Raman Spectroscopy

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The presence of electronic transitions in the visible part of the spectrum can provide enormous enhancement of Raman signals.

A modern portable Raman instrument equipped with a 1064-nm laser is compared to one using a 785-nm laser for the identification of counterfeit pharmaceuticals.

Results are reported from studies using volume holographic grating filter technology with both visible and NIR excitation wavelengths to analyze multiple forms of the polymorphic active pharmaceutical ingredient carbamazepine.

This article re-explains and demystifies some definitions and opinions concerning Raman spectroscopy from two distinct sides: academic and industrial.

The feasibility of identifying different types of bacterial growth media using a handheld Raman instrument with a proprietary baseline correction algorithm is investigated.

With improvements in instrumentation, Raman spectroscopy continues to expand its range of applications to diverse areas of materials analysis and research.

Here, real spectra illustrate how to be your own critic when evaluating band-fitted spectra.

Micro-Raman spectroscopy has been used to depth-profile a waveguide produced by an ion-exchange reaction in a single crystal of a ferroelectric metal oxide, and to reveal the changes in chemical bonding and atomic structure that occur in this process.

This tutorial demonstrates that Raman is well-suited to tackle two challenges faced by industry: complex mixtures and isomers.

SERS of bacterial cells can be a useful technique for clinical diagnostics, as illustrated by the analysis of a human urine sample spiked with urinary tract infection bacteria.

SERDS analysis can be easily and successfully carried out using two high-power laser diodes with a fixed-wavelength separation in the presence of high fluorescence.

The orientation of a crystal can be determined from the phase shift of the experimental P/O micro-Raman diagram relative to that calculated for a particular crystal face.

Raman spectroscopy is a non-destructive technique that requires little or no sample preparation. Participants in this forum are Tom Tague, of Bruker Optics, and Robert Chimenti, of B&W Tek.

Polarization/orientation micro-Raman spectroscopy promises to be an important analytical tool to complement micro-X-ray diffraction.

A quick and accurate method for detecting the antifungal agent crystal violet in aquaculture.

The Coblentz Society and the Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) recently named Professor Duncan Graham of the University of Strathclyde (Glasgow, Scotland) as the recipient of the Coblentz Society?s 2012 Craver Award.

Raman has a unique capability to characterize nanoscale materials that are between crystalline and amorphous.

Confocal Raman microscopy can identify particles in the 5–50 ?m range and can bridge the gap between micro-FT-IR and SEM-EDS analyses.

In the three decades since its discovery, surface-enhanced Raman scattering (SERS) has been used in numerous applications to increase signal intensity in Raman scattering experiments. The current study provides insight into the more practical aspects of enhanced Raman sampling for laboratory users. We describe how the signal enhancement from a surface-enhanced resonant Raman scattering (SERRS) process improves the ability to discriminate between ink samples using principal component clustering.

Temperature measurements can be made using spectral features such as the position, linewidth, and intensity of the Raman signal associated with specific optical phonon modes. Each of these spectral characteristics offers particular advantages, depending on the type of device and operational considerations.

A critical review focused on the Raman spectroscopy of carbonaceous materials and of polymer-based nanocomposites that contain carbonaceous (nano) materials as fillers

How can you navigate the maze of choices for detecting molecular vibrations with mid-infrared (IR), near IR (NIR), and visible (Raman)? Understanding what is being measured, how it is measured, and the advantages and disadvantages of each technique, will help.

In the three decades since its discovery, surface-enhanced Raman scattering (SERS) has been used in numerous applications to increase signal intensity in Raman scattering experiments. The current study provides insight into the more practical aspects of enhanced Raman sampling for laboratory users.

A few key steps will protect your samples and help ensure accurate results.

Developments in lasers, detectors, low-cost instruments, and fiber-optic probes have greatly expanded the lubrication systems being studied by Raman spectroscopy.

Surface plasmon resonance, charge-transfer resonance, and their combination determine the enhancement of surface-enhanced Raman scattering signals, and the varying intensities of the signal at different pH levels may result from the change in contributions of the combined system.

A portable Raman analyzer with laser excitation at 1550 nm provides "eye-safe" explosives detection.

A compact standoff Raman system can be used to detect hazardous chemicals and chemicals used in homemade explosives synthesis.

Spatially offset and transmission Raman spectroscopy enable chemical characterization of diffusely scattering samples at depths not accessible by conventional Raman methods.