Principal Investigator: Alexis Templeton
Director: Eric Ellison
Location: Benson 125B

The Raman Microspectroscopy Laboratory is a core research facility housed in the Department of Geological Sciences for fast, non-destructive characterization and chemical imaging of diverse materials spanning minerals (thin sections & powders), biological samples, fluids, dissolved gases, and much more. Our instrument is especially optimized for fast hyperspectral imaging of complex samples and materials, where a full Raman spectrum is collected at every pixel. This technique, combined with advanced multivariate statistical techniques, facilitates the detection and identification of all Raman-active species present in the area of interest. It is especially powerful for extracting information on the pure end-members of complex mixtures, even when those end-members are always mixed with other components.

As a core facililty we are eager to assist you! We provide access to academic and non-academic researchers with any affiliation for a user fee. Please contact Eric Ellison to set up a meeting to discuss the feasibility of Raman for your project.

Raman spectrometer
Instrument

Our Horiba LabRAM HR Evolution Raman spectrometer.

Mineral mapping example
Application Example

Mineral distributions in partially serpentinized rock from the Samail ophiolite in Oman.

Biological mapping example
Application Example

Vegetative cell (blue) and endospore (red) components in Bacillus.

Instrumentation

The Raman Microspectroscopy Lab owns a Horiba LabRAM HR Evolution Spectrometer. This is a fully confocal, high-resolution 800 mm spectrometer equipped for flexibility across a broad range of applications. Its features include:

  • Two laser sources: 100 mW 532 nm frequency-doubled Nd:YAG and 100 mW 785 nm diode.
  • XY resolution as good as 500 nm, and confocal Z resolution as good as 1 µm.
  • Spectral resolution as good as 0.4 cm-1 (785 nm laser) or 2.5 cm-1 (532 nm laser).
  • Two diffraction gratings for wide spectral range or high spectral resolution.
  • A variety of microscope objective lenses.
  • 10 cm x 10 cm working area stage with motorized control of X, Y, and Z
  • Several options for controlling the polarization of the excitation laser.
  • Reflected and transmitted light sources.
  • X and Y galvo mirrors allowing the laser to be aimed, scanned, and rastered out of the microscope objective without any sample movement.
  • High-speed continuous scanning mode for fast mapping

The Raman lab also has a Nicolet 670 FTIR spectrometer interfaced to a Continuum FTIR microscope for microscale reflection and transmission, as well as bulk transmission FTIR spectroscopy. Additional Raman Lab resources include a Zeiss stereomicroscope, sample preparation area, and a high-performance offline workstation for data processing and statistical analyses.

Applications

Some successful applications of Raman spectroscopy in our lab have included:

  • Silicon carbide, diamond-like carbon, and other thin films
  • Hyperspectral mapping of complex hydrated peridotite rocks
  • Measuring radiation damage in zircon and titanite
  • Quantifying cation substitution in minerals
  • Liquid crystal composition and orientation
  • Locating rare earth minerals in carbonatite
  • Measuring silica polymorphs in chalcedony
  • Mapping distributions of carbonate polymorphs
  • Imaging cells and fluorophores
  • Identifying contaminant inclusions in plastics
  • Imaging interfaces in solid-state batteries
  • Characterizing sulfur and sulfate-rich samples

Publications

Templeton, A.S., and Ellison, E.T. (2020) Formation and loss of metastable brucite: does Fe(II)-bearing brucite support microbial activity in serpentinizing ecosystems? Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 378, 20180423.

Vitkus, A.R., Chin, K., Kirkland, J.I., Milner, A.R.C., Simpson, E.L., and Ellison, E.T. (2020) Unusual fossiliferous concretions from lacustrine deposits in the Lower Jurassic Moenave Formation in St. George, Utah, USA: Implications for ancient fish mass mortalities. PALAIOS, 35, 77–93.

Ozvat, T.M., Peña, M.E., and Zadrozny, J.M. (2019) Influence of ligand encapsulation on cobalt-59 chemical-shift thermometry. Chemical Science 10, 6727-6734.

Mayhew, L.E., Ellison, E.T., Miller, H.M., Kelemen, P.B., and Templeton, A.S. (2018) Iron transformations during low temperature alteration of variably serpentinized rocks from the Samail ophiolite, Oman. Geochimica et Cosmochimica Acta 222, 704–728.

Black, S.R., and Hynek, B.M. (2017) Characterization of terrestrial hydrothermal alteration products with Mars analog instrumentation: Implications for current and future rover investigations. Icarus 307, 235-259.

Hens P., Brow R., Robinson H., Cromar M. and Van Zeghbroeck B. (2017) Epitaxial growth of cubic silicon carbide on silicon using hot filament chemical vapor deposition. Thin Solid Films 635, 48–52.

Miller H. M., Mayhew L. E., Ellison E. T., Kelemen P., Kubo M. and Templeton A. S. (2017) Low temperature hydrogen production during experimental hydration of partially-serpentinized dunite. Geochimica et Cosmochimica Acta 209, 161–183.

Johnson J. E., Flowers R. M., Baird G. B. and Mahan K. H. (2017) “Inverted” zircon and apatite (U–Th)/He dates from the Front Range, Colorado: High-damage zircon as a low-temperature (<50 °C) thermochronometer. Earth and Planetary Science Letters 466, 80–90.

Baughman J. S., Flowers R. M., Metcalf J. R. and Dhansay T. (2017) Influence of radiation damage on titanite He diffusion kinetics. Geochimica et Cosmochimica Acta 205, 50–64.

Miller H. M., Matter J. M., Kelemen P., Ellison E. T., Conrad M. E., Fierer N., Ruchala T., Tominaga M. and Templeton A. S. (2016) Modern water/rock reactions in Oman hyperalkaline peridotite aquifers and implications for microbial habitability. Geochimica et Cosmochimica Acta 179, 217–241.

Zhang L., Smyth J. R., Allaz J., Kawazoe T., Jacobsen S. D. and Jin Z. (2016) Transition metals in the transition zone: Crystal chemistry of minor element substitution in wadsleyite. American Mineralogist 101, 2322–2330.

Cosmidis J. and Templeton A. S. (2016) Self-assembly of biomorphic carbon/sulfur microstructures in sulfidic environments. Nature Communications 7, 12812.

Introductory Resources

Pasteris, J. D. and Beyssac, O., Eds. (2020) Raman Spectroscopy in Earth and Planetary Sciences. Elements 16(2). Mineralogical Society of America.

Dubessy, J., Caumon, M. C., and Rull, F., Eds. (2012). Raman spectroscopy applied to earth sciences and cultural heritage. EMU Notes in Mineralogy 12. The Mineralogical Society of Great Britain and Ireland.

Zoubir, A., Ed. (2012) Raman Imaging: Techniques and Applications. Springer Series in Optical Sciences 168. Springer.