Carbon clusters on substrate surface for graphene growth- theoretical and experimental approach.

Growth morphology of carbon clusters deposited on different substrates were investigated by theoretical and experimental approach. For theoretical approach, molecular dynamics was employed to evaluate an adsorptive stability of different size of carbon clusters placed on different substrates. The adsorptive stability was estimated by the difference of total energy of supercell designed as carbon cluster placed on a certain crystal plane of substrate.

Enhanced Ultrafast Nonlinear Optical Response in Ferrite Core/Shell Nanostructures with Excellent Optical Limiting Performance.

Nonlinear optical nanostructured materials are gaining increased interest as optical limiters for various applications, although many of them suffer from reduced efficiencies at high-light fluences due to photoinduced deterioration. The nonlinear optical properties of ferrite core/shell nanoparticles showing their robustness for ultrafast optical limiting applications are reported. At 100 fs ultrashort laser pulses the effective two-photon absorption (2PA) coefficient shows a nonmonotonic dependence on the shell thickness, with a maximum value obtained for thin shells.

ESR Study of (La,Ba)MnO/ZnO Nanostructure for Resistive Switching Device.

Structure, electric, and resonance properties of (La,Ba)MnO/ZnO nanostructure grown on SrTiO (001) substrate have been investigated. It is found that at room temperature and relatively low voltages (|V |< 0.2 V), the structure shows good rectification behavior with rectification factor near 210.

Synthesis and spectroscopic characterization of copper zinc aluminum nanoferrite particles.

Copper doped zinc aluminum ferrites CuxZn1-x.(AlxFe2-x)O4 are synthesized by the solid-state reaction route and characterized by XRD, TEM, EPR and non linear optical spectroscopy techniques. The average particle size is found to be from 35 to 90nm and the unit cell parameter "a" is calculated as from 8.

Synthesis and spectroscopic characterization of magnesium oxalate nano-crystals.

Synthesis of MgC92)O(4)⋅2H(2)O nano particles was carried out by thermal double decomposition of solutions of oxalic acid dihydrate (C(2)H(2)O(4)⋅2H(2)O) and Mg(OAc)(2)⋅(40H(2)O employing CATA-2R microwave reactor. Structural elucidation was carried out by employing X-ray diffraction (XRD), particle size and shape were studied by transmission electron microscopy (TEM) and nature of bonding was investigated by optical absorption and near-infrared (NIR) spectral studies. The powder resulting from this method is pure and possesses distorted rhombic octahedral structure.

Spectroscopic characterization of manganese minerals.

Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.

Electron paramagnetic resonance, optical absorption and Raman spectral studies on a pyrite/chalcopyrite mineral.

Pyrite and chalcopyrite mineral samples from Mangampet barite mine, Kadapa, Andhra Pradesh, India are used in the present study. XRD data indicate that the pyrite mineral has a face centered cubic lattice structure with lattice constant 5.4179 Å.

EPR and optical absorption spectral studies on sphalerite mineral.

The mineral sphalerite (Zn,Fe)S has been characterized by a combination of X-ray diffraction, EPR and NIR spectroscopy. The optical absorption spectrum of mineral sphalerite is due to an iron impurity only, which is in a distorted octahedral environment. The g=2.

Spectroscopic and structural characterization of pascoite.

Pascoite mineral having yellow-orange colour of Colorado, USA origin has been characterized by EPR, optical and NIR spectroscopy. The colour dark red-orange to yellow-orange colour of the pascoite indicates that the mineral contain mixed valency of vanadium. The optical spectrum exhibits a number of electronic bands due to presence of VO(II) ions in the mineral.

Electron paramagnetic resonance, NIR studies on zoisite, clinozoisite and chrom-zoisite minerals.

A zoisite group of mineral samples from different localities are used in the present study. An EPR study on powdered samples confirms the presence of Mn(II), Fe(III) and Cr(III) in the minerals. NIR studies confirm the presence of these ions in the minerals.

EPR and optical absorption spectral studies on voglite mineral.

A voglite mineral sample of Volrite Canyon #1 mine, Frey Point, White Canyon Mine District, San Juan County, Utah, USA is used in the present study. An EPR study on powdered sample confirms the presence of Mn(II) and Cu(II). Optical absorption spectral results are due to Cu(II) which is in distorted octahedron.

Electron paramagnetic resonance, optical absorption, IR and Raman spectral studies on pelecypod shell.

Pelecypod shell originated from Kolleru lake of Andhra Pradesh is used in the present work. It contains Mn(II) and Fe(III) in traces. The EPR spectrum of the compound is due to Mn(II) which is in three independent sites.

Electron paramagnetic resonance and optical absorption spectral studies on chalcocite.

A chalcocite mineral sample of Shaha, Congo is used in the present study. An electron paramagnetic resonance (EPR) study on powdered sample confirms the presence of Mn(II), Fe(III) and Cu(II). Optical absorption spectrum indicates that Fe(III) impurity is present in octahedral structure whereas Cu(II) is present in rhombically distorted octahedral environment.