lakshmi A.,Hh The Rajahs College Autonomous | Janaki A.,Government Arts College for Women Autonomous
Journal of Molecular Structure | Year: 2012

In this study, the conformational stability of 2-hydroxy-4-methyl-3- nitropyridine and 2-hydroxy-4-methyl-5-nitropyridine has been analyzed, and vibrational analyses of the same have been carried out by the application of B3LYP/6-311++G basis set based on scaled quantum mechanical (SQM) method. Vibrational analyses of the most stable conformer of 2-hydroxy-4-methyl-3- nitropyridine and 2-hydroxy-4-methyl-5-nitropyridine are conducted by means of infrared absorption and Raman spectroscopy in combination with theoretical (DFT) simulations. The observed and simulated spectra agreed well. Molecular stability and bond strength were investigated by applying the natural bond orbital analysis (NBO). The calculated HOMO and LUMO energies show that charge transfer occurs in the molecules. Information about the size, shape, charge density distribution, and site of chemical reactivity of the molecules has been obtained by mapping electron density isosurface with electrostatic potential (ESP). © 2012 Elsevier B.V. All rights reserved.


Balachandran V.,Arignar Anna Government Arts College | Lakshmi A.,Hh The Rajahs College Autonomous | Janaki A.,Government Arts College for Women Autonomous
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2011

The FT-IR and FT-Raman spectra of 4,6-dichloro-2-(methylthio)pyrimidine (DMP) have been recorded and analyzed. The optimized geometry, intramolecular hydrogen bonding, and harmonic vibrational wave numbers of DMP have been investigated with the help of B3LYP density functional theory (DFT) method supplemented with 6-31G** basis set. The infrared and Raman spectra were predicted theoretically from the calculated intensities. Natural Bond Orbital (NBO) analysis of DMP has been performed to indicate the presence of intramolecular C-H⋯Cl hydrogen bonding. The formation of Lewis and non-Lewis orbitals and second-order perturbation energies of DMP have also been reported. © 2011 Published by Elsevier B.V. All rights reserved.


Gowri S.,Cauvery College for Women | Uma Devi T.,Government Arts College for Women Autonomous | Sajan D.,Bishop Moore College | Bheeter S.R.,St. Joseph's College | Lawrence N.,St. Joseph's College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2011

A new organic nonlinear optical material l-tryptophanium picrate was synthesized. From the powder XRD pattern the various planes of reflections were identified. The grown crystals were subjected to FT-IR and 1H NMR spectral analyses to confirm the synthesized compound. Thermal properties of the crystals were investigated using thermo gravimetric (TG) and differential thermal analyses (DTA). The second harmonic generation (SHG) efficiency of the title compound was found using the modified experimental setup of Kurtz and Perry. © 2011 Elsevier B.V. All Rights Reserved.


Gowri S.,Cauvery College for Women | Uma Devi T.,Government Arts College for Women Autonomous | Sajan D.,Bishop Moore College | Bheeter S.R.,St. Joseph's College | Lawrence N.,St. Joseph's College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2012

A new organic nonlinear optical material adenosinium picrate (C 10H 14N 5O 4 +, C 6 H 2 N 3 O 7 -) was synthesized. The single crystal X-ray diffraction revealed the non-centrosymmetric crystal structure, which is an essential criterion for second harmonic generation. The crystalline nature of the grown crystals was confirmed using powder XRD techniques. Molecular structure was confirmed by NMR spectral analysis and functional groups were identified by FT-IR spectral analysis. The optical transmittance window and the lower cutoff wavelength of the AP have been identified by UV-vis-NIR studies. Thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study its thermal properties. Powder test with Nd:YAG laser radiation shows second harmonic generation. © 2011 Elsevier B.V.


Ravichandran K.,P.A. College | Snega S.,P.A. College | Jabena Begum N.,P.A. College | Rene Christena L.,SASTRA University | And 2 more authors.
Philosophical Magazine | Year: 2014

ZnO nanopowders simultaneously doped with fluorine (20 at.%) and magnesium (4, 8, 12 and 16 at.%) (ZnO:F:Mg) have been synthesized using an inexpensive simple soft chemical route for the first time. The effect of Mg doping level on certain physical properties and antibacterial activities of ZnO:F:Mg nanopowders has been investigated and reported. XRD studies showed that the products have the hexagonal wurtzite structure of ZnO. Fourier transform infrared spectra authenticate the presence of MgO stretching vibration, which is responsible for the increased antibacterial activity of the synthesized samples. The antibacterial activity of ZnO:F:Mg nanopowders was found to be enhanced with increase in Mg doping level as it causes a reduction in the grain size. © 2014 Taylor & Francis.


Renuka Devi K.,Government Arts College for Women Autonomous | Gomathiyalini A.,Government Arts College for Women Autonomous
International Journal of ChemTech Research | Year: 2015

Ultrasonic velocity, density and viscosity of sodium chloride in aqueous sodium dodecyl sulphate (10 mm) solution at 298 ° K, 308 ° K, 318 ° K and 328 ° K have been measured. Using these experimental values, acoustical parameters such as adiabatic compressibility (β), intermolecular freelength (Lf), specific acoustic impedance (z), relaxation time (τ), relative association (RA), absorption coefficient (α/f2), acoustic attenuation and Lennard Jonne’s potential were calculated. These parameters are extensively used to illustrate the nature of interactions between component molecules. Various molecular informations and structural variations of sodium chloride solution with the anionic surfactant sodium dodecyl sulphate have been analyzed on the basis of the changes in the above parameters with concentration and temperatures. © 2015, Sphinx Knowledge House. All rights Reserved.


Dheivamalar S.,Government Arts College for Women Autonomous | Sugi L.,Government Arts College for Women Autonomous
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2015

Structures and stabilities of dodecahedral fullerene C19X (X = Ni, Ti) and C20 have been investigated by quantum chemical calculations based on density functional theory. The geometrical structures, relative stabilities, dielectric constant of the doped cages were studied systematically and compared with those of the fullerene C20 cage. A series of dodecahedral functionalized derivatives have been studied at the B3LYP/6-31G level of density functional theory (DFT). The relative and formation energies of compounds, Mulliken charges, occupancy, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), the HOMO-LUMO band gap and chemical potential (μ) were calculated. The doping effect is discussed in terms of the change in the CC bond length and total dipole moment. The obtained result indicates that the CC bond length increases as a result of doping. The NBO analysis showed that there is a hyper conjugative interaction between the hetero atoms such as titanium and nickel lone-pair electron of doped fullerene with bonding and antibonding (σ∗) orbital of carbon atom of fullerene. The stability of the molecule, arising from charge delocalization, has been analyzed using Natural Bond Orbital (NBO) analysis. The nucleus - independent that more negative NICS values in doped fullerene than those of C20. The condensed Fukui Function and the newly introduced the atomic descriptors S (fk) to determine the local reactive sites of the molecular systems during electrophilic, nucleophilic and radical attacks have been calculated for the fullerene C20 compound. © 2015 Elsevier B.V. All rights reserved.


Renuka Devi K.,Government Arts College for Women Autonomous | Gomathiyalini A.,Government Arts College for Women Autonomous
Journal of Chemical and Pharmaceutical Sciences | Year: 2015

Ultrasonic is a versatile and non-destructive technique and highly useful for the investigation of various physiochemical properties. Surfactants play an important role as cleaning, wetting, dispersing and emulsifying and foaming agents in many applications and products including detergents, fabric softeners. Sodium dodecyl sulphate, selected for present study is an anionic type surfactant extracted from inexpensive coconut and palm oils. In order to increase the efficiency of surfactant, detergent builders are used. Builders are used as water softeners, which binds and extracts the cations especially calcium and magnesium ions present in the wash solutions, thereby increasing the faster removal of stains from the clothes. Typical builders chosen are sodium carbonate and sodium silicate. Sodium carbonate can be used to remove grease, oil and tough stains by preventing the bonding of hard ions with detergent. Sodium silicate when used along with the detergent, their granules gain the ruggedness from a coating of silicates. This study is an attempt to find the better surfactant combination among the two builders. In recent years, the studies of acoustical parameters of solutions have been found to be useful in understanding the molecular interaction between the surfactant and builder molecules in the solutions. The accurate measurement of ultrasonic velocity, density and viscosity of builder solutions in aqueous sodium dodecyl sulphate (10 mm) solution at different temperatures and derived parameters such as adiabatic compressibility (β), intermolecular free length (Lf), specific acoustic impedance (z), relaxation time (t), relative association (RA), absorption coefficient (α/f2) will provide information regarding the various interactions. Correlating the strength and type of interaction between the surfactant and builder combinations, the stain removing capacity of the surfactant solutions can be interpreted. Though the adiabatic compressibility values for both the system decreases with respect to concentration, the fall in β is more in sodium silicate compared to sodium carbonate. This confers that, among the two builders used, sodium silicate which removes the stain by means of ion-exchange mechanism seems to be better than sodium carbonate which works by precipitating. Sodium silicate also decreases the corrosion inside the washer. This kind of study becomes important since it provides welfare for both human and environment.


Janaki A.,Government Arts College for Women Autonomous | Balachandran V.,Arignar Anna Government Arts College
Indian Journal of Pure and Applied Physics | Year: 2013

Vibrational spectral analysis of the non-linear optical (NLO) material, 2,6-dichloro-4-nitroaniline (DCNA) has been carried out by using FT-IR and FT-Raman spectroscopic techniques. The Hartree-Fock(HF) and Density Functional Theoretical (DFT) computations have been performed at 6-311++G** level to derive equilibrium geometry, vibrational wavenumbers, intensities and first order hyperpolarizability. The optimized geometry, various bonding features and harmonic vibrational frequencies of DCNA have been investigated. Vibrational bands to the various structural groups and their significance were investigated by analyzing the vibrational spectra. Vibrational analysis reveals that simultaneous IR and Raman activation to the phenyl ring modes also provide evidence for the charge transfer interaction between the donors and acceptor can make the molecule polarized and the intramolecular charge transfer interaction must be responsible for the NLO properties of DCNA. The Mulliken atomic charge analysis was also made in the present study. The dipole moment (μ), polarizability (α) and the hyperpolarizability (β) values of the investigated molecule have been computed using HF and B3LYP methods.

Loading Government Arts College for Women Autonomous collaborators
Loading Government Arts College for Women Autonomous collaborators