Raman Spectroscopy

Click here to view the complete Wavelength newsletter from December 17, 2013.

In this interview with Spectroscopy, renowned planetary spectroscopist Alian Wang of Washington University in St. Louis discusses the development of the Mars microbeam Raman spectrometer (MMRS), proposed to be part of science payload for the NASA-funded mission, Mars 2020. Wang discusses the challenges involved in making the instrument robust enough for operation in space, and highlights how data collected from over 18 years has advanced our understanding of the history of Mars.

In this study, regression and classification chemometrical algorithms were combined to achieve effective discrimination of pure body fluids from their binary mixtures.

A summary of the efforts to study microorganism biofilms using surface-enhanced Raman scattering, a powerful technique for in situ analysis of biological molecules and biomolecular organizations

The physics that determine how gratings and spectrographs work are summarized in simple terms for new users of Raman equipment.

Click here to view the complete Wavelength newsletter from September 10, 2013.

What exactly is a "Raman image" and how is it rendered? The authors explain those points, and demonstrate the use of Raman imaging for the characterization of thin-film and ion-implanted silicon structures. High spectral resolution makes it possible to resolve or contrast the substrate silicon and polysilicon film in Raman images and thus aids in the chemical or physical differentiation of spectrally similar materials.

Click here to view the complete Wavelength newsletter from June 19, 2013.

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.