The use of a Chevron filter for the rejection of light at the 1064-nm excitation wavelength permits the simultaneous detection of Stokes and anti-Stokes Raman lines (doubled multiplexing). This enhances spectrometry and photometric accuracy and permits a measurement of the true vibrational temperature of the sample. Down to Raman shifts as low as 40 cm−1, near-IR Raman spectra recorded on an optimized Nicolet SXR 60 instrument are distinctly superior to previously reported spectra of similar samples recorded on FT or, more slowly, on dispersive instruments.
