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A combination of the transmission electron microscopy and in situ Raman scattering approach is employed to explain the structural variation observed in the different phases of glassy sanbornite. The correlation existing between the nucleation trend and the observed structural variation of the system is also discussed.

A static pressure-induced decomposition of indium hydroxide into metallic indium that takes place at ambient temperature is reported. The results from angle-dispersive X-ray diffraction, transmission electron microscopy imaging, Raman scattering and FTIR spectroscopy confirmed that the partial decomposition of indium hydroxide into metallic indium is irreversible.

The article presents a new approach, which employs the single-crystal Ag seeds for the synthesis of the silver nanocubes with controllable edge lengths. A comparative analysis of their localized surface plasmon resonance and surface-enhanced Raman scattering properties is also presented.

The stability of carbon nanotubes (CNTs) under irradiation of a carbon ion beam of energy 55 MeV is described. The Raman results have shown the phenomenon of healing or annealing of CNTs under ion beam irradiation, where the annealing process has begun at the lowest value of fluences and has persisted for good range of fluence values.

Raman microscopy and refractive near-field profilometry are used for studying waveguides written in Yb-doped Kirge QX glass under the low repetition-rate (noncumulative-heating) regime. The results have shown that the mechanism of refractive index change in a particular type of glass is very different, depending on the irradiation conditions.

The stress developed in phosphorus-doped layers grown on (110)-textured polycrystalline diamond templates is examined. The shifts of the diamond Raman diffusion and the exciton recombination energies are followed by Raman and cathodoluminescence spectroscopies.

Zn[Se.sub.(1-x)][Te.sub.x] epilayers are grown on GaAs(001) substrates by isothermal closed space sublimation (ICSS) method. Raman and photoluminescence characterizations have shown the existence of random alloy epilayers with larger composition disorder in the mesoscopic scale than those obtained by molecular beam epitaxy.

An intense short pulse laser propagating through a heavily doped degenerate semiconductor has parametrically excited a free carrier space charge mode and back scattered electromagnetic mode via free carrier nonlinearity. Landau damping and collisional damping of the decay waves have determined the threshold for the instability.

An active molecular plasmonics system is shown where a supramolecular chromophore generated in a host-guest binding event has coupled with the localized surface plasmon resonance (LSPR) arising from gold nanodisc gratings. The creation of a responsive plasmonic device upon the addition of the guest molecule and the subsequent coupling of the charge-transfer (CT) chromophore to the plasmon has provided good opportunities for applications in molecular sensing and active molecular plasmonics.

Several studies are conducted to explain the synthesis and the various scattering, electronic and ferroelectric properties of the different Nd modified [Bi.sub.4][Ti.sub.3][O.sub.12] nanotube arrays.

The ensemble-averaged measurements of colloidal hotspots enabled by the synthesis of highly uniform dimers and trimers of nanoparticles and the quantification of the relative concentrations of the nanoclusters are described.

A combination of the Raman scattering and infrared transmittance techniques is employed to analyze the various optical-active phonons present in the [A.sub.3][Fe.sub.2]B?[O.sub.9] (A = Ca, Sr; B? = Te, W) double perovskites. The different structures and properties of these compounds are also studied.

Surface-Enhanced Raman Scattering (SERS) substrate approach was used to capture the distinct conformational changes of single photoactive yellow protein (PYP) molecules under photoexcitation. The method identified exclusive peak pairs that could elucidate conformational steps in PYP and chemisorption configuration on Ag.

The crystalline Cr(CO)5(CS) and (eta-C6H6)Cr(CO)2(CS) were analyzed by high-pressure infrared spectra. The high-pressure micro-Raman spectra for the pentacarbonyl derivative was likewise investigated. It was observed that metal-CO interactions and the molecular structures of the complexes were affected by changes in pressure. Increased pressure resulted in high dv/dP values.

First- and second-order Raman scattering of zinc blende and wurtzite ZnS are studied. The involvement of LA phonon at X point is considered for reassigning the second-order Raman active modes.

Several analytical studies are conducted to explain the impact of a substrate on the particle assemblies taking place in the surface-enhanced Raman scattering analysis. An appropriate technique for the maximization of the surface electric field is also presented.

A facile technique combining microwave irradiation with mixed-acid-assisted dispersion is efficient for enrichment of semiconducting single-walled carbon nanotubes (s-SWNTs) and also for realizing electronic type-dependent and diameter-dependent separation of SWNTs. Raman and ultraviolet absorption investigations have shown that the chemical structure of carbon nanotubes is restored after thermal annealing.

A method is described for improving femtomole-level trace detection by using large-area surface-enhanced Raman scattering (SERS) substrates. Multiphoton-induced exposure of a commercial photoresist is used for physically limiting the available molecular adsorption sites to only the electromagnetic hot spots on the substrate.

A study of individual tin oxide (Sn[O.sub.2]) nanowire and three-dimensional (3D) branched Sn[O.sub.2] nanowires decorated with Au nanoparticles as the substrates for surface-enhanced Raman scattering (SERS) application is described. The high SERS activity of the 3D branched Sn[O.sub.2] nanowires is attributed to the large number of Au droplets and the formation of lots of 'hot spots' in regions between adjacent Au droplets on tips of the branches.

The effects of connectivity and disorder on the critical current density [J.sub.c] are studied for clarifying the different mechanisms of [J.sub.c](H) enhancement in different magnetic field ranges. Raman scattering measurements have shown a strengthened electron-[E.sub.2g] coupling and weakened disorder with Mg addition.

Core-shell ZnO/ZnMnO nanowires on a-[Al.sub.2][O.sub.3] and GaN (buffer layer)/Si (111) substrates are prepared by pulsed laser deposition using a Au catalyst. Resonant Raman measurements have shown an increase in the multiphoton scattering caused by disorder in ZnO upon doping by Mn.

The studies of surface-enhanced Raman scattering (SERS) spectra of 4-mercaptopyridine molecules excited far from the molecular resonance which are collected from individual electromagnetic hot spots at concentrations close to the single-molecule limit are reported. The measurement of potential-dependent SERS spectra from individual hot spots opens the pathway for a thorough characterization of chemical enhancement, as well to studies of redox phenomena at the single-molecule level.

Resonance Raman intensity analysis is used for calculating the vibronic absorption profile of cyanobacterial phytochrome Cph1. The studies have shown that the shoulder feature is because of vibronic transitions from a single species, thus reflecting a homogeneous ground-state population.

Raman enhancement is calculated in a couple of nanocylinders (one made of silver and other made of silver) and a formulation is presented for enhanced Raman scattering of semiconductor cylinders. The results have shown that the interaction between the silicon cylinder and the silver cylinder is very strong.

A combination of the Raman scattering and x-ray diffraction studies is employed to explain the structures, as well as the magnetic properties of the p-type Mn:Ti[O.sub.2] dilute magnetic semiconductor thin films. The room temperature ferromagnetism is shown to be an intrinsic property of the films.

Phonon modes found in low-frequency Raman scattering from Cd[S.sub.1-x][Se.sub.x] nanocrystals embedded in a borosilicate glass arising from confined acoustic phonons are examined. The appearance of the torsional mode is ascribed to the near-spherical shape of the nanoparticle found from high-resolution transmission electron microscopy and its interaction with the surrounding medium.

Free-electron concentration and mobility of free-standing GaN nanowires (NWs) are determined by line shape analysis of the coupled longitudinal optical phonon-plasmon Raman modes (L+). Asymmetric broadening seen at the lower frequency side of the L+ phonon peak is attributed to the increase in surface optical modes due to the high surface-to-volume ratio of NWs.

Stimuli-responsive surface-enhanced Raman scattering (SERS) nanoparticles are developed by using colloidal gold nanoparticles and a class of thiolated block copolymers consisting of a pH-responsive polymer segment, an amphiphilic polyethylene glycol segment, and a lipoic acid anchoring group. The results have shown that the SERS signals can be switched on and off by molecular conformations in response to pH and neutralized polymethacrylic acid molecules have interacted with amphiphilic polyethylene glycol chains.

A newly developed spatial and tensor deconvolution procedure for the analysis of cumulative Raman frequency shifts recorded in silicon surface zones containing a Blister-type contact stress field is presented. The proposed experimental method could find potential application for in situ assessments of phonon deformation potentials in thin/opaque samples with high refractive index.

The long-term measurements of the blinking (on/off) behavior of the glycerol microdroplet Raman laser is used to demonstrate the dependency of the lasing bursts on the evaporation rate of the microdroplet. The Raman lasing blinking caused by double resonances in the evaporating droplet showed that it could be manipulated by controlling the evaporation rate of droplet.

Attenuation of the x rays and [gamma] rays in the [sub 22]Ti, [sub 41]Nb, [sub 69]Tm, [sub 70]Yb, and [sub 71]Lu elements were measured to understand the x ray energies ([E.sub.in]) in lower vicinity of the K shell ionization threshold ([B.sub.K]) of the element. The observed magnitude of positive alteration at the photon energy in lower vicinity of the ionization threshold is attributed to the K shell resonant Raman scattering (RRS) process and the corresponding cross sections.

Raman scattering of molecules adsorbed on the surface of Ti[O.sub.2] nanoparticles is examined. The wavelength-dependent properties of a hybrid composite has suggested a Raman resonant state and adsorbed molecules not displaying a charge transfer complex has shown weak enhancements due to the dielectric cavity effect.

First-principles calculations are used for predicting a tetragonal phase of B[C.sub.2]N(t-B[C.sub.2]N), which has matched the experiment well because the estimated Vickers hardness and the simulated X-ray diffraction (XRD) and Raman patterns have agreed well with the experimental results. The studies have provided the underlying physics behind the lack of the transverse optical mode in the measured Raman spectrum and also find the electronic structure transition among the polymorph of superhard B[C.sub.2]N compounds.

The evolving nature of carbon nanotube coatings for damage-resistant detectors upon their exposure to incrementally increased laser power levels is explored. Electron microscopy images of the exposed multiwalled carbon nanotubes have shown the formation of intermittent pockets of moundlike structures at high power densities.