Gas-phase databases for quantitative infrared spectroscopy.
The National Institute of Standards and Technology (NIST) and the Pacific Northwest National Laboratory (PNNL) are each creating quantitative databases containing the vapor-phase infrared spectra of pure chemicals. The digital databases have been created with both laboratory and remote-sensing applications in mind. A spectral resolution of approximate, equals 0.1 cm(-1) was selected to avoid degrading sharp spectral features, while also realizing that atmospheric broadening typically limits line widths to 0.1 cm(-1). Calculated positional (wave- number, cm(-1)) uncertainty is </=0.005 cm(-1), while the 1sigma statistical uncertainty in absorbance values is <2% for most compounds. The latter was achieved by measuring multiple (typically >/=9) path length-concentration burdens and fitting a weighted Beer's law plot to each wavenumber channel. The two databases include different classes of compounds and were compared using 12 samples. Though these 12 samples span a range of polarities, absorption strengths, and vapor pressures, the data agree to within experimental uncertainties with only one exception.
Sharpe
Steven W
SW
Pacific Northwest National Laboratory, P. O. Box 999, Richland, Washington 99352, USA.
Johnson
Timothy J
TJ
Sams
Robert L
RL
Chu
Pamela M
PM
Rhoderick
George C
GC
Johnson
Patricia A
PA
D002138:Calibration / Q000592:standards; D016208:Databases, Factual; D005740:Gases / Q000032:analysis* / Q000737:chemistry / Q000592:standards*; D044367:Phase Transition; D012015:Reference Standards; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017550:Spectroscopy, Fourier Transform Infrared / Q000295:instrumentation / Q000379:methods* / Q000592:standards*; D014481:United States
D005740:Gases