Singlet oxygen luminescence spectra: a comparison of interferometer- and grating-based spectrometers.
The current trend in methodology for determining IR and near-IR absorption spectra is to employ interferometer-based instruments to replace the monochromator-based devices used heretofore. As a dispersion element, the interferometer offers major improvements in spectral resolution (Connes advantage), light throughput (Jacquinot advantage) and data acquisition through multiplexing (Felgett advantage). We have compared signal-to-noise (S/N) ratios of grating-based and interferometer-based instruments for making spectral determinations of near-IR luminescence. Our results show that under identical excitation and detector conditions the interferometer instrument easily outperforms the grating, giving a 10-fold improvement in S/N at high signal amplitude (A488nm = 0.97) and a 20-fold improvement when the signal amplitude is low (A488nm = 0.06). Although some spectral resolution is sacrificed when scan times on the Fourier transform (FT)IR are significantly shortened, the S/N ratio was found only to decrease by a factor of 2 for a 10-fold decrease in scan time. This adds to the advantages of the FTIR technique because the S/N will thus improve for the same total acquisition time.
Wessels
J M
JM
Center for Photochemical Sciences, Bowling Green State University, OH 43403, USA.
Charlesworth
P
P
Rodgers
M A
MA
D005069:Evaluation Studies as Topic; D007368:Interferometry / Q000379:methods*; D049449:Luminescence; D010100:Oxygen / Q000737:chemistry*; D010777:Photochemistry; D026082:Singlet Oxygen; D013055:Spectrophotometry, Infrared / Q000379:methods*
D026082:Singlet Oxygen; D010100:Oxygen