RENISHAW MK III Raman Spectrometer

A RENISHAW MK III Raman spectrometer was used, utilizing a 30mW argon laser emitting green light at a wavelength of 514.53 nm as an excitation source. The light was transported through a 50µm optic fiber cable to the probe and was focused on the sample via a 20X objective lens.

Back-scattered light was filtered using a 2400 grooves/mm grating. The spectrometer was calibrated using the emission lines from neon, assuring an accuracy of 0.3 cm^-1, while the spectral resolution was 4.5 cm^-1. Raman spectra were analyzed using GRAMS/32^® software from Galactic Industries Corporation.

The cell used was custom-designed and fabricated by Sam Colgate. The cell is a high-pressure, variable temperature 1 cm³ sapphire windowed cell, with a pressure range over 70 MPa. The viewing area is 200 mm². The cell is jacketed, and the temperature is controlled by circulating coolant water.